diff --git a/.gitignore b/.gitignore
index af96791fc..3d77281fb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
+llvm-mos-sdk.code-workspace
 .vscode
 build
diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt
index edf4a87a6..8d391f85c 100644
--- a/examples/CMakeLists.txt
+++ b/examples/CMakeLists.txt
@@ -36,3 +36,6 @@ endif()
 if(PLATFORM MATCHES rpc8e)
   add_subdirectory(rpc8e)
 endif()
+if(PLATFORM MATCHES ^cx16)
+  add_subdirectory(cx16)
+endif()
diff --git a/examples/cx16/CMakeLists.txt b/examples/cx16/CMakeLists.txt
new file mode 100644
index 000000000..00ffaf98f
--- /dev/null
+++ b/examples/cx16/CMakeLists.txt
@@ -0,0 +1,11 @@
+add_executable(k_console_test.prg k_console_test.c)
+install_example(k_console_test.prg)
+
+add_executable(k_datetime_test.prg k_datetime_test.c)
+install_example(k_datetime_test.prg)
+
+add_executable(k_graph_test.prg k_graph_test.c)
+install_example(k_graph_test.prg)
+
+add_executable(k_graph_line_test.prg k_graph_line_test.c)
+install_example(k_graph_line_test.prg)
diff --git a/examples/cx16/k_console_test.c b/examples/cx16/k_console_test.c
new file mode 100644
index 000000000..01ddb5446
--- /dev/null
+++ b/examples/cx16/k_console_test.c
@@ -0,0 +1,54 @@
+// llvm-mos-sdk cx16 kernel test
+//
+// vim: set et ts=4 sw=4
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include <cbm.h>
+#include <cx16.h>
+
+unsigned char face[64] = {
+    1, 1, 1, 1, 1, 1, 1, 1,
+    1, 1, 0, 0, 0, 0, 1, 1,
+    1, 0, 1, 0, 0, 1, 0, 1,
+    1, 0, 0, 0, 0, 0, 0, 1,
+    1, 0, 1, 0, 0, 1, 0, 1,
+    1, 0, 0, 1, 1, 0, 0, 1,
+    1, 1, 0, 0, 0, 0, 1, 1,
+    1, 1, 1, 1, 1, 1, 1, 1
+};
+
+void wait_key(void)
+{
+    while (cbm_k_getin() == 0)
+        ;
+}
+
+void console_puts(const char *str, unsigned char wordwrap)
+{
+    uint8_t c = 0;
+    while ((c = *str++) != 0)
+    {
+        cx16_k_console_put_char(c, wordwrap);
+    }
+}
+
+int main(void)
+{
+    cx16_k_screen_mode_set(128);
+    cx16_k_graph_set_colors(1, 0, 0);
+    cx16_k_console_init(0, 0, 0, 0);
+    console_puts("\x92Hello Commander X16!", 0);
+
+    wait_key();
+
+    // BUG: I don't understand why this clears/scrolls screen...
+    cx16_k_console_put_image(face, 8, 8);
+
+    wait_key();
+
+    cx16_k_screen_mode_set(0);
+    printf("DONE.\n");
+}
diff --git a/examples/cx16/k_datetime_test.c b/examples/cx16/k_datetime_test.c
new file mode 100644
index 000000000..bbe0a94b0
--- /dev/null
+++ b/examples/cx16/k_datetime_test.c
@@ -0,0 +1,70 @@
+// llvm-mos-sdk cx16 kernel test
+//
+// vim: set et ts=4 sw=4
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include <cbm.h>
+#include <cx16.h>
+
+static void hexdump(const void *ptr, size_t bytes)
+{
+    uint8_t *p = (uint8_t *)ptr;
+    for (size_t i = 0; i < bytes; i++)
+    {
+        if ((i & 0xf) == 0)
+        {
+            if (i)
+            {
+                printf("\n");
+            }
+            printf("%04x: ", i);
+        }
+        else
+        {
+            printf(", ");
+        }
+        printf("%02x", p[i]);
+    }
+    printf("\n");
+}
+
+int main(void)
+{
+    static cx16_date_time_t tm;
+
+    putchar(15); // ISO mode
+    printf("llvm-mos-sdk CX16 Kernal Test\n\n");
+
+    printf("\ncx16_k_clock_get_date_time(&tm);\n");
+    cx16_k_clock_get_date_time(&tm);
+
+    printf("Result: year=%d, mon=%d, day=%d, hour=%d, min=%d, sec=%d, jif=%d\n",
+           1900 + tm.year,
+           tm.mon,
+           tm.day,
+           tm.hour,
+           tm.min,
+           tm.sec,
+           tm.jif);
+    hexdump(&tm, sizeof(tm));
+
+    printf("\ncx16_k_clock_set_date_time(2023-1900, 4, 5, 10, 12, 13, 42);\n");
+    cx16_k_clock_set_date_time(2023 - 1900, 4, 5, 10, 12, 13, 42);
+
+    cx16_k_clock_get_date_time(&tm);
+
+    printf("Result: year=%d, mon=%d, day=%d, hour=%d, min=%d, sec=%d, jif=%d\n",
+           1900 + tm.year,
+           tm.mon,
+           tm.day,
+           tm.hour,
+           tm.min,
+           tm.sec,
+           tm.jif);
+    hexdump(&tm, sizeof(tm));
+
+    printf("Done\n"); // finished
+}
diff --git a/examples/cx16/k_graph_line_test.c b/examples/cx16/k_graph_line_test.c
new file mode 100644
index 000000000..e625ecce1
--- /dev/null
+++ b/examples/cx16/k_graph_line_test.c
@@ -0,0 +1,37 @@
+// llvm-mos-sdk cx16 kernel test
+//
+// vim: set et ts=4 sw=4
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include <cbm.h>
+#include <cx16.h>
+
+int main(void)
+{
+    int16_t x, y;
+    uint8_t c;
+
+    cx16_k_screen_mode_set(128);        // 320x240x8-bpp
+    cx16_k_graph_init(NULL);            // initialize kernal graph with defaults
+    c = 0;                              // initialize color
+
+    // draw line pattern
+    for (y = 0; y < 240; y += 3)
+    {
+        cx16_k_graph_set_colors(c++, 0, 0);
+        cx16_k_graph_draw_line(0, y, 319, 239 - y);
+    }
+
+    for (x = 0; x < 320; x += 3)
+    {
+        cx16_k_graph_set_colors(c++, 0, 0);
+        cx16_k_graph_draw_line(x, 0, 319 - x, y);
+    }
+
+    while (cbm_k_getin() == 0)        // wait for a keypress
+        ;
+
+    cx16_k_screen_mode_set(0);        // reset screen mode to 80x30
+}
diff --git a/examples/cx16/k_graph_test.c b/examples/cx16/k_graph_test.c
new file mode 100644
index 000000000..24fab6c29
--- /dev/null
+++ b/examples/cx16/k_graph_test.c
@@ -0,0 +1,129 @@
+// llvm-mos-sdk cx16 kernel test
+//
+// vim: set et ts=4 sw=4
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include <cbm.h>
+#include <cx16.h>
+
+unsigned char face[64] = {1, 1, 1, 1, 1, 1, 1, 1,
+                          1, 1, 0, 0, 0, 0, 1, 1,
+                          1, 0, 5, 0, 0, 5, 0, 1,
+                          1, 0, 0, 0, 0, 0, 0, 1,
+                          1, 0, 1, 0, 0, 1, 0, 1,
+                          1, 0, 0, 1, 1, 0, 0, 1,
+                          1, 1, 0, 0, 0, 0, 1, 1,
+                          1, 1, 1, 1, 1, 1, 1, 1
+                         };
+
+void wait_key(void)
+{
+    while (cbm_k_getin() == 0)
+        ;
+}
+
+void graph_put_string(unsigned int x, unsigned int y, const char *str)
+{
+    graph_pos_t pos;
+    pos.x = x;
+    pos.y = y;
+    uint8_t c = 0;
+    while ((c = *str++) != 0)
+    {
+        cx16_k_graph_put_char(&pos, c);
+    }
+}
+
+int main(void)
+{
+    uint8_t scolor = 1;             // stroke color
+    int16_t xpos = 160, ypos = 120; // initial face position
+    int8_t xd = 1;                  // initial face direction
+
+    // set 320x240x8-bpp
+    cx16_k_screen_mode_set(128);
+
+    // init default graphics driver
+    cx16_k_graph_init(0);
+
+    // default font
+    cx16_k_graph_set_font(0);
+
+    // draw outline box
+    cx16_k_graph_set_colors(4, 0, 0);
+    cx16_k_graph_draw_line(10, 10, 320 - 10, 10);
+    cx16_k_graph_draw_line(320 - 10, 10, 320 - 10, 240 - 10);
+    cx16_k_graph_draw_line(320 - 10, 240 - 10, 10, 240 - 10);
+    cx16_k_graph_draw_line(10, 240 - 10, 10, 10);
+
+    // welcome message
+    cx16_k_graph_set_colors(0, 0, 0);
+    graph_put_string(75, 20, "Hello Commander X16 and llvm-mos!\n\n              Basic cx16_k_graph* wrapper test...");
+
+    // window clipping test
+    cx16_k_graph_set_window(0, 0, 320 / 2, 240);
+    cx16_k_graph_set_colors(4, 0, 0);
+    graph_put_string(50, 60, "This text is using clipping to draw in two colors.");
+    cx16_k_graph_set_window(320 / 2, 0, 320 / 2, 240);
+    cx16_k_graph_set_colors(5, 0, 0);
+    graph_put_string(50, 60, "This text is using clipping to draw in two colors.");
+
+    // full screen window
+    cx16_k_graph_set_window(0, 0, 0, 0);
+
+    // draw outline rectangle
+    cx16_k_graph_set_colors(6, 0, 0);
+    cx16_k_graph_draw_rect(50, 50, 42, 14, 0, 0);
+    // move (copy) rectangle
+    cx16_k_graph_move_rect(50, 50, 65, 65, 42, 15);
+
+    // label moved rectangle
+    cx16_k_graph_set_colors(0, 0, 0);
+    graph_put_string(110, 75, "<- rectangle moved here");
+
+    // stop message
+    graph_put_string(110, 240 - 20, "Press a key to stop");
+
+    // until a key is pressed, bounce face and rectangle
+    while (cbm_k_getin() == 0)
+    {
+        // draw 8x8 "face" image
+        cx16_k_graph_draw_image(xpos, ypos, face, 8, 8);
+
+        // update x position
+        xpos += xd;
+
+        // if near edges, reverse direction
+        if (xpos < 64 || xpos > 320 - 64)
+        {
+            xd = -xd;
+        }
+
+        // draw filled rectangle offset from face using incrementing color
+        scolor += 1;
+        cx16_k_graph_set_colors(scolor, scolor + 1, 0);
+        cx16_k_graph_draw_rect(xpos - 12, ypos + 20, 8, 16, 0, 1);
+
+        waitvsync();
+    }
+
+    // erase old message
+    cx16_k_graph_set_colors(1, 1, 1);
+    cx16_k_graph_draw_rect(20, 240 - 20 - 10, 280, 20, 0, 1);
+
+    // exit message
+    cx16_k_graph_set_colors(0, 0, 0);
+    graph_put_string(110, 240 - 20, "Press a key to exit");
+
+    // wait for final key press
+    wait_key();
+
+    // restore 80x60 text mode
+    cx16_k_screen_mode_set(0);
+
+    // done message
+    printf("DONE.\n");
+}
diff --git a/mos-platform/atari8-common/atari.h b/mos-platform/atari8-common/atari.h
index 1844e481f..b60fcf5b1 100644
--- a/mos-platform/atari8-common/atari.h
+++ b/mos-platform/atari8-common/atari.h
@@ -3,7 +3,7 @@
 // See https://github.com/llvm-mos/llvm-mos-sdk/blob/main/LICENSE for license
 // information.
 
-// Originally from cc65. Modififed from original version.
+// Originally from cc65. Modified from original version.
 
 /*****************************************************************************/
 /*                                                                           */
diff --git a/mos-platform/c64/c64.h b/mos-platform/c64/c64.h
index 6c66d0c79..6a77719e6 100644
--- a/mos-platform/c64/c64.h
+++ b/mos-platform/c64/c64.h
@@ -3,7 +3,7 @@
 // See https://github.com/llvm-mos/llvm-mos-sdk/blob/main/LICENSE for license
 // information.
 
-// Originally from cc65. Modififed from original version.
+// Originally from cc65. Modified from original version.
 
 /*****************************************************************************/
 /*                                                                           */
diff --git a/mos-platform/commodore/CMakeLists.txt b/mos-platform/commodore/CMakeLists.txt
index 7835601aa..0ed574f03 100644
--- a/mos-platform/commodore/CMakeLists.txt
+++ b/mos-platform/commodore/CMakeLists.txt
@@ -30,7 +30,8 @@ add_platform_library(commodore-c
   cbm_k_chkin.s
   cbm_k_chrin.c
   cbm_k_chrout.c
-  cbm_k_ciout.c 
+  cbm_k_cint.c
+  cbm_k_ciout.c
   cbm_k_ckout.s
   cbm_k_clall.c
   cbm_k_close.c
diff --git a/mos-platform/commodore/cbm.h b/mos-platform/commodore/cbm.h
index 6fb0b58b9..bf624223b 100644
--- a/mos-platform/commodore/cbm.h
+++ b/mos-platform/commodore/cbm.h
@@ -3,7 +3,7 @@
 // See https://github.com/llvm-mos/llvm-mos-sdk/blob/main/LICENSE for license
 // information.
 
-// Originally from cc65. Modififed from original version.
+// Originally from cc65. Modified from original version.
 
 /*****************************************************************************/
 /*                                                                           */
@@ -206,6 +206,7 @@ void cbm_k_bsout (unsigned char C);
 unsigned char cbm_k_chkin (unsigned char FN);
 unsigned char cbm_k_chrin (void);
 void cbm_k_chrout (unsigned char C);
+void cbm_k_cint (void);
 void cbm_k_ciout (unsigned char C);
 unsigned char cbm_k_ckout (unsigned char FN);
 void cbm_k_clall (void);
@@ -214,10 +215,10 @@ void cbm_k_clrch (void);
 unsigned char cbm_k_getin (void);
 unsigned cbm_k_iobase (void);
 void cbm_k_listen (unsigned char dev);
-unsigned int cbm_k_load(unsigned char flag, unsigned addr);
+void *cbm_k_load(unsigned char flag, void *startaddr);
 unsigned char cbm_k_open (void);
 unsigned char cbm_k_readst (void);
-unsigned char cbm_k_save(unsigned int start, unsigned int end);
+unsigned char cbm_k_save(void *startaddr, void *endaddr_plusone);
 void cbm_k_scnkey (void);
 void cbm_k_second (unsigned char addr);
 void cbm_k_setlfs (unsigned char LFN, unsigned char DEV,
diff --git a/mos-platform/commodore/cbm_k_cint.c b/mos-platform/commodore/cbm_k_cint.c
new file mode 100644
index 000000000..2b0e8f7e5
--- /dev/null
+++ b/mos-platform/commodore/cbm_k_cint.c
@@ -0,0 +1,5 @@
+extern void __CINT(void);
+
+void cbm_k_cint(void) {
+	__CINT();
+}
diff --git a/mos-platform/commodore/cbm_k_load.s b/mos-platform/commodore/cbm_k_load.s
index 610235936..a3bd30e23 100644
--- a/mos-platform/commodore/cbm_k_load.s
+++ b/mos-platform/commodore/cbm_k_load.s
@@ -3,18 +3,19 @@
 .text
 
 ;
-; unsigned int cbm_k_load(unsigned char flag, unsigned addr);
+; void *cbm_k_load(unsigned char verifyflag, void *startaddr);	// if result address < 256, likely an error code
+;                                a           rc2/3
 ;
 .global cbm_k_load
 cbm_k_load:
-	ldy __rc2
+	ldx __rc2
+	ldy __rc2+1
 	jsr __LOAD
 	bcc noerror
 	; error code in a ;
 	ldx #0
 	rts
 noerror:
-	txa
-	sty __rc2
-	ldx __rc2
+	stx __rc2	; store end+1 low
+	sty __rc2+1	; store end+1 high
 	rts
diff --git a/mos-platform/commodore/cbm_k_save.s b/mos-platform/commodore/cbm_k_save.s
index cd9851452..69f588f4f 100644
--- a/mos-platform/commodore/cbm_k_save.s
+++ b/mos-platform/commodore/cbm_k_save.s
@@ -2,15 +2,14 @@
 .text
 
 ;
-; unsigned char cbm_k_save(unsigned int start, unsigned int end);
+; unsigned char cbm_k_save(void *startaddr, void *endaddr_plusone);
+;                                rc2/3            rc4/5
 ;
 .global cbm_k_save
 cbm_k_save:
-	sta __rc4
-	stx __rc5
-	ldx __rc2
-	ldy __rc3
-	lda #__rc4
+	ldx __rc4
+	ldy __rc5
+	lda #__rc2
 	jsr __SAVE
 	bcs someerror
 	lda #0
diff --git a/mos-platform/commodore/cbm_kernal.inc b/mos-platform/commodore/cbm_kernal.inc
index 9b88134ef..e8776322a 100644
--- a/mos-platform/commodore/cbm_kernal.inc
+++ b/mos-platform/commodore/cbm_kernal.inc
@@ -14,13 +14,15 @@
 
 #ifdef __CX16__
   ; CX16 extended jump table
+  SAVEHL                        = $FEBA
   KBDBUF_PEEK                   = $FEBD
   KBDBUF_GET_MODIFIERS          = $FEC0
   KBDBUF_PUT                    = $FEC3
   I2C_READ_BYTE                 = $FEC6
   I2C_WRITE_BYTE                = $FEC9
-  CX_MONITOR                    = $FECC
+  MONITOR                       = $FECC
   ENTROPY_GET                   = $FECF
+  KEYMAP                        = $FED2
   CONSOLE_SET_PAGE_MSG          = $FED5
   CONSOLE_PUT_IMAGE             = $FED8
   CONSOLE_INIT                  = $FEDB
@@ -58,8 +60,8 @@
   GRAPH_SET_FONT                = $FF3B
   GRAPH_GET_CHAR_SIZE           = $FF3E
   GRAPH_PUT_CHAR                = $FF41
-  MULTI_ACPTR                   = $FF44
-  RESTORE_BASIC                 = $FF47
+  MACPTR                        = $FF44
+  ENTER_BASIC                   = $FF47
   CLOCK_SET_DATE_TIME           = $FF4D
   CLOCK_GET_DATE_TIME           = $FF50
   JOYSTICK_SCAN                 = $FF53
@@ -68,6 +70,7 @@
   SCREEN_SET_CHARSET            = $FF62
   MOUSE_CONFIG                  = $FF68
   MOUSE_GET                     = $FF6B
+  MOUSE_SCAN                    = $FF71
 #endif
 
 #ifdef __C128__
diff --git a/mos-platform/cx16/CMakeLists.txt b/mos-platform/cx16/CMakeLists.txt
index fbd1962f3..ecd9adcad 100644
--- a/mos-platform/cx16/CMakeLists.txt
+++ b/mos-platform/cx16/CMakeLists.txt
@@ -7,8 +7,81 @@ endif()
 install(FILES _6522.h cx16.h TYPE INCLUDE)
 install(FILES imag-regs.ld link.ld TYPE LIB)
 
+install(FILES cx16.inc DESTINATION ${ASMINCDIR})
+
 add_platform_object_file(cx16-basic-header basic-header.o basic-header.S)
 
-add_platform_library(cx16-c kernal.S)
-target_include_directories(cx16-c BEFORE PUBLIC .)
+add_platform_library(cx16-c
+ cx16_k_clock_get_date_time.s
+ cx16_k_clock_set_date_time.s
+ cx16_k_console_get_char.s
+ cx16_k_console_init.s
+ cx16_k_console_put_char.s
+ cx16_k_console_put_image.s
+ cx16_k_console_set_paging_message.s
+ cx16_k_enter_basic.s
+ cx16_k_entropy_get.s
+ cx16_k_fb_cursor_next_line.s
+ cx16_k_fb_cursor_position.s
+ cx16_k_fb_fill_pixels.s
+ cx16_k_fb_filter_pixels.s
+ cx16_k_fb_get_info.s
+ cx16_k_fb_get_pixel.s
+ cx16_k_fb_get_pixels.s
+ cx16_k_fb_init.s
+ cx16_k_fb_move_pixels.s
+ cx16_k_fb_set_8_pixels.s
+ cx16_k_fb_set_8_pixels_opaque.s
+ cx16_k_fb_set_palette.s
+ cx16_k_graph_clear.s
+ cx16_k_graph_draw_image.s
+ cx16_k_graph_draw_line.s
+ cx16_k_graph_draw_oval.s
+ cx16_k_graph_draw_rect.s
+ cx16_k_graph_get_char_size.s
+ cx16_k_graph_init.s
+ cx16_k_graph_move_rect.s
+ cx16_k_graph_put_char.s
+ cx16_k_graph_set_colors.s
+ cx16_k_graph_set_font.s
+ cx16_k_graph_set_window.s
+ cx16_k_i2c_read_byte.s
+ cx16_k_i2c_write_byte.s
+ cx16_k_joystick_get.s
+ cx16_k_joystick_scan.s
+ cx16_k_kbdbuf_get_modifiers.s
+ cx16_k_kbdbuf_peek.s
+ cx16_k_kbdbuf_put.s
+ cx16_k_keymap_get_id.s
+ cx16_k_keymap_set.s
+ cx16_k_macptr.s
+ cx16_k_memory_copy.s
+ cx16_k_memory_crc.s
+ cx16_k_memory_decompress.s
+ cx16_k_memory_fill.s
+ cx16_k_monitor.s
+ cx16_k_mouse_config.s
+ cx16_k_mouse_get.s
+ cx16_k_mouse_scan.s
+ cx16_k_savehl.s
+ cx16_k_screen_mode_get.s
+ cx16_k_screen_mode_set.s
+ cx16_k_screen_set_charset.s
+ cx16_k_sprite_set_image.s
+ cx16_k_sprite_set_position.s
+ get_numbanks.s
+ get_ostype.s
+ get_tv.s
+ set_tv.s
+ vera_layer_enable.s
+ vera_sprites_enable.s
+ videomode.s
+ vpeek.s
+ vpoke.s
+ waitvsync.s
+ kernal.S
+)
 
+target_include_directories(cx16-c BEFORE PUBLIC .)
+target_compile_options(cx16-c PUBLIC -mcpu=mosw65c02)
+target_link_libraries(cx16-c PRIVATE common-asminc cx16)
diff --git a/mos-platform/cx16/NOTES.md b/mos-platform/cx16/NOTES.md
new file mode 100644
index 000000000..84ac3b72b
--- /dev/null
+++ b/mos-platform/cx16/NOTES.md
@@ -0,0 +1,5 @@
+# Commander X16 llvm-mos-sdk notes
+
+llvm-mos-sdk CX16 kernel stubs - Xark 2023 - [https://github.com/XarkLabs](https://github.com/XarkLabs)
+
+TODO: Do fb_* function wrappers make sense?  Should these be calling via RAM vectors (or additional ifb_* versions)?
diff --git a/mos-platform/cx16/_6522.h b/mos-platform/cx16/_6522.h
index fa03eccab..33000ed4d 100644
--- a/mos-platform/cx16/_6522.h
+++ b/mos-platform/cx16/_6522.h
@@ -3,7 +3,7 @@
 // See https://github.com/llvm-mos/llvm-mos-sdk/blob/main/LICENSE for license
 // information.
 //
-// Originally from cc65. Modififed from original version.
+// Originally from cc65. Modified from original version.
 
 /*****************************************************************************/
 /*                                                                           */
diff --git a/mos-platform/cx16/basic-header.S b/mos-platform/cx16/basic-header.S
index 0bfea77aa..52aeb41c6 100644
--- a/mos-platform/cx16/basic-header.S
+++ b/mos-platform/cx16/basic-header.S
@@ -2,11 +2,11 @@
 ; follows the header if it's at the beginning of BASIC memory ($0801).
 
 .section .basic_header,"aR",@progbits
-	.short next_line	; address of next BASIC line
-	.short 7773 		; line number: l33t for LLVM, a hint that this program was
-						; compiled with LLVM
+	.short next_line		; address of next BASIC line
+	.short 7773			; line number: l33t for LLVM, a hint that this program was
+					; compiled with LLVM
 	.byte 0x9e			; SYS keyword BASIC token
 	.mos_addr_asciz _start, 4	; the location of the _start symbol, in 4 decimal
-						; ASCII digits
+					; ASCII digits
 next_line:
-	.short 0   			; end of basic program
+	.short 0  			; end of basic program
diff --git a/mos-platform/cx16/cx16.h b/mos-platform/cx16/cx16.h
index 5f45a31e1..a9f7046b3 100644
--- a/mos-platform/cx16/cx16.h
+++ b/mos-platform/cx16/cx16.h
@@ -3,7 +3,7 @@
 // See https://github.com/llvm-mos/llvm-mos-sdk/blob/main/LICENSE for license
 // information.
 //
-// Originally from cc65. Modififed from original version.
+// Originally from cc65. Modified from original version.
 
 /*****************************************************************************/
 /*                                                                           */
@@ -141,6 +141,7 @@
 
 /* get_tv() return codes
 ** set_tv() argument codes
+** NOTE: llvm-mos-sdk added newer 240P modes
 */
 enum {
     TV_NONE                     = 0x00,
@@ -150,7 +151,15 @@ enum {
     TV_NONE2,
     TV_VGA2,
     TV_NTSC_MONO,
-    TV_RGB2
+    TV_RGB2,
+    TV_NONE_240P,
+    TV_VGA_240P,
+    TV_NTSC_COLOR_240P,
+    TV_RGB_240P,
+    TV_NONE2_240P,
+    TV_VGA2_240P,
+    TV_NTSC_MONO_240P,
+    TV_RGB2_240P
 };
 
 /* Video modes for videomode() */
@@ -296,5 +305,164 @@ struct __emul {
 /* An array window into the half Mebibyte or two Mebibytes of banked RAM */
 #define BANK_RAM        ((volatile unsigned char *)0xA000)
 
-/* End of cX16.h */
-#endif
+/*****************************************************************************/
+/*                          CX16 kernal functions                            */
+/*****************************************************************************/
+
+/* Kernel function structure type definitions */
+typedef struct
+{
+    unsigned char year, mon, day, hour, min, sec, jif;
+} cx16_date_time_t; /* cx16_k_clock_get_date_time() */
+
+typedef struct
+{
+    unsigned int width, height;
+    unsigned char depth;
+} cx16_fb_info_t; /* cx16_k_fb_get_info_depth() */
+
+typedef struct
+{
+    void *fb_init;
+    void *fb_get_info;
+    void *fb_set_palette;
+    void *fb_cursor_position;
+    void *fb_cursor_next_line;
+    void *fb_get_pixel;
+    void *fb_get_pixels;
+    void *fb_set_pixel;
+    void *fb_set_pixels;
+    void *fb_set_8_pixels;
+    void *fb_set_8_pixels_opaque;
+    void *fb_fill_pixels;
+    void *fb_filter_pixels;
+    void *fb_move_pixels;
+} graph_fb_functions_t; /* cx16_k_graph_init() */
+
+typedef struct
+{
+    int x, y;
+} graph_pos_t;  /* fb_graph_put_char() */
+
+typedef struct
+{
+    int x, y;
+} mouse_pos_t; /* cx16_k_mouse_get() */
+
+typedef struct
+{
+    unsigned char mode, columns, rows;
+} screen_mode_info_t;   /* cx16_k_screen_mode_get() */
+
+/* Kernal-level functions */
+void cx16_k_clock_get_date_time(cx16_date_time_t *datetime_ptr);
+void cx16_k_clock_set_date_time(unsigned char year, unsigned char mon, unsigned char day, unsigned char hour, unsigned char min, unsigned char sec, unsigned char jif);
+unsigned char cx16_k_console_get_char(void);
+void cx16_k_console_init(unsigned int x, unsigned int y, unsigned int width, unsigned int height);
+void cx16_k_console_put_char(unsigned char c, unsigned char wrapwordflag);
+void cx16_k_console_put_image(void *imageaddr, unsigned int width, unsigned int height);
+void cx16_k_console_set_paging_message(void *msgaddr);
+void cx16_k_enter_basic(unsigned char coldstart) __attribute__((noreturn));
+unsigned long cx16_k_entropy_get(void); // returns 24-bit value
+void cx16_k_fb_cursor_next_line(unsigned int x);
+void cx16_k_fb_cursor_position(unsigned int x, unsigned int y);
+void cx16_k_fb_fill_pixels(unsigned int count, unsigned int step, unsigned char color);
+void cx16_k_fb_filter_pixels(void *filterfunc, unsigned int count);
+void cx16_k_fb_get_info(cx16_fb_info_t *info_ptr);
+unsigned char fb_get_pixel(void);
+void cx16_k_fb_get_pixels(void *pixeladdr, unsigned int count);
+void cx16_k_fb_init(void);
+void cx16_k_fb_move_pixels(unsigned int sx, unsigned int sy, unsigned int tx, unsigned int ty, unsigned int count);
+void cx16_k_fb_set_8_pixels(unsigned char pattern, unsigned char color);
+void cx16_k_fb_set_8_pixels_opaque(unsigned char pattern, unsigned char mask, unsigned char color1, unsigned char color2);
+void cx16_k_fb_set_palette(void *paladdr, unsigned char index, unsigned char count);
+void cx16_k_graph_clear(void);
+void cx16_k_graph_draw_image(unsigned int x, unsigned int y, void *imageaddr, unsigned int width, unsigned int height);
+void cx16_k_graph_draw_line(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2);
+void cx16_k_graph_draw_oval(unsigned int x, unsigned int y, unsigned int width, unsigned int height, unsigned int corner_radius, unsigned char fillflag);
+void cx16_k_graph_draw_rect(unsigned int x, unsigned int y, unsigned int width, unsigned int height, unsigned int corner_radius, unsigned char fillflag);
+long cx16_k_graph_get_char_size(unsigned char c, unsigned char style); // if printable returns info (0x00bbwwhh), else negative style byte (0xFF0000ss)
+void cx16_k_graph_init(graph_fb_functions_t *fb_funcs_ptr);
+void cx16_k_graph_move_rect(unsigned int sx, unsigned int sy, unsigned int tx, unsigned int ty, unsigned int width, unsigned int height);
+void cx16_k_graph_put_char(graph_pos_t *pos_ptr, unsigned char c);
+void cx16_k_graph_set_colors(unsigned char stroke, unsigned char fill, unsigned char background);
+void cx16_k_graph_set_font(void *fontaddr);
+void cx16_k_graph_set_window(unsigned int x, unsigned int y, unsigned int width, unsigned int height);
+int cx16_k_i2c_read_byte(unsigned char device, unsigned char offset); // returns negative on error
+int cx16_k_i2c_write_byte(unsigned char device, unsigned char offset, unsigned char byte); // return negative on error
+long cx16_k_joystick_get(unsigned char sticknum); // returns $YYYYXXAA (see docs, result negative if joystick not present)
+void cx16_k_joystick_scan(void);
+unsigned char cx16_k_kbdbuf_get_modifiers(void);
+int cx16_k_kbdbuf_peek(unsigned char *index_ptr); // returns negative if empty, if index_ptr non-NULL set contents to queue length
+void cx16_k_kbdbuf_put(unsigned char c);
+const char* cx16_k_keymap_get_id(void);
+unsigned char cx16_k_keymap_set(const char* identifier);	// returns 0 on success
+long cx16_k_macptr(unsigned char count, unsigned char noadvance, void *destaddr); // return negative if not supported
+void cx16_k_memory_copy(void *source, void *target, unsigned int num_bytes);
+unsigned int cx16_k_memory_crc(void *dataaddr, unsigned int num_bytes);
+void cx16_k_memory_decompress(void *inaddr, void *outaddr);
+void cx16_k_memory_fill(void *addr, unsigned int num_bytes, unsigned char value);
+void cx16_k_monitor(void) __attribute__((noreturn));
+void cx16_k_mouse_config(unsigned char showmouse, unsigned char xsize8, unsigned char ysize8);
+unsigned char cx16_k_mouse_get(mouse_pos_t *mouse_pos_ptr);	// returns mouse button byte
+void cx16_k_mouse_scan(void);
+unsigned char cx16_k_savehl(void *startaddr, void *endaddr_plusone); // returns 0 on success
+unsigned char cx16_k_screen_mode_get(screen_mode_info_t *info_ptr); // returns 0 on success
+unsigned char cx16_k_screen_mode_set(unsigned char mode); // returns 0 on success
+void cx16_k_screen_set_charset(unsigned char charset_type, void *charsetaddr);
+unsigned char cx16_k_sprite_set_image(unsigned char num, unsigned char w, unsigned char h, unsigned char maskflag, void *imageaddr, void *maskaddr, unsigned char bpp); // returns 0 on success
+unsigned char cx16_k_sprite_set_position(unsigned char sprnum, unsigned int xpos, unsigned int ypos); // returns 0 on success
+
+/* cc65 compatible cx16 functions */
+
+/* Return the number of 8K RAM banks that the machine has */
+/* at 0xA000-0xBFFF using MEMTOP (64=512K up to 256=2MB) */
+unsigned short get_numbanks(void); // return number of 8K RAM banks at 0xA000-0xBFFF (64=512K up to 256=2MB)
+
+/* Get the ROM build version.
+** -1 -- custom build
+** Negative -- prerelease build
+** Positive -- release build
+*/
+signed char get_ostype(void);  // return ROM build version (negative pre-release, -1=custom)
+
+/* Return the video signal type that the machine is using.
+** Return a TV_xx constant.
+*/
+unsigned char get_tv(void);    // return TV_* enum constant for current video signal type
+
+/* Set the video signal type that the machine will use.
+** Call with a TV_xx constant.
+** NOTE: Be careful, can overrides user setting for current monitor type (set in config menu)
+*/
+void set_tv(unsigned char type);    // set video signal type using TV_* enum constant
+
+/* Display the layers that are "named" by the bit flags in layers.
+** A value of 0b01 shows layer 0, a value of 0b10 shows layer 1,
+** a value of 0b11 shows both layers.  Return the previous value.
+*/
+unsigned char vera_layer_enable(unsigned char layers); // enable/disable VERA layers 0/1 (bits 0/1), returns previous
+
+/* Enable the sprite engine when mode is non-zero (true);
+** disable sprites when mode is zero.  Return the previous mode.
+*/
+unsigned char vera_sprites_enable(unsigned char enable); // enable/disable VERA sprites (0=off, non-zero=on), returns previous
+
+/* Set the video mode, return the old mode.
+** Return -1 if Mode isn't valid.
+** Call with one of the VIDEOMODE_xx constants.
+*/
+signed char videomode(signed char mode);   // set video mode using VIDEOMODE_* enum constant, returns previous or -1 if error
+
+/* Get a byte from a location in VERA's internal address space. */
+unsigned char vpeek(unsigned long addr);    // read byte from VERA VRAM address
+
+/* Put a byte into a location in VERA's internal address space.
+** (addr is second instead of first for the sake of code efficiency.)
+*/
+void vpoke(unsigned char data, unsigned long addr); // write byte value to VERA VRAM address
+
+void waitvsync(void);  // wait for the vertical blank interrupt
+
+#endif  // _CX16_H
+
diff --git a/mos-platform/cx16/cx16.inc b/mos-platform/cx16/cx16.inc
new file mode 100644
index 000000000..176765735
--- /dev/null
+++ b/mos-platform/cx16/cx16.inc
@@ -0,0 +1,237 @@
+; Copyright 2022 LLVM-MOS Project
+; Licensed under the Apache License, Version 2.0 with LLVM Exceptions.
+; See https://github.com/llvm-mos/llvm-mos-sdk/blob/main/LICENSE for license
+; information.
+
+; Commander X16 definitions
+
+; save X16 kernal registers (r6-r10) that llvm-mos needs preserved (rc20-rc29) using Y
+.macro X16_kernal_push_r6_r10
+	ldy	__r6
+	phy
+	ldy	__r6+1
+	phy
+	ldy	__r7
+	phy
+	ldy	__r7+1
+	phy
+	ldy	__r8
+	phy
+	ldy	__r8+1
+	phy
+	ldy	__r9
+	phy
+	ldy	__r9+1
+	phy
+	ldy	__r10
+	phy
+	ldy	__r10+1
+	phy
+.endm
+
+; restore X16 kernal registers (r6-r10) that llvm-mos needs preserved (rc20-rc29) using Y
+.macro X16_kernal_pop_r6_r10
+	ply
+	sty	__r10+1
+	ply
+	sty	__r10
+	ply
+	sty	__r9+1
+	ply
+	sty	__r9
+	ply
+	sty	__r8+1
+	ply
+	sty	__r8
+	ply
+	sty	__r7+1
+	ply
+	sty	__r7
+	ply
+	sty	__r6+1
+	ply
+	sty	__r6
+.endm
+
+; cx16 hardware I/O addresses (derived from x16-rom io.inc)
+; https://github.com/X16Community/x16-rom/blob/master/inc/io.inc
+
+ram_bank 			= 0		; read/write current RAM bank at $A000-$BFFF
+rom_bank 			= 1		; read/write current ROM bank at $C000-$FFFF
+
+IO_PAGE				= $9f		; I/O addresses are $9fxx
+
+via1				= $9f00         ; VIA 6522 #1
+d1prb				= (via1+0)
+d1pra				= (via1+1)
+d1ddrb				= (via1+2)
+d1ddra				= (via1+3)
+d1t1l				= (via1+4)
+d1t1h				= (via1+5)
+d1t1ll				= (via1+6)
+d1t1lh				= (via1+7)
+d1t2l				= (via1+8)
+d1t2h				= (via1+9)
+d1sr				= (via1+10)
+d1acr				= (via1+11)
+d1pcr				= (via1+12)
+d1ifr				= (via1+13)
+d1ier				= (via1+14)
+d1ora				= (via1+15)
+
+via2				= $9f10         ; VIA 6522 #2
+d2prb				= (via2+0)
+d2pra				= (via2+1)
+d2ddrb				= (via2+2)
+d2ddra				= (via2+3)
+d2t1l				= (via2+4)
+d2t1h				= (via2+5)
+d2t1ll				= (via2+6)
+d2t1lh				= (via2+7)
+d2t2l				= (via2+8)
+d2t2h				= (via2+9)
+d2sr				= (via2+10)
+d2acr				= (via2+11)
+d2pcr				= (via2+12)
+d2ifr				= (via2+13)
+d2ier				= (via2+14)
+d2ora				= (via2+15)
+
+YM_REG  			= $9F40		; YM2151 register address (read status)
+YM_DATA 			= $9F41		; YM2151 register datata (read status)
+
+; VERA info: https://github.com/X16Community/x16-docs/blob/master/VERA%20Programmer's%20Reference.md
+
+VERA_BASE 			= $9F20
+
+VERA_ADDR_L			= (VERA_BASE+$00)	; ADDRx_L
+VERA_ADDR_M			= (VERA_BASE+$01)	; ADDRx_M
+VERA_ADDR_H			= (VERA_BASE+$02)	; INCRx [7:4], DECRx [3], ADDRx_H [0] (x=ADDRSEL)
+VERA_DATA0  			= (VERA_BASE+$03)
+VERA_DATA1  			= (VERA_BASE+$04)
+VERA_CTRL   			= (VERA_BASE+$05)	; RESET [7], DCSEL[6:1], ADDRSEL[0]
+
+VERA_IEN       			= (VERA_BASE+$06)
+VERA_ISR       			= (VERA_BASE+$07)
+VERA_IRQ_LINE_L			= (VERA_BASE+$08)
+
+VERA_DC_VIDEO     		= (VERA_BASE+$09)	; DCSEL = 0
+VERA_DC_HSCALE    		= (VERA_BASE+$0A)	; DCSEL = 0
+VERA_DC_VSCALE    		= (VERA_BASE+$0B)	; DCSEL = 0
+VERA_DC_BORDER    		= (VERA_BASE+$0C)	; DCSEL = 0
+
+VERA_DC_HSTART    		= (VERA_BASE+$09)	; DCSEL = 1
+VERA_DC_HSTOP     		= (VERA_BASE+$0A)	; DCSEL = 1
+VERA_DC_VSTART    		= (VERA_BASE+$0B)	; DCSEL = 1
+VERA_DC_VSTOP     		= (VERA_BASE+$0C)	; DCSEL = 1
+
+VERA_L0_CONFIG    		= (VERA_BASE+$0D)
+VERA_L0_MAPBASE   		= (VERA_BASE+$0E)
+VERA_L0_TILEBASE  		= (VERA_BASE+$0F)
+VERA_L0_HSCROLL_L 		= (VERA_BASE+$10)
+VERA_L0_HSCROLL_H 		= (VERA_BASE+$11)
+VERA_L0_VSCROLL_L 		= (VERA_BASE+$12)
+VERA_L0_VSCROLL_H 		= (VERA_BASE+$13)
+
+VERA_L1_CONFIG    		= (VERA_BASE+$14)
+VERA_L1_MAPBASE   		= (VERA_BASE+$15)
+VERA_L1_TILEBASE  		= (VERA_BASE+$16)
+VERA_L1_HSCROLL_L 		= (VERA_BASE+$17)
+VERA_L1_HSCROLL_H 		= (VERA_BASE+$18)
+VERA_L1_VSCROLL_L 		= (VERA_BASE+$19)
+VERA_L1_VSCROLL_H 		= (VERA_BASE+$1A)
+
+VERA_AUDIO_CTRL   		= (VERA_BASE+$1B)
+VERA_AUDIO_RATE   		= (VERA_BASE+$1C)
+VERA_AUDIO_DATA   		= (VERA_BASE+$1D)
+
+VERA_SPI_DATA     		= (VERA_BASE+$1E)
+VERA_SPI_CTRL     		= (VERA_BASE+$1F)
+
+VERA_PSG_BASE     		= $1F9C0	; VERA address (writes also to VRAM for reads)
+VERA_PALETTE_BASE 		= $1FA00	; VERA address (writes also to VRAM for reads)
+VERA_SPRITES_BASE 		= $1FC00	; VERA address (writes also to VRAM for reads)
+
+;
+; VERA Video RAM Layout (ROM default)
+;
+; $0:0000 - $1:2BFF  320x240@256c Bitmap [320x200: - $0:F9FF]
+; $1:2C00 - $1:2FFF  -- unused --
+; $1:3000 - $1:AFFF  Sprites ($1000 per sprite)
+; $1:B000 - $1:EBFF  Text Mode
+; $1:EC00 - $1:EFFF  -- unused --
+; $1:F000 - $1:F7FF  Charset
+; $1:F800 - $1:F9BF  -- unused --
+; $1:F9C0 - $1:FFFF  Vera internal (PSG, pal, spr)
+
+fb_addr      			= $00000	; VERA address (64K aligned)
+sprite_addr  			= $13000	; VERA address (sprite data)
+screen_addr  			= $1b000	; VERA address (text screen base)
+charset_addr 			= $1f000	; VERA address (charset base)
+
+; ---------------------------------------------------------------------------
+; CX16 mostly Commodore C64 compatible kernal variables
+; (unofficial ones are defined by cc65, but best to avoid)
+;
+; unofficial kernal zero-page variables
+KTEMP2                    	= $80
+FNAM                      	= $8A
+TXTPTR                    	= $EE
+
+; unofficial kernal variables
+BASIC_BUF                     	= $0200
+SCREEN_PTR                    	= $0262
+STATUS                        	= $0287
+IN_DEV                        	= $028B
+OUT_DEV                       	= $028C
+FNAM_LEN                      	= $028F
+SECADR                        	= $0291
+DEVADR                        	= $0292
+
+; documented kernal vectors
+CINV                          	= $0314
+CBINV                         	= $0316
+NMINV                         	= $0318
+IOPEN                         	= $031A
+ICLOSE                        	= $031C
+ICHKIN                        	= $031E
+ICKOUT                        	= $0320
+ICLRCH                        	= $0322
+IBASIN                        	= $0324
+IBSOUT                        	= $0326
+ISTOP                         	= $0328
+IGETIN                        	= $032A
+ICLALL                        	= $032C
+ILOAD                         	= $0330
+ISAVE                         	= $0332
+
+; unofficial kernal variables
+CURS_COLOR                    	= $0373
+CHARCOLOR                     	= $0376
+RVS                           	= $0377
+CURS_FLAG                     	= $037B
+CURS_BLINK                    	= $037C
+CURS_CHAR                     	= $037D
+CURS_STATE                    	= $037E
+CURS_X                        	= $0380
+CURS_Y                        	= $0383
+LLEN                          	= $0386
+NLINES                        	= $0387
+VARTAB                        	= $03E1
+MEMSIZ                        	= $03E9
+
+; CX16 framebuffer vectors
+I_FB_INIT                     	= $02E4
+I_FB_GET_INFO                 	= $02E6
+I_FB_SET_PALETTE              	= $02E8
+I_FB_CURSOR_POSITION          	= $02EA
+I_FB_CURSOR_NEXT_LINE         	= $02EC
+I_FB_GET_PIXEL                	= $02EE
+I_FB_GET_PIXELS               	= $02F0
+I_FB_SET_PIXEL                	= $02F2
+I_FB_SET_PIXELS               	= $02F4
+I_FB_SET_8_PIXELS             	= $02F6
+I_FB_SET_8_PIXELS_OPAQUE	= $02F8
+I_FB_FILL_PIXELS              	= $02FA
+I_FB_FILTER_PIXELS            	= $02FC
+I_FB_MOVE_PIXELS              	= $02FE
diff --git a/mos-platform/cx16/cx16_k_clock_get_date_time.s b/mos-platform/cx16/cx16_k_clock_get_date_time.s
new file mode 100644
index 000000000..d70cc1844
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_clock_get_date_time.s
@@ -0,0 +1,30 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; typedef struct { unsigned char year, mon, day, hour, min, sec, jif; } cx16_date_time_t;
+; void cx16_k_clock_get_date_time(cx16_date_time_t *datetime_ptr);
+;                                                   rc2/3
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-clock_get_date_time
+;
+.global cx16_k_clock_get_date_time
+cx16_k_clock_get_date_time:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	ldy	__rc2			; push datetime_ptr
+	phy
+	ldy	__rc2+1
+	phy
+	jsr	__CLOCK_GET_DATE_TIME
+	ply				; pop datetime_ptr to r4
+	sty	__r4+1
+	ply
+	sty	__r4
+	ldy	#7-1			; copy 7 bytes of data
+1:	lda	__r0,y
+	sta	(__r4),y
+	dey
+	bpl	1b
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_clock_set_date_time.s b/mos-platform/cx16/cx16_k_clock_set_date_time.s
new file mode 100644
index 000000000..9f57662ae
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_clock_set_date_time.s
@@ -0,0 +1,31 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_clock_set_date_time(unsigned char year, unsigned char mon, unsigned char day, unsigned char hour, unsigned char min, unsigned char sec, unsigned char jif);
+; llvm-mos:                                     A                   X                  rc2                rc3                 rc4                rc5                rc6
+; llvm-mos aliases:                             A                   X                  r0L                r0H                 r1L                r1H                r2L
+; X16 kernal:                                   r0L                 r0H                r1L                r1H                 r2L                r2H                r3L
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-clock_set_date_time
+;
+.global cx16_k_clock_set_date_time
+cx16_k_clock_set_date_time:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	ldy	__rc6		; NOTE: copy args backwards due to overlap
+	sty	__r3		; r3L = jif
+	ldy	__rc5
+	sty	__r2+1		; r2H = sec
+	ldy	__rc4
+	sty	__r2		; r2L = min
+	ldy	__rc3
+	sty	__r1+1		; r1H = hour
+	ldy	__rc2
+	sty	__r1		; r1L = day
+	stx	__r0+1		; r0H = month
+	sta	__r0		; r0L = year
+	jsr	__CLOCK_SET_DATE_TIME
+	X16_kernal_pop_r6_r10	; assuming additional regs trashed (paranoia)
+	rts
+
diff --git a/mos-platform/cx16/cx16_k_console_get_char.s b/mos-platform/cx16/cx16_k_console_get_char.s
new file mode 100644
index 000000000..e631a8358
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_console_get_char.s
@@ -0,0 +1,15 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned char cx16_k_console_get_char(void);
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-console_get_char
+;
+.global cx16_k_console_get_char
+cx16_k_console_get_char:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	jsr	__CONSOLE_GET_CHAR
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_console_init.s b/mos-platform/cx16/cx16_k_console_init.s
new file mode 100644
index 000000000..142f258a3
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_console_init.s
@@ -0,0 +1,32 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_console_init(unsigned int x, unsigned int y, unsigned int width, unsigned int height);
+; llvm-mos:                           A/X           rc2/3               rc4/5               rc6/7
+; llvm-mos aliases:                   A/X           r0                  r1                  r2
+; X16 kernal:                         r0            r1                  r2                  r3
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-console_init
+;
+.global cx16_k_console_init
+cx16_k_console_init:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	ldy	__rc6		; NOTE: copy args backwards due to overlap
+	sty	__r3		; r3 = height
+	ldy	__rc6+1
+	sty	__r3+1
+	ldy	__rc4
+	sty	__r2		; r3 = width
+	ldy	__rc4+1
+	sty	__r2+1
+	ldy	__rc2
+	sty	__r1		; r3 = y
+	ldy	__rc2+1
+	sty	__r1+1
+	sta	__r0		; r0 = x
+	stx	__r0+1
+	jsr	__CONSOLE_INIT
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_console_put_char.s b/mos-platform/cx16/cx16_k_console_put_char.s
new file mode 100644
index 000000000..e43940950
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_console_put_char.s
@@ -0,0 +1,19 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_console_put_char(unsigned char c, unsigned char wrapwordflag);
+; llvm-mos:                                  A                X
+; X16 kernal:                                A                C
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-console_put_char
+;
+.global cx16_k_console_put_char
+cx16_k_console_put_char:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+				; A = c
+	cpx	#1		; C = set if wrapwordflag >= 1
+	jsr	__CONSOLE_PUT_CHAR
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_console_put_image.s b/mos-platform/cx16/cx16_k_console_put_image.s
new file mode 100644
index 000000000..62b2bf588
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_console_put_image.s
@@ -0,0 +1,25 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_console_put_image(void *imageaddr, unsigned int width, unsigned int height);
+; llvm-mos:                           rc2/3                   A/X                 rc4/5
+; llvm-mos aliases:                   r0                      A/X                 r1
+; X16 kernal:                         r0                      r1                  r2
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-console_put_image
+;
+.global cx16_k_console_put_image
+cx16_k_console_put_image:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	ldy	__rc4
+	sty	__r2		; r2 = height
+	ldy	__rc4+1
+	sty	__r2+1
+	sta	__r1		; r1 = width
+	stx	__r1+1
+				; r0 = imageaddr (already set)
+	jsr	__CONSOLE_PUT_IMAGE
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_console_set_paging_message.s b/mos-platform/cx16/cx16_k_console_set_paging_message.s
new file mode 100644
index 000000000..1d1cce59d
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_console_set_paging_message.s
@@ -0,0 +1,19 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_console_set_paging_message(void *msgaddr);
+; llvm-mos:                                    rc2/3
+; llvm-mos aliases:                            r0
+; X16 kernal:                                  r0
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-console_set_paging_message
+;
+.global cx16_k_console_set_paging_message
+cx16_k_console_set_paging_message:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+    					; r0 = addr (already set)
+	jsr	__CONSOLE_SET_PAGE_MSG
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_enter_basic.s b/mos-platform/cx16/cx16_k_enter_basic.s
new file mode 100644
index 000000000..b1257cee2
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_enter_basic.s
@@ -0,0 +1,14 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_enter_basic(unsigned char coldstart) __attribute__((noreturn));
+;                                       A
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-enter_basic
+;
+.global cx16_k_enter_basic
+cx16_k_enter_basic:
+	cmp	#1		; set carry if coldstart >= 1
+	jmp	__ENTER_BASIC
diff --git a/mos-platform/cx16/cx16_k_entropy_get.s b/mos-platform/cx16/cx16_k_entropy_get.s
new file mode 100644
index 000000000..b1994ed71
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_entropy_get.s
@@ -0,0 +1,16 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned long cx16_k_entropy_get(void); // returns 24-bit value
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-entropy_get
+;
+.global cx16_k_entropy_get
+cx16_k_entropy_get:
+	jsr	__ENTROPY_GET
+	stz	__rc2+1		; zero [31:24]
+	sty	__rc2		; set  [23:16]
+				; A/X  [15:0]
+	rts
diff --git a/mos-platform/cx16/cx16_k_fb_cursor_next_line.s b/mos-platform/cx16/cx16_k_fb_cursor_next_line.s
new file mode 100644
index 000000000..ac82e9d5d
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_cursor_next_line.s
@@ -0,0 +1,17 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_fb_cursor_next_line(unsigned int x);
+; llvm-mos:                                  A/X
+; llvm-mos alias:                            A/X
+; X16 kernal:                                r0
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_cursor_next_line
+;
+.global cx16_k_fb_cursor_next_line
+cx16_k_fb_cursor_next_line:
+	sta	__r0		; __r0 = x
+	stx	__r0+1
+	jmp	__FB_CURSOR_NEXT_LINE
diff --git a/mos-platform/cx16/cx16_k_fb_cursor_position.s b/mos-platform/cx16/cx16_k_fb_cursor_position.s
new file mode 100644
index 000000000..e48b9cafb
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_cursor_position.s
@@ -0,0 +1,21 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_fb_cursor_position(unsigned int x, unsigned int y);
+; llvm-mos:                                 A/X           rc2/3
+; llvm-mos aliases:                         A/X           r0
+; X16 kernal:                               r0            r1
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_cursor_position
+;
+.global cx16_k_fb_cursor_position
+cx16_k_fb_cursor_position:
+	ldy	__rc2		; NOTE: copy args backwards due to overlap
+	sty	__r1		; r1 = y
+	ldy	__rc2+1
+	sty	__r1+1
+	sta	__r0		; r0 = x
+	stx	__r0+1
+	jmp	__FB_CURSOR_POSITION
diff --git a/mos-platform/cx16/cx16_k_fb_fill_pixels.s b/mos-platform/cx16/cx16_k_fb_fill_pixels.s
new file mode 100644
index 000000000..cc65b01f8
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_fill_pixels.s
@@ -0,0 +1,22 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_fb_fill_pixels(unsigned int count, unsigned int step, unsigned char color);
+; llvm-mos:                               A/X                rc2/3                rc4
+; llvm-mos aliases:                       A/X                r0                   r1L
+; X16 kernal:                             r0                 r1                   A
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_fill_pixels
+;
+.global cx16_k_fb_fill_pixels
+cx16_k_fb_fill_pixels:
+	ldy	__rc2		; NOTE: copy args backwards due to overlap
+	sty	__r1		; r1 = step
+	ldy	__rc2+1
+	sty	__r1+1
+	sta	__r0		; r0 = count
+	stx	__r0+1
+	lda	__rc4		; A = color
+	jmp	__FB_FILL_PIXELS
diff --git a/mos-platform/cx16/cx16_k_fb_filter_pixels.s b/mos-platform/cx16/cx16_k_fb_filter_pixels.s
new file mode 100644
index 000000000..b4209d4dc
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_filter_pixels.s
@@ -0,0 +1,18 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_fb_filter_pixels(void *filterfunc, unsigned int count);
+; llvm-mos:                            rc2/3                    A/X
+; llvm-mos aliases:                    r0                       A/X
+; X16 kernal:                          r0                       r1
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_filter_pixels
+;
+.global cx16_k_fb_filter_pixels
+cx16_k_fb_filter_pixels:
+				; r0 = filterfunc (already set)
+	sta	__r1		; r1 = count
+	stx	__r1+1
+	jmp	__FB_FILTER_PIXELS
diff --git a/mos-platform/cx16/cx16_k_fb_get_info.s b/mos-platform/cx16/cx16_k_fb_get_info.s
new file mode 100644
index 000000000..44a2320b8
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_get_info.s
@@ -0,0 +1,30 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; typedef struct { unsigned int width, height; unsigned char depth; } cx16_fb_info_t;
+; void cx16_k_fb_get_info(cx16_fb_info_t *info_ptr);
+; llvm-mos:                               rc2/3
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_get_info
+;
+.global cx16_k_fb_get_info
+cx16_k_fb_get_info:
+	ldy	__rc2			; push info_ptr
+	phy
+	ldy	__rc2+1
+	phy
+	jsr	__FB_GET_INFO
+	ply				; pop info_ptr to r4
+	sta	__r4+1
+	ply
+	sta	__r4
+	ldy	#5-1		; offset to depth
+	sta	(__r4),y	; store depth to info_ptr
+	dey			; copy remaining 4 bytes
+1:	lda	__r0,y		; from r0 & r1
+	sta	(__r4),y	; to info_ptr
+	dey
+	bpl	1b
+	rts
diff --git a/mos-platform/cx16/cx16_k_fb_get_pixel.s b/mos-platform/cx16/cx16_k_fb_get_pixel.s
new file mode 100644
index 000000000..5b05486af
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_get_pixel.s
@@ -0,0 +1,14 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned char cx16_k_fb_get_pixel(void);
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_get_pixel
+;
+.global cx16_k_fb_get_pixel
+cx16_k_fb_get_pixel:
+	jsr	__FB_GET_PIXEL
+	ldx	#0
+	rts
diff --git a/mos-platform/cx16/cx16_k_fb_get_pixels.s b/mos-platform/cx16/cx16_k_fb_get_pixels.s
new file mode 100644
index 000000000..953679236
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_get_pixels.s
@@ -0,0 +1,18 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_fb_get_pixels(void *pixeladdr, unsigned int count);
+; llvm-mos:                       rc2/3                   A/X
+; llvm-mos aliases:               r0                      A/X
+; X16 kernal:                     r0                      r1
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_get_pixels
+;
+.global cx16_k_fb_get_pixels
+cx16_k_fb_get_pixels:
+				; r0 = pixeladdr (already set)
+	sta	__r1		; r1 = count
+	stx	__r1+1
+	jmp	__FB_GET_PIXELS
diff --git a/mos-platform/cx16/cx16_k_fb_init.s b/mos-platform/cx16/cx16_k_fb_init.s
new file mode 100644
index 000000000..a03a9418f
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_init.s
@@ -0,0 +1,13 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_fb_init(void);
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_init
+;
+.global cx16_k_fb_init
+cx16_k_fb_init:
+	jmp	__FB_INIT
+
diff --git a/mos-platform/cx16/cx16_k_fb_move_pixels.s b/mos-platform/cx16/cx16_k_fb_move_pixels.s
new file mode 100644
index 000000000..a0b9c75e8
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_move_pixels.s
@@ -0,0 +1,33 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_fb_fill_pixels(unsigned int sx, unsigned int sy, unsigned int tx, unsigned int ty, unsigned int count);
+; llvm-mos:                              A/X            rc2/3            rc4/5            rc6/7               rc8/9
+; llvm-mos aliases:                      A/X            r0               r1               r2                  r3
+; X16 kernal:                            r0             r1               r2               r3                  r4
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_move_pixels
+;
+.global cx16_k_fb_fill_pixels
+cx16_k_fb_fill_pixels:
+	ldy	__rc8		; NOTE: copy args backwards due to overlap
+	sty	__r4		; r4 = count
+	ldy	__rc8+1
+	sty	__r4+1
+	ldy	__rc6
+	sty	__r3		; r3 = height
+	ldy	__rc6+1
+	sty	__r3+1
+	ldy	__rc4
+	sty	__r2		; r2 = width
+	ldy	__rc4+1
+	sty	__r2+1
+	ldy	__rc2
+	sty	__r1		; r1 = y
+	ldy	__rc2+1
+	sty	__r1+1
+	sta	__r0		; r0 = x
+	stx	__r0+1
+	jmp	__FB_MOVE_PIXELS
diff --git a/mos-platform/cx16/cx16_k_fb_set_8_pixels.s b/mos-platform/cx16/cx16_k_fb_set_8_pixels.s
new file mode 100644
index 000000000..0a97dcc67
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_set_8_pixels.s
@@ -0,0 +1,16 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_fb_set_8_pixels(unsigned char pattern, unsigned char color);
+; llvm-mos:                                 A                      X
+; X16 kernal:                               A                      X
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_set_8_pixels
+;
+.global cx16_k_fb_set_8_pixels
+cx16_k_fb_set_8_pixels:
+				; a = pattern (already set)
+				; x = color (already set)
+	jmp __FB_SET_8_PIXELS
diff --git a/mos-platform/cx16/cx16_k_fb_set_8_pixels_opaque.s b/mos-platform/cx16/cx16_k_fb_set_8_pixels_opaque.s
new file mode 100644
index 000000000..28df9e6ff
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_set_8_pixels_opaque.s
@@ -0,0 +1,19 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_fb_set_8_pixels_opaque(unsigned char pattern, unsigned char mask, unsigned char color1, unsigned char color2);
+; llvm-mos:                                        A                      X                   rc2                   rc3
+; llvm-mos aliases:                                A                      X                   r0L                   r0H
+; X16 kernal:                                      A                      r0L                 X                     Y
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_set_8_pixels_opaque
+;
+.global cx16_k_fb_set_8_pixels_opaque
+cx16_k_fb_set_8_pixels_opaque:
+	stx	__r0		; r0L = mask
+	ldx	__rc2		; X = color1
+	ldy	__rc3		; Y = color2
+				; A = pattern (already set)
+	jmp	__FB_SET_8_PIXELS_OPAQUE
diff --git a/mos-platform/cx16/cx16_k_fb_set_palette.s b/mos-platform/cx16/cx16_k_fb_set_palette.s
new file mode 100644
index 000000000..ab145f37c
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_fb_set_palette.s
@@ -0,0 +1,18 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void fb_set_palette(void *paladdr, unsigned char index, unsigned char count);
+; llvm-mos:                 rc2/3                  A                    X
+; llvm-mos aliases:         r0                     A                    X
+; X16 kernal:               r0                     A                    X
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-fb_set_palette
+;
+.global cx16_k_fb_set_palette
+cx16_k_fb_set_palette:
+				; r0 = paladdr (already set)
+				; A = index (already set)
+				; X = count (already set)
+	jmp	__FB_SET_PALETTE
diff --git a/mos-platform/cx16/cx16_k_graph_clear.s b/mos-platform/cx16/cx16_k_graph_clear.s
new file mode 100644
index 000000000..a2cbcc49b
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_clear.s
@@ -0,0 +1,16 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_graph_clear(void);
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_clear
+;
+.global cx16_k_graph_clear
+cx16_k_graph_clear:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	jsr	__GRAPH_CLEAR
+	X16_kernal_pop_r6_r10
+	rts
+
diff --git a/mos-platform/cx16/cx16_k_graph_draw_image.s b/mos-platform/cx16/cx16_k_graph_draw_image.s
new file mode 100644
index 000000000..e537c8582
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_draw_image.s
@@ -0,0 +1,36 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_graph_draw_image(unsigned int x, unsigned int y, void *imageaddr, unsigned int width, unsigned int height);
+; llvm-mos:                               A/X           rc2/3        rc4/5                   rc6/7               rc8/9
+; llvm-mos aliases:			  A/X           r0           r1                      r2                  r3
+; X16 kernal:                             r0            r1           r2                      r3                  r4
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_draw_image
+;
+.global cx16_k_graph_draw_image
+cx16_k_graph_draw_image:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	ldy	__rc8		; NOTE: copy args backwards due to overlap
+	sty	__r4		; r4 = height
+	ldy	__rc8+1
+	sty	__r4+1
+	ldy	__rc6
+	sty	__r3		; r3 = width
+	ldy	__rc6+1
+	sty	__r3+1
+	ldy	__rc4
+	sty	__r2		; r2 = ptr
+	ldy	__rc4+1
+	sty	__r2+1
+	ldy	__rc2
+	sty	__r1		; r3 = y
+	ldy	__rc2+1
+	sty	__r1+1
+	sta	__r0		; r0 = x
+	stx	__r0+1
+	jsr	__GRAPH_DRAW_IMAGE
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_graph_draw_line.s b/mos-platform/cx16/cx16_k_graph_draw_line.s
new file mode 100644
index 000000000..9769336b3
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_draw_line.s
@@ -0,0 +1,32 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_graph_draw_line(unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2);
+; llvm-mos                                A/X            rc2/3            rc4/5            rc6/7
+; llvm-mos aliases:                       A/X            r0               r1               r2
+; X16 kernal:                             r0             r1               r2               r3
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_draw_line
+;
+.global cx16_k_graph_draw_line
+cx16_k_graph_draw_line:
+	X16_kernal_push_r6_r10	; documented as trashing additional regs
+	ldy	__rc6		; NOTE: copy args backwards due to overlap
+	sty	__r3		; __r3 = y2
+	ldy	__rc6+1
+	sty	__r3+1
+	ldy	__rc4
+	sty	__r2		; __r2 = x2
+	ldy	__rc4+1
+	sty	__r2+1
+	ldy	__rc2
+	sty	__r1		; __r1 = y1
+	ldy	__rc2+1
+	sty	__r1+1
+	sta	__r0		; __r0 = x1
+	stx	__r0+1
+	jsr	__GRAPH_DRAW_LINE
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_graph_draw_oval.s b/mos-platform/cx16/cx16_k_graph_draw_oval.s
new file mode 100644
index 000000000..9af701c4b
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_draw_oval.s
@@ -0,0 +1,34 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_graph_draw_oval(unsigned int x, unsigned int y, unsigned int width, unsigned int height, unsigned char fillflag);
+; llvm-mos                               A/X           rc2/3               rc4/5               rc6/7                 r8
+; llvm-mos aliases:                      A/X           r0                  r1                  r2                    r3L
+; X16 kernal:                             r0           r1                  r2                  r3                    C
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_draw_oval
+;
+.global cx16_k_graph_draw_oval
+cx16_k_graph_draw_oval:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	ldy	__rc8		; load fillflag
+	cpy	#1		; C = set if fillflag >= 1
+	ldy	__rc6		; NOTE: copy args backwards due to overlap
+	sty	__r3		; r3 = height
+	ldy	__rc6+1
+	sty	__r3+1
+	ldy	__rc4
+	sty	__r2		; r2 = width
+	ldy	__rc4+1
+	sty	__r2+1
+	ldy	__rc2
+	sty	__r1		; r1 = y
+	ldy	__rc2+1
+	sty	__r1+1
+	sta	__r0		; r0 = x
+	stx	__r0+1
+	jsr	__GRAPH_DRAW_OVAL
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_graph_draw_rect.s b/mos-platform/cx16/cx16_k_graph_draw_rect.s
new file mode 100644
index 000000000..e1c3c233d
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_draw_rect.s
@@ -0,0 +1,38 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_graph_draw_rect(unsigned int x, unsigned int y, unsigned int width, unsigned int height, unsigned int corner_radius, unsigned char fillflag);
+; llvm-mos                               A/X           rc2/3               rc4/5               rc6/7                 r8/9                        rc10
+; llvm-mos aliases:                      A/X           r0                  r1                  r2                    r3                          r4L
+; X16 kernal:                             r0           r1                  r2                  r3                    r4                          C
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_draw_rect
+;
+.global cx16_k_graph_draw_rect
+cx16_k_graph_draw_rect:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	ldy	__rc10		; load fillflag
+	cpy	#1		; C = set if fillflag >= 1
+	ldy	__rc8		; NOTE: copy args backwards due to overlap
+	sty	__r4		; r4 = corner_radius
+	ldy	__rc8+1
+	sty	__r4+1
+	ldy	__rc6
+	sty	__r3		; r3 = height
+	ldy	__rc6+1
+	sty	__r3+1
+	ldy	__rc4
+	sty	__r2		; r2 = width
+	ldy	__rc4+1
+	sty	__r2+1
+	ldy	__rc2
+	sty	__r1		; r3 = y
+	ldy	__rc2+1
+	sty	__r1+1
+	sta	__r0		; r0 = x
+	stx	__r0+1
+	jsr	__GRAPH_DRAW_RECT
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_graph_get_char_size.s b/mos-platform/cx16/cx16_k_graph_get_char_size.s
new file mode 100644
index 000000000..8ee7a7700
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_get_char_size.s
@@ -0,0 +1,31 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; long cx16_k_graph_get_char_size(unsigned char c, unsigned char style); // if printable returns info (0x00bbwwhh), else negative style byte (0xFF0000ss)
+; llvm-mos:                                     A                X
+; X16-kernal:                                   A                X
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_get_char_size
+;
+.global cx16_k_graph_get_char_size
+cx16_k_graph_get_char_baseline:
+	X16_kernal_push_r6_r10	; appears to trash additional registers
+				; A = c (already set)
+				; X = format (already set)
+	jsr	__GRAPH_GET_CHAR_SIZE
+	stz	__rc3		; upper byte 0
+	bcc	1f		; branch if is printable char
+	dec	__rc3		; upper byte $FF
+	stz	__rc2
+	tya			; set 0xFF0000ss style from Y
+	ldx	#0
+	rts
+1:	sta	__rc2		; set 0x00bbxxxx baseline offset from A
+	phx			; save width from X
+	tya
+	tax			; set 0x00xxhhxx height from Y
+	pla			; set 0x00xxxxww width
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_graph_init.s b/mos-platform/cx16/cx16_k_graph_init.s
new file mode 100644
index 000000000..81bef633f
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_init.s
@@ -0,0 +1,32 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; typedef struct { void *fb_init;
+;		   void *fb_get_info;
+;                  void *fb_set_palette;
+;                  void *fb_cursor_position;
+;	           void *fb_cursor_next_line;
+;		   void *fb_get_pixel;
+;                  void *fb_get_pixels;
+;                  void *fb_set_pixel;
+;                  void *fb_set_pixels;
+;                  void *fb_set_8_pixels;
+;                  void *fb_set_8_pixels_opaque;
+;                  void *fb_fill_pixels;
+;                  void *fb_filter_pixels;
+;                  void *fb_move_pixels;
+;                } graph_fb_functions_t;
+; void cx16_k_graph_init(graph_fb_functions_t *fb_funcs_ptr);
+; llvm-mos:                                    rc2/3
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_init
+;
+.global cx16_k_graph_init
+cx16_k_graph_init:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+				; r0 = fb_vector_table (already set)
+	jsr	__GRAPH_INIT
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_graph_move_rect.s b/mos-platform/cx16/cx16_k_graph_move_rect.s
new file mode 100644
index 000000000..05b33981a
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_move_rect.s
@@ -0,0 +1,40 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_graph_move_rect(unsigned int sx, unsigned int sy, unsigned int tx, unsigned int ty, unsigned int width, unsigned int height);
+; llvm-mos                                A/X            rc2/3            rc4/5            rc6/7               r8/9                rc10/11
+; llvm-mos aliases:                       A/X            r0               r1               r2                  r3                  r4
+; X16 kernal:                              r0            r1               r2               r3                  r4                  r5
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_move_rect
+;
+.global cx16_k_graph_move_rect
+cx16_k_graph_move_rect:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	ldy	__rc10		; NOTE: copy args backwards due to overlap
+	sty	__r5		; r5 = height
+	ldy	__rc10+1
+	sty	__r5+1
+	ldy	__rc8
+	sty	__r4		; r4 = width
+	ldy	__rc8+1
+	sty	__r4+1
+	ldy	__rc6
+	sty	__r3		; r3 = ty
+	ldy	__rc6+1
+	sty	__r3+1
+	ldy	__rc4
+	sty	__r2		; r2 = tx
+	ldy	__rc4+1
+	sty	__r2+1
+	ldy	__rc2
+	sty	__r1		; r1 = y
+	ldy	__rc2+1
+	sty	__r1+1
+	sta	__r0		; r0 = x
+	stx	__r0+1
+	jsr	__GRAPH_MOVE_RECT
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_graph_put_char.s b/mos-platform/cx16/cx16_k_graph_put_char.s
new file mode 100644
index 000000000..8dbe5e8dc
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_put_char.s
@@ -0,0 +1,40 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; typedef struct { int x, y } graph_pos_t;
+; void cx16_k_graph_put_char(graph_pos_t *pos_ptr, unsigned char c);
+; llvm-mos:                               rc2/3                  A
+; llvm-mos aliases:                       r0                     A
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_put_char
+;
+.global cx16_k_graph_put_char
+cx16_k_graph_put_char:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	ldy	__rc2		; push rc2/3
+	sty	__r4
+	phy
+	ldy	__rc2+1
+	sty	__r4+1
+	phy
+	tax			; save c
+	ldy	#4-1		; copy 4 bytes
+1:	lda	(__r4),y	; from pos_ptr x, y
+	sta	__r0,y		; to r0 & r1
+	dey
+	bpl	1b
+	txa			; A = c
+	jsr	__GRAPH_PUT_CHAR
+	ply
+	sty	__r4+1
+	ply
+	sty	__r4
+	ldy	#4-1		; copy 4 bytes
+2:	lda	__r0,y		; from r0 & r1
+	sta	(__r4),y	; to pos_ptr x, y
+	dey
+	bpl	2b
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_graph_set_colors.s b/mos-platform/cx16/cx16_k_graph_set_colors.s
new file mode 100644
index 000000000..712fe1eeb
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_set_colors.s
@@ -0,0 +1,20 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_graph_set_colors(unsigned char stroke, unsigned char fill, unsigned char background);
+; llvm-mos:                                  A                     X                   rc2
+; X16-kernal:                                A                     X                   Y
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_set_colors
+;
+.global cx16_k_graph_set_colors
+cx16_k_graph_set_colors:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+				; A = stroke (already set)
+				; X = fill (already set)
+	ldy	__rc2		; Y = background
+	jsr	__GRAPH_SET_COLORS
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_graph_set_font.s b/mos-platform/cx16/cx16_k_graph_set_font.s
new file mode 100644
index 000000000..af94b5a10
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_set_font.s
@@ -0,0 +1,17 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_graph_set_font(void *fontaddr);
+; llvm-mos:                        rc2/3
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_set_font
+;
+.global cx16_k_graph_set_font
+cx16_k_graph_set_font:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+				; r0 = fontaddr (already present)
+	jsr	__GRAPH_SET_FONT
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_graph_set_window.s b/mos-platform/cx16/cx16_k_graph_set_window.s
new file mode 100644
index 000000000..25032eaad
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_graph_set_window.s
@@ -0,0 +1,32 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_graph_set_window(unsigned int x, unsigned int y, unsigned int width, unsigned int height);
+; llvm-mos                                A/X           rc2/3               rc4/5               rc6/7
+; llvm-mos aliases:                       A/X           r0                  r1                  r2
+; X16 kernal:                             r0            r1                  r2                  r3
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-graph_set_window
+;
+.global cx16_k_graph_set_window
+cx16_k_graph_set_window:
+	X16_kernal_push_r6_r10	; assuming additional regs trashed (paranoia)
+	ldy	__rc6		; NOTE: copy args backwards due to overlap
+	sty	__r3		; r3 = height
+	ldy	__rc6+1
+	sty	__r3+1
+	ldy	__rc4
+	sty	__r2		; r2 = width
+	ldy	__rc4+1
+	sty	__r2+1
+	ldy	__rc2
+	sty	__r1		; r1 = y
+	ldy	__rc2+1
+	sty	__r1+1
+	sta	__r0		; r0 = x
+	stx	__r0+1
+	jsr	__GRAPH_SET_WINDOW
+	X16_kernal_pop_r6_r10
+	rts
diff --git a/mos-platform/cx16/cx16_k_i2c_read_byte.s b/mos-platform/cx16/cx16_k_i2c_read_byte.s
new file mode 100644
index 000000000..7ba3c9e85
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_i2c_read_byte.s
@@ -0,0 +1,23 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; int cx16_k_i2c_read_byte(unsigned char device, unsigned char offset); // returns negative on error
+; llvm-mos:                              A                     X
+; X16-kernal:                            X                     Y
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-i2c_read_byte
+;
+.global cx16_k_i2c_read_byte
+cx16_k_i2c_read_byte:
+	sta	__rc2
+	txa
+	ldx	__rc2		; X = device
+	tay			; Y = offset
+	jsr	__I2C_READ_BYTE
+	ldx	#$0
+	bcc	1f		; branch if no error
+	dex			; return -1 on error
+	txa
+1:	rts
diff --git a/mos-platform/cx16/cx16_k_i2c_write_byte.s b/mos-platform/cx16/cx16_k_i2c_write_byte.s
new file mode 100644
index 000000000..00e001fa9
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_i2c_write_byte.s
@@ -0,0 +1,24 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; int cx16_k_i2c_write_byte(unsigned char device, unsigned char offset, unsigned char byte); // return negative on error
+; llvm-mos:                               A                     X                     rc2
+; X16 kernal:                             X                     Y                     A
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-i2c_write_byte
+;
+.global cx16_k_i2c_write_byte
+cx16_k_i2c_write_byte:
+	sta	__rc3		; save device
+	stx	__rc4		; save offset
+	lda	__rc2		; A = byte
+	ldy	__rc4		; Y = offset
+	ldx	__rc3		; X = device
+	jsr	__I2C_WRITE_BYTE
+	ldx	#0
+	bcc	1f		; branch if no error
+	dex			; return -1 on error
+1:	txa			; 0 or -1
+	rts
diff --git a/mos-platform/cx16/cx16_k_joystick_get.s b/mos-platform/cx16/cx16_k_joystick_get.s
new file mode 100644
index 000000000..bef64ef6c
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_joystick_get.s
@@ -0,0 +1,18 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; long cx16_k_joystick_get(unsigned char sticknum); // returns $YYYYXXAA (see docs, result negative if joystick not present)
+; llvm-mos:                              A
+; X16 kernal:                            A
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-joystick_get
+;
+.global cx16_k_joystick_get
+cx16_k_joystick_get:
+				; A = sticknum (already set)
+	jsr	__JOYSTICK_GET
+	sty	__rc2
+	sty	__rc3
+	rts
diff --git a/mos-platform/cx16/cx16_k_joystick_scan.s b/mos-platform/cx16/cx16_k_joystick_scan.s
new file mode 100644
index 000000000..a339d0c90
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_joystick_scan.s
@@ -0,0 +1,12 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_joystick_scan(void);
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-joystick_scan
+;
+.global cx16_k_joystick_scan
+cx16_k_joystick_scan:
+	jmp	__JOYSTICK_SCAN
diff --git a/mos-platform/cx16/cx16_k_kbdbuf_get_modifiers.s b/mos-platform/cx16/cx16_k_kbdbuf_get_modifiers.s
new file mode 100644
index 000000000..2cb295f9d
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_kbdbuf_get_modifiers.s
@@ -0,0 +1,14 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned char cx16_k_kbdbuf_get_modifiers(void);
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-kbdbuf_get_modifiers
+;
+.global cx16_k_kbdbuf_get_modifiers
+cx16_k_kbdbuf_get_modifiers:
+	jsr	__KBDBUF_GET_MODIFIERS
+	ldx	#0
+	rts
diff --git a/mos-platform/cx16/cx16_k_kbdbuf_peek.s b/mos-platform/cx16/cx16_k_kbdbuf_peek.s
new file mode 100644
index 000000000..36bfc6046
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_kbdbuf_peek.s
@@ -0,0 +1,27 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; int cx16_k_kbdbuf_peek(unsigned char *index_ptr); // returns negative if empty, if non-NULL contents of index set to queue length
+; llvm-mos:                             rc2/3
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-kbdbuf_peek
+;
+.global cx16_k_kbdbuf_peek
+cx16_k_kbdbuf_peek:
+	jsr	__KBDBUF_PEEK
+	tay			; save (possible) char
+	lda	__rc2
+	ora	__rc2+1
+	beq	1f		; branch if index_ptr NULL
+	txa
+	sta	(__rc2)		; set *index_ptr to queue len
+1:	txa			; test queue len
+	beq	2f		; branch if queue empty
+	ldx	#0
+	tya			; restore char
+	rts			; return char
+2:	ldx	#$ff		; return -1 for empty
+	txa
+	rts
diff --git a/mos-platform/cx16/cx16_k_kbdbuf_put.s b/mos-platform/cx16/cx16_k_kbdbuf_put.s
new file mode 100644
index 000000000..ec5b54c11
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_kbdbuf_put.s
@@ -0,0 +1,15 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_kbdbuf_put(unsigned char c);
+; llvm-mos:                            A
+; X16 kernal:                          A
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-kbdbuf_put
+;
+.global cx16_k_kbdbuf_put
+cx16_k_kbdbuf_put:
+				; A = c (already set)
+	jmp	__KBDBUF_PUT
diff --git a/mos-platform/cx16/cx16_k_keymap_get_id.s b/mos-platform/cx16/cx16_k_keymap_get_id.s
new file mode 100644
index 000000000..c24c69b02
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_keymap_get_id.s
@@ -0,0 +1,17 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; const char* cx16_k_keymap_get_id(void);
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-keymap
+;
+.global cx16_k_keymap_get_id
+cx16_k_keymap_get_id:
+	sec				; set C for get keymap identifier
+	jsr	__KEYMAP
+	txa
+	sty	__rc2
+	ldx	__rc2
+	rts
diff --git a/mos-platform/cx16/cx16_k_keymap_set.s b/mos-platform/cx16/cx16_k_keymap_set.s
new file mode 100644
index 000000000..f3ad4f68b
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_keymap_set.s
@@ -0,0 +1,20 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned char cx16_k_keymap_set(const char* identifier);	// returns 0 on success
+; llvm-mos:                                   rc2/3
+; X16 kernal:                                 X/Y    C=0
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-keymap
+;
+.global cx16_k_keymap_set
+cx16_k_keymap_set:
+	ldx	__rc2			; X/Y = identifier
+	ldy	__rc3
+	clc				; C = clear for set keymap
+	jsr	__KEYMAP
+	lda	#0			; return 0 on success
+	adc	#0			; return 1 on error (carry set)
+	rts
diff --git a/mos-platform/cx16/cx16_k_macptr.s b/mos-platform/cx16/cx16_k_macptr.s
new file mode 100644
index 000000000..e55d43b5f
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_macptr.s
@@ -0,0 +1,31 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; long cx16_k_macptr(unsigned char count, unsigned char noadvance, void *destaddr); // return negative if not supported
+; llvm-mos:                        A                    X                rc2/3
+; X16 kernal:                      A                    C                X/Y
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-macptr
+;
+.global cx16_k_macptr
+cx16_k_macptr:
+				; A = count
+	cpx	#1		; C = set if noadvance >= 1
+	ldx	__rc2		; X/Y = destaddr
+	ldy	__rc2+1
+	jsr	__MACPTR
+	bcc	noerror
+	lda	#$FF		; -1 on error
+	tax
+	sta	__rc2
+	sta	__rc3
+	rts
+noerror:
+	txa
+	sty	__rc2
+	ldx	__rc2
+	stz	__rc2		; zero extend return
+	stz	__rc3
+	rts
diff --git a/mos-platform/cx16/cx16_k_memory_copy.s b/mos-platform/cx16/cx16_k_memory_copy.s
new file mode 100644
index 000000000..153566cde
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_memory_copy.s
@@ -0,0 +1,19 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_memory_copy(void *source, void *target, unsigned int num_bytes);
+; llvm-mos:                     rc2/3         rc4/5                A/X
+; llvm-mos aliases:             r0            r1                   A/X
+; X16 kernal:                   r0            r1                   r2
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-memory_copy
+;
+.global cx16_k_memory_copy
+cx16_k_memory_copy:
+	sta	__r2		; r2 = num_bytes
+	stx	__r2+1
+				; r1 = target (already set)
+				; r0 = source (already set)
+	jmp	__MEMORY_COPY
diff --git a/mos-platform/cx16/cx16_k_memory_crc.s b/mos-platform/cx16/cx16_k_memory_crc.s
new file mode 100644
index 000000000..131b77b6a
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_memory_crc.s
@@ -0,0 +1,21 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned int cx16_k_memory_crc(void *dataaddr, unsigned int num_bytes);
+; llvm-mos:                      rc2/3                  A/X
+; llvm-mos aliases:              r0                     A/X
+; X16 kernal:                    r0                     r1
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-memory_crc
+;
+.global cx16_k_memory_crc
+cx16_k_memory_crc:
+	sta	__r1		; r1 = num_bytes
+	stx	__r1+1
+				; r0 = dataaddr (already set)
+	jsr	__MEMORY_CRC
+	lda	__r2		; return = __r2
+	ldx	__r2+1
+	rts
diff --git a/mos-platform/cx16/cx16_k_memory_decompress.s b/mos-platform/cx16/cx16_k_memory_decompress.s
new file mode 100644
index 000000000..75fec3f77
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_memory_decompress.s
@@ -0,0 +1,17 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_memory_decompress(void *inaddr, void *outaddr);
+; llvm-mos:                           rc2/3         rc4/5
+; llvm-mos aliases:                   r0            r1
+; X16 kernal:                         r0            r1
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-memory_decompress
+;
+.global cx16_k_memory_decompress
+cx16_k_memory_decompress:
+					; r0 = inaddr (already set)
+					; r1 = outaddr (already set)
+	jmp	__MEMORY_DECOMPRESS
diff --git a/mos-platform/cx16/cx16_k_memory_fill.s b/mos-platform/cx16/cx16_k_memory_fill.s
new file mode 100644
index 000000000..4a30c3034
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_memory_fill.s
@@ -0,0 +1,19 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_memory_fill(void *addr, unsigned int num_bytes, unsigned char value);
+; llvm-mos:                     rc2/3              A/X                      rc4
+; llvm-mos aliases:             r0                 A/X                      r1L
+; llvm-mos:                     r0                 r1                       A
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-memory_fill
+;
+.global cx16_k_memory_fill
+cx16_k_memory_fill:
+				; r0 = addr (already set)
+	sta	__r1		; r1 = num_bytes
+	stx	__r1+1
+	lda	__rc4		; A = value
+	jmp	__MEMORY_FILL
diff --git a/mos-platform/cx16/cx16_k_monitor.s b/mos-platform/cx16/cx16_k_monitor.s
new file mode 100644
index 000000000..9e51dd79e
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_monitor.s
@@ -0,0 +1,12 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_monitor(void) __attribute__((noreturn));
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-monitor
+;
+.global cx16_k_monitor
+cx16_k_monitor:
+	jmp	__MONITOR
diff --git a/mos-platform/cx16/cx16_k_mouse_config.s b/mos-platform/cx16/cx16_k_mouse_config.s
new file mode 100644
index 000000000..104ebaf30
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_mouse_config.s
@@ -0,0 +1,18 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_mouse_config(unsigned char showmouse, unsigned char xsize8, unsigned char ysize8);
+; llvm-mos:                              A                        X                     rc2
+; llvm-mos aliases:                      A                        X                     r0L
+; X16 kernal:                            A                        X                     Y
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-mouse_config
+;
+.global cx16_k_mouse_config
+cx16_k_mouse_config:
+				; A = showmouse (already set)
+				; X = xsize8 (already set)
+	ldy	__rc2		; Y = ysize8
+	jmp	__MOUSE_CONFIG
diff --git a/mos-platform/cx16/cx16_k_mouse_get.s b/mos-platform/cx16/cx16_k_mouse_get.s
new file mode 100644
index 000000000..24b02d37e
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_mouse_get.s
@@ -0,0 +1,24 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; typedef struct { int x, y; } mouse_pos_t;
+; unsigned char cx16_k_mouse_get(mouse_pos_t *mouse_pos_ptr);	// returns mouse button byte
+; llvm-mos:                                   rc2/3
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-mouse_get
+;
+.global cx16_k_mouse_get
+cx16_k_mouse_get:
+	ldx	#__r4		; x = temp pos
+	jsr	__MOUSE_GET
+	tax			; save buttons
+	ldy	#4-1		; copy 4 byte pos to xy_ptr
+1:	lda	__r4,y
+	sta	(__rc2),y
+	dey
+	bpl	1b
+	txa			; return buttons
+	ldx	#0
+	rts
diff --git a/mos-platform/cx16/cx16_k_mouse_scan.s b/mos-platform/cx16/cx16_k_mouse_scan.s
new file mode 100644
index 000000000..cfadfade9
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_mouse_scan.s
@@ -0,0 +1,12 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_mouse_scan(void);
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-mouse_scan
+;
+.global cx16_k_mouse_scan
+cx16_k_mouse_scan:
+	jmp	__MOUSE_SCAN
diff --git a/mos-platform/cx16/cx16_k_savehl.s b/mos-platform/cx16/cx16_k_savehl.s
new file mode 100644
index 000000000..c7bf49d61
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_savehl.s
@@ -0,0 +1,21 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned char cx16_k_savehl(void *startaddr, void *endaddr_plusone); // returns 0 on success
+; llvm-mos:                         rc2/3            rc4/5
+; X16-kernel:                       A                X/Y
+;
+; Not documented on https://github.com/X16Community/x16-docs
+; similar to cbm_k_save, but no two byte header written
+;
+.global cx16_k_savehl
+cbm_k_savehl:
+	ldx	__rc4		; X/Y = end
+	ldy	__rc4+1
+	lda	#__rc2		; A = &startaddr
+	jsr	__SAVEHL
+	bcs	1f		; branch on error
+	lda	#0
+1:	rts
diff --git a/mos-platform/cx16/cx16_k_screen_mode_get.s b/mos-platform/cx16/cx16_k_screen_mode_get.s
new file mode 100644
index 000000000..622fe25dc
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_screen_mode_get.s
@@ -0,0 +1,25 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; typedef struct { unsigned char mode, columns, rows; } screen_mode_info_t;
+; unsigned char cx16_k_screen_mode_get(screen_mode_info_t *info_ptr); // returns 0 on success
+; llvm-mos:                                                rc2/3
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-screen_mode
+;
+.global cx16_k_screen_mode_get
+cx16_k_screen_mode_get:
+	sec			; C = set for get screen mode info
+	jsr	__SCREEN_MODE
+	sty	__r4		; save tile_h
+	ldy	#0
+	sta	(__rc2),y	; store mode
+	iny
+	txa
+	sta	(__rc2),y	; store columns
+	iny
+	lda	__r4
+	sta	(__rc2),y	; store rows
+	rts
diff --git a/mos-platform/cx16/cx16_k_screen_mode_set.s b/mos-platform/cx16/cx16_k_screen_mode_set.s
new file mode 100644
index 000000000..dc5022643
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_screen_mode_set.s
@@ -0,0 +1,19 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned char cx16_k_screen_mode_set(unsigned char mode); // returns 0 on success
+; llvm-mos:                                          A
+; X16 kernal:                                        A
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-screen_mode
+;
+.global cx16_k_screen_mode_set
+cx16_k_screen_mode_set:
+					; A = mode (already set)
+	clc				; clear C for set screen mode
+	jsr	__SCREEN_MODE
+	lda	#0			; return 0 on success
+	adc	#0			; return 1 on error (carry set)
+	rts
diff --git a/mos-platform/cx16/cx16_k_screen_set_charset.s b/mos-platform/cx16/cx16_k_screen_set_charset.s
new file mode 100644
index 000000000..7eaf593ff
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_screen_set_charset.s
@@ -0,0 +1,17 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void cx16_k_screen_set_charset(unsigned char charset_type, void *charsetaddr);
+; llvm-mos:                                    A                   rc2/rc3
+; X16-kernal:                                  A                   X/Y
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-screen_set_charset
+;
+.global cx16_k_screen_set_charset
+cx16_k_screen_set_charset:
+				; A = charset_type (already set)
+	ldx	__rc2		; X/Y = charset_addr
+	ldy	__rc2+1
+	jmp	__SCREEN_SET_CHARSET
diff --git a/mos-platform/cx16/cx16_k_sprite_set_image.s b/mos-platform/cx16/cx16_k_sprite_set_image.s
new file mode 100644
index 000000000..f467642bf
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_sprite_set_image.s
@@ -0,0 +1,34 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+; unsigned char cx16_k_sprite_set_image(unsigned char num, unsigned char w, unsigned char h, unsigned char maskflag, void *imageaddr, void *maskaddr, unsigned char bpp); // returns 0 on success
+; llvm-mos:                                           A                  X              rc2                rc3             rc4/5            rc6/7                   rc8
+; llvm-mos aliases:                                   A                  X              r0L                r0H             r1               r2                      r3L
+; X16 kernal:                                         A                  X              Y                  C               r0               r1                      r2L
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-sprite_set_image
+;
+.global cx16_k_sprite_set_image
+cx16_k_sprite_set_image:
+	ldy	__rc2		; save h in r4 temp
+	sty	__r4
+	ldy	__rc3		; load maskflag
+	cpy	#1		; C = set if maskflag >= 1
+	ldy	__rc4
+	sty	__r0		; r0 = imageaddr
+	ldy	__rc4+1
+	sty	__r0+1
+	ldy	__rc6
+	sty	__r1		; r1 = maskaddr
+	ldy	__rc6+1
+	sty	__r1+1
+	ldy	__rc8
+	sty	__r2		; r2 = bpp
+				; A = num (already set)
+				; X = w (already set)
+	ldy	__r4		; Y = h
+	jsr	__SPRITE_SET_IMAGE
+	lda	#0		; return 0 on success
+	adc	#0		; return 1 on error (carry set)
+	rts
diff --git a/mos-platform/cx16/cx16_k_sprite_set_position.s b/mos-platform/cx16/cx16_k_sprite_set_position.s
new file mode 100644
index 000000000..bd252d16a
--- /dev/null
+++ b/mos-platform/cx16/cx16_k_sprite_set_position.s
@@ -0,0 +1,26 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+; unsigned char cx16_k_sprite_set_position(unsigned char num, unsigned int xpos, unsigned int ypos); // returns 0 on success
+; llvm-mos:                                              A                 X/rc2              rc3/4
+; llvm-mos aliases:                                      A                 r0L/X              r0H/r1L
+; X16 kernal:                                            A                 r0		      r1
+;
+; https://github.com/X16Community/x16-docs/blob/master/X16%20Reference%20-%2004%20-%20KERNAL.md#function-name-sprite_set_position
+;
+.global cx16_k_sprite_set_position
+cx16_k_sprite_set_position:
+	sta	__r4		; save num in r4 temp
+	lda	__rc2
+	ldy	__rc3
+	stx 	__r0		; r0 = xpos
+	sta	__r0+1
+	sty	__r1		; r1 = ypos
+	ldy	__rc3+1
+	sty	__r1+1
+	lda	__r4		; A = num (restored from temp)
+	jsr	__SPRITE_SET_POSITION
+	lda	#0		; return 0 on success
+	adc	#0		; return 1 on error (carry set)
+	rts
diff --git a/mos-platform/cx16/get_numbanks.s b/mos-platform/cx16/get_numbanks.s
new file mode 100644
index 000000000..34f053c1e
--- /dev/null
+++ b/mos-platform/cx16/get_numbanks.s
@@ -0,0 +1,20 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned short get_numbanks(void); // return number of 8K RAM banks at 0xA000-0xBFFF (64=512K up to 256=2MB)
+;
+; Originally from cc65. Modified from original version.  See license information in cx16.h
+; https://github.com/cc65/cc65/blob/master/libsrc/cx16/get_numbanks.s
+;
+.global get_numbanks
+get_numbanks:
+	sec		; set carry to get MEMTOP
+	jsr	__MEMTOP
+	ldx	#0	; assume < 256
+	cmp	#0	; is it 0? (means 256)
+	bne	1f	; branch if not
+	inx		; increment high for 256
+1:	rts
+
diff --git a/mos-platform/cx16/get_ostype.s b/mos-platform/cx16/get_ostype.s
new file mode 100644
index 000000000..9c67acc59
--- /dev/null
+++ b/mos-platform/cx16/get_ostype.s
@@ -0,0 +1,21 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; signed char get_ostype(void);  // return ROM build version (negative pre-release, -1=custom)
+;
+; Originally from cc65. Modified from original version.  See license information in cx16.h
+; https://github.com/cc65/cc65/blob/master/libsrc/cx16/get_ostype.s
+;
+.global get_numbanks
+get_numbanks:
+	ldy	ROM_BANK	; make sure ROM bank 0
+	stz	ROM_BANK
+	ldx	#0		; clear high
+	lda	$FF80		; special ROM build version byte
+	sty	ROM_BANK	; restore previous bank
+	bpl	1f		; branch if version negative
+	dex			; decrement high for sign extend
+1:	rts
+
diff --git a/mos-platform/cx16/get_tv.s b/mos-platform/cx16/get_tv.s
new file mode 100644
index 000000000..252eade12
--- /dev/null
+++ b/mos-platform/cx16/get_tv.s
@@ -0,0 +1,17 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned char get_tv(void);    // return TV_* enum constant for current video signal type
+;
+; Originally from cc65. Modified from original version.  See license information in cx16.h
+; https://github.com/cc65/cc65/blob/master/libsrc/cx16/get_tv.s
+;
+.global get_tv
+get_tv:
+	stz	VERA_CTRL	; set DCSEL=0 to access DC_VIDEO
+	lda	VERA_DC_VIDEO	; load DC_VIDEO
+	and	#$0F		; mask out non-mode bits
+	ldx	#0		; zero extend
+1:	rts
diff --git a/mos-platform/cx16/imag-regs.ld b/mos-platform/cx16/imag-regs.ld
index 86558bd80..2361dc7d1 100644
--- a/mos-platform/cx16/imag-regs.ld
+++ b/mos-platform/cx16/imag-regs.ld
@@ -19,22 +19,27 @@
  * is, __r0 through __r15.
  */
 
-__r0  = 0x0002;
-__r1  = 0x0004;
-__r2  = 0x0006;
-__r3  = 0x0008;
-__r4  = 0x000a;
-__r5  = 0x000c;
-__r6  = 0x000e;
-__r7  = 0x0010;
-__r8  = 0x0012;
-__r9  = 0x0014;
-__r10 = 0x0016;
-__r11 = 0x0018;
-__r12 = 0x001a;
-__r13 = 0x001c;
-__r14 = 0x001e;
-__r15 = 0x0020;
+/* CAUTION: Some X16 kernal calls deviate from this convention!         */
+
+/* X16 kernal reg      X16 convention   LLVM reg alias  LLVM convention */
+__r0  = 0x0002;     /* in/out (args)    __rc2,  __rc3   trash           */
+__r1  = 0x0004;     /* in/out (args)    __rc4,  __rc5   trash           */
+__r2  = 0x0006;     /* in/out (args)    __rc6,  __rc7   trash           */
+__r3  = 0x0008;     /* in/out (args)    __rc8,  __rc9   trash           */
+__r4  = 0x000a;     /* in/out (args)      -      -      (mos-sdk temp)  */
+__r5  = 0x000c;     /* in/out (args)      -      -      (unused)        */
+__r6  = 0x000e;     /* preserve         __rc20, __rc21  preserve        */
+__r7  = 0x0010;     /* preserve         __rc22, __rc23  preserve        */
+__r8  = 0x0012;     /* preserve         __rc24, __rc25  preserve        */
+__r9  = 0x0014;     /* preserve         __rc26, __rc27  preserve        */
+__r10 = 0x0016;     /* preserve         __rc28, __rc29  preserve        */
+__r11 = 0x0018;     /* trash            __rc10, __rc11  trash           */
+__r12 = 0x001a;     /* trash            __rc12, __rc13  trash           */
+__r13 = 0x001c;     /* trash            __rc14, __rc15  trash           */
+__r14 = 0x001e;     /* trash            __rc16, __rc17  trash           */
+__r15 = 0x0020;     /* trash            __rc18, __rc19  trash           */
+/*    = 0x0022                          __rc0,  __rc1   preserve        */
+/*    = 0x0024                          __rc30, __rc31  preserve        */
 
 /* LLVM-MOS caller-saved => X16 callee-saved (arguments; rs1-rs4 => r0-r3).
  * This allows setting arguments in KERNAL wrappers without stashing.
diff --git a/mos-platform/cx16/kernal.S b/mos-platform/cx16/kernal.S
index acd638893..476ac4815 100644
--- a/mos-platform/cx16/kernal.S
+++ b/mos-platform/cx16/kernal.S
@@ -19,6 +19,64 @@
   .global __\name
 .endm
 
+weakdef SAVEHL
+weakdef KBDBUF_PEEK
+weakdef KBDBUF_GET_MODIFIERS
+weakdef KBDBUF_PUT
+weakdef I2C_READ_BYTE
+weakdef I2C_WRITE_BYTE
+weakdef CX_MONITOR
+weakdef ENTROPY_GET
+weakdef KEYMAP
+weakdef CONSOLE_SET_PAGE_MSG
+weakdef CONSOLE_PUT_IMAGE
+weakdef CONSOLE_INIT
+weakdef CONSOLE_PUT_CHAR
+weakdef CONSOLE_GET_CHAR
+weakdef MEMORY_FILL
+weakdef MEMORY_COPY
+weakdef MEMORY_CRC
+weakdef MEMORY_DECOMPRESS
+weakdef SPRITE_SET_IMAGE
+weakdef SPRITE_SET_POSITION
+weakdef FB_INIT
+weakdef FB_GET_INFO
+weakdef FB_SET_PALETTE
+weakdef FB_CURSOR_POSITION
+weakdef FB_CURSOR_NEXT_LINE
+weakdef FB_GET_PIXEL
+weakdef FB_GET_PIXELS
+weakdef FB_SET_PIXEL
+weakdef FB_SET_PIXELS
+weakdef FB_SET_8_PIXELS
+weakdef FB_SET_8_PIXELS_OPAQUE
+weakdef FB_FILL_PIXELS
+weakdef FB_FILTER_PIXELS
+weakdef FB_MOVE_PIXELS
+weakdef GRAPH_INIT
+weakdef GRAPH_CLEAR
+weakdef GRAPH_SET_WINDOW
+weakdef GRAPH_SET_COLORS
+weakdef GRAPH_DRAW_LINE
+weakdef GRAPH_DRAW_RECT
+weakdef GRAPH_MOVE_RECT
+weakdef GRAPH_DRAW_OVAL
+weakdef GRAPH_DRAW_IMAGE
+weakdef GRAPH_SET_FONT
+weakdef GRAPH_GET_CHAR_SIZE
+weakdef GRAPH_PUT_CHAR
+weakdef MACPTR
+weakdef ENTER_BASIC
+weakdef CLOCK_SET_DATE_TIME
+weakdef CLOCK_GET_DATE_TIME
+weakdef JOYSTICK_SCAN
+weakdef JOYSTICK_GET
+weakdef SCREEN_MODE
+weakdef SCREEN_SET_CHARSET
+weakdef MOUSE_CONFIG
+weakdef MOUSE_GET
+weakdef MOUSE_SCAN
+
 weakdef CHKIN
 weakdef CKOUT
 weakdef CHKOUT
diff --git a/mos-platform/cx16/set_tv.s b/mos-platform/cx16/set_tv.s
new file mode 100644
index 000000000..c4779c261
--- /dev/null
+++ b/mos-platform/cx16/set_tv.s
@@ -0,0 +1,19 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void set_tv(unsigned char type);    // set video signal type using TV_* enum constant
+; llvm-mos:                 A
+;
+; Originally from cc65. Modified from original version.  See license information in cx16.h
+; https://github.com/cc65/cc65/blob/master/libsrc/cx16/set_tv.s
+;
+.global set_tv
+set_tv:
+	stz	VERA_CTRL	; set DCSEL=0 to access DC_VIDEO
+	eor	VERA_DC_VIDEO	; eor in current register bits
+	and	#$0F		; don't alter layer or sprite bits
+	eor	VERA_DC_VIDEO	; eor in video mode bits again
+	sta	VERA_DC_VIDEO	; store result with low 4 bits altered
+	rts
diff --git a/mos-platform/cx16/vera_layer_enable.s b/mos-platform/cx16/vera_layer_enable.s
new file mode 100644
index 000000000..e95f7951a
--- /dev/null
+++ b/mos-platform/cx16/vera_layer_enable.s
@@ -0,0 +1,31 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned char vera_layer_enable(unsigned char layers); // enable/disable VERA layers 0/1 (bits 0/1), returns previous
+; llvm-mos:                                     A
+;
+; Originally from cc65. Modified from original version.  See license information in cx16.h
+; https://github.com/cc65/cc65/blob/master/libsrc/cx16/layer_enable.s
+;
+.global vera_layer_enable
+vera_layer_enable:
+        stz     VERA_CTRL              	; set DCSEL=0 to access DC_VIDEO
+        asl
+        asl	                       	; shift new flags into position
+        asl
+        asl
+        ldy     VERA_DC_VIDEO		; save previous value
+        eor     VERA_DC_VIDEO
+        and     #$30
+        eor     VERA_DC_VIDEO      	; Replace old flags with new flags
+        sta     VERA_DC_VIDEO
+        tya
+        and     #$30			; Get old flags
+        lsr
+        lsr
+        lsr
+        lsr
+        ldx     #0			; zero extend
+        rts
diff --git a/mos-platform/cx16/vera_sprites_enable.s b/mos-platform/cx16/vera_sprites_enable.s
new file mode 100644
index 000000000..3417eeb94
--- /dev/null
+++ b/mos-platform/cx16/vera_sprites_enable.s
@@ -0,0 +1,29 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned char vera_sprites_enable(unsigned char enable); // enable/disable VERA sprites (0=off, non-zero=on), returns previous
+; llvm-mos:                                       A
+;
+; Originally from cc65. Modified from original version.  See license information in cx16.h
+; https://github.com/cc65/cc65/blob/master/libsrc/cx16/layer_enable.s
+;
+.global vera_sprites_enable
+vera_sprites_enable:
+        stz     VERA_CTRL              	; set DCSEL=0 to access DC_VIDEO
+        tax                             ; test A
+        beq     1f                      ; branch if zero
+        lda     #$40
+1:      ldy     VERA_DC_VIDEO		; save previous value
+        eor     VERA_DC_VIDEO
+        and     #$40
+        eor     VERA_DC_VIDEO      	; Replace old flags with new flags
+        sta     VERA_DC_VIDEO
+        tya
+        and     #$40			; Get old flags
+        asl                             ; move bit 6 to bit 0 via carry
+        asl
+        rol
+        ldx     #0			; zero extend
+        rts
diff --git a/mos-platform/cx16/videomode.s b/mos-platform/cx16/videomode.s
new file mode 100644
index 000000000..a1942450c
--- /dev/null
+++ b/mos-platform/cx16/videomode.s
@@ -0,0 +1,27 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; signed char videomode(signed char mode);   // set video mode using VIDEOMODE_* enum constant, returns previous or -1 if error
+; llvm-mos:                                      A
+;
+; Originally from cc65. Modified from original version.  See license information in cx16.h
+; https://github.com/cc65/cc65/blob/master/libsrc/cx16/videomode.s
+;
+.global videomode
+videomode:
+        pha                     ; save new mode
+        sec                     ; get old mode
+        jsr     __SCREEN_MODE
+        plx                     ; get new mode in X
+        pha                     ; save old mode
+        txa                     ; get new mode in A
+        clc                     ; set new mode
+        jsr     __SCREEN_MODE
+        pla                     ; get old mode
+        ldx     #0              ; zero extend
+        bcc     1f              ; branch if mode valid
+        dex                     ; -1 for error
+        txa
+1:      rts
diff --git a/mos-platform/cx16/vpeek.s b/mos-platform/cx16/vpeek.s
new file mode 100644
index 000000000..1b38871f7
--- /dev/null
+++ b/mos-platform/cx16/vpeek.s
@@ -0,0 +1,21 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; unsigned char vpeek(unsigned long addr);    // read byte from VERA VRAM address
+; llvm-mos:                     A/X/rc2/3
+;
+; Originally from cc65. Modified from original version.  See license information in cx16.h
+; https://github.com/cc65/cc65/blob/master/libsrc/cx16/vpeek.s
+;
+.global vpeek
+vpeek:
+        stz     VERA_CTRL              	; set DCSEL=0 to access ADDRSEL=0
+        ldy     __rc2
+        sty     VERA_ADDR_H
+        stx     VERA_ADDR_M
+        sta     VERA_ADDR_L
+        ldx     #0
+        lda     VERA_DATA0
+        rts
diff --git a/mos-platform/cx16/vpoke.s b/mos-platform/cx16/vpoke.s
new file mode 100644
index 000000000..f44eeaaf8
--- /dev/null
+++ b/mos-platform/cx16/vpoke.s
@@ -0,0 +1,22 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void vpoke(unsigned char data, unsigned long addr); // write byte value to VERA VRAM address
+; llvm-mos:                A                   X/rc2/3/4
+;
+; Originally from cc65. Modified from original version.  See license information in cx16.h
+; https://github.com/cc65/cc65/blob/master/libsrc/cx16/vpoke.s
+;
+.global vpoke
+vpoke:
+        stz     VERA_CTRL              	; set DCSEL=0 to access ADDRSEL=0
+        ldy     __rc4
+        sty     VERA_ADDR_H
+        ldy     __rc3
+        sty     VERA_ADDR_M
+        ldy     __rc2
+        sty     VERA_ADDR_L
+        sta     VERA_DATA0
+        rts
diff --git a/mos-platform/cx16/waitvsync.s b/mos-platform/cx16/waitvsync.s
new file mode 100644
index 000000000..a1f833eca
--- /dev/null
+++ b/mos-platform/cx16/waitvsync.s
@@ -0,0 +1,18 @@
+.include "imag.inc"
+.include "cx16.inc"
+.text
+
+;
+; void waitvsync(void);  // wait for the vertical blank interrupt
+;
+; Originally from cc65. Modified from original version.  See license information in cx16.h
+; https://github.com/cc65/cc65/blob/master/libsrc/cx16/waitvsync.s
+;
+.global waitvsync
+waitvsync:
+        jsr     __RDTIM
+        sta     __rc2
+1:      jsr     __RDTIM
+        cmp     __rc2
+        beq     1b
+        rts
diff --git a/mos-platform/nes/nes.h b/mos-platform/nes/nes.h
index 4e5866838..a84cd6449 100644
--- a/mos-platform/nes/nes.h
+++ b/mos-platform/nes/nes.h
@@ -3,7 +3,7 @@
 // See https://github.com/llvm-mos/llvm-mos-sdk/blob/main/LICENSE for license
 // information.
 
-// Originally from cc65. Modififed from original version.
+// Originally from cc65. Modified from original version.
 
 /*****************************************************************************/
 /*                                                                           */
diff --git a/utils/sim/mos-sim.c b/utils/sim/mos-sim.c
index 6f19c6f88..9a3824f47 100644
--- a/utils/sim/mos-sim.c
+++ b/utils/sim/mos-sim.c
@@ -66,12 +66,12 @@ int8_t read6502(uint16_t address) {
 
 void finish(void) {
   if (shouldPrintCycles)
-    fprintf(stderr, "%ld cycles\n", clockticks6502);
+    fprintf(stderr, "%llu cycles\n", clockticks6502);
 
   if (shouldProfile)
     for (int addr = 0; addr < 65536; ++addr)
       if (clockTicksAtAddress[addr])
-        fprintf(stderr, "%04x %ld\n", addr, clockTicksAtAddress[addr]);
+        fprintf(stderr, "%04x %llu\n", addr, clockTicksAtAddress[addr]);
 }
 
 void write6502(uint16_t address, uint8_t value) {