Handle recovery blanking as separate state, update docs, format code

README.md

@@ -18,17 +18,18 @@ To flash MCU:
 7) wait for program to flash, check messages in terminal for errors
 
 Current features:
-- response time: 100ms - changes in conditions faster than this won't be detected
+- response time: 100ms - changes in conditions faster than this won't be detected, limit to max 500ms
 - startup delay: 60s - the relay will not trip is PS_ON is disconnected (or 0) and power has just been applied
 - power off delay: 20s - time to allow the board/PC to shutdown cleanly
-- recovery delay: 5s - recover with PS_ON after power off, blanking time to avoid fast power off/on cycle
+- recovery delay: 30s - blanking time to avoid fast power off/on cycle, after which relay can recover with PS_ON (self-reset)
 
 Leds show state:
 - green off and red off - no power to the relay
 - green on and red on -  MCU is reset or in programming mode
 - green on and red blinking - startup delay, power to system, only SC is available
 - green on and red off - power to the system
 - green blinking and red off - PS_ON triggered, power off delay
+- green and red blinking - no power to the system, wait for recovery delay
 - green off and red on - no power to the system, relay is in power off state
 - green alternate red blinking - SC triggered
 

src/main.c

@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <STC15Fxx.h>
 #include <delay.h>
+#include <reset.h>
 
 #define LED_OFF     P30     /* Power off led (red) */
 #define LED_ON      P31     /* Power on led (green) */
@@ -11,13 +12,9 @@
 #define RESPONSE_DELAY  100 /* how fast the sofware responds to input changes */
 #define START_DELAY_S   60  /* time at startup to ignore PS_DLY state */
 #define STOP_DELAY_S    20  /* time to wait before power off after trigger by PS_DLY */
-#define RECOVER_DELAY_S 5   /* time to wait before power recovery after PS_DLY gets restored */
+#define RECOVER_DELAY_S 30  /* time to wait before power recovery after PS_DLY gets restored */
 #define BLINKER_MUL     3   /* used for blinking LEDs, multiple of RESPONSE_DELAY */      
 
-#if (RECOVER_DELAY_S > (STOP_DELAY_S-1))
-#error "RECOVER_DELAY_S must be at least 1 second smaller than STOP_DELAY_S"
-#endif
-
 #if (RESPONSE_DELAY > 500)
 #error "RESPONSE_DELAY must be lower than 500ms"
 #endif
@@ -30,18 +27,38 @@
 #define PWDN_DLY_TICKS  (STOP_DELAY_S*1000UL/RESPONSE_DELAY*1UL)
 #define PWRE_DLY_TICKS  (STOP_DELAY_S*1000UL/RESPONSE_DELAY*1UL)
 
-/* stated of the device */
-typedef enum
-{
+/* states of the device */
+typedef enum {
     powerup,    /* first startup/reset will ignore PS_DLY state */
     running,    /* normal running state */
     psdelay,    /* PS_DLY was triggered, but we wait for power off delay */
+    blanking,   /* PS_DLY was triggered, power was cut, we wait recovery delay*/
     tripped,    /* PS_DLY trigger occurred */
     tripped_sc, /* SCP trigger occurred */
 }states_t;
 
-void main(void)
-{
+/* vars */
+states_t state = powerup;
+uint32_t updelay = 0;
+uint8_t blink = 0;
+
+/* things to always do when switching to new state */
+void goto_state(states_t new) {
+    /* reset leds */
+    LED_ON = 0;
+    LED_OFF = 0;
+    /* if short, start with red led on */
+    if (new == tripped_sc)
+        LED_OFF = 1;
+    /* reset timers */
+    updelay = 0;
+    blink = 0;
+    /* set new state */
+    state = new;
+}
+
+/* setup and init i/o */
+void init_io(void) {
     /* setup i/o */
     P3M1 = 0xB4;
     P3M0 = 0xB4;
@@ -50,10 +67,11 @@ void main(void)
     RELAY = 0;
     LED_OFF = 0;
     LED_ON = 0;
-    /* vars */
-    states_t state = powerup;
-    uint32_t updelay = 0;
-    uint8_t blink = 0;
+}
+
+void main(void) {
+    /* setup i/o */
+    init_io();
     /* program loop */
     while(1) {
         /* wait response time */
@@ -62,103 +80,110 @@ void main(void)
         if (SCP)
             state = tripped_sc;
         /* check states */
-        switch (state)
-        {
+        switch (state) {
         case powerup:
             /* powering state */
             RELAY = 0;
+            /* led state */
+            LED_ON = 1;
             /* increase delay timers */
             updelay += 1;
             blink += 1;
+            /* blink led */
             if (blink > BLINKER_MUL) {
                 /* leds */
                 LED_OFF = (!LED_OFF);
-                LED_ON = 1;
                 blink = 0;
             }
             /* check power up delay */
             if (updelay > PWUP_DLY_TICKS) {
-                updelay = 0;
                 /* check PS_DLY */
                 if (PS_DLY)
-                    state = running;
-                else
-                    state = tripped;
+                    goto_state(running);
+                /* PS_ON must have signal to continue ! */
+                goto_state(blanking);
             }
             break;
         case running:
             /* powering state */
             RELAY = 0;
-            /* leds */
+            /* led state */
             LED_OFF = 0;
             LED_ON = 1;
             /* reset timers */
             updelay = 0;
             blink = 0;
             /* check PS_DLY */
             if (PS_DLY)
-                state = psdelay;
+                goto_state(psdelay);
             break;        
         case psdelay:
             /* powering state */
             RELAY = 0;
+            /* led state */
+            LED_OFF = 0;
             /* increase delay timers */
             updelay += 1;
             blink += 1;
+            /* blink led */
             if (blink > BLINKER_MUL) {
                 /* leds */
-                LED_OFF = 0;
                 LED_ON = (!LED_ON);
                 blink = 0;
             }
             /* check power down delay */
-            if (updelay > PWDN_DLY_TICKS) {
-                /* reset timers */
+            if (updelay > PWDN_DLY_TICKS)
+                goto_state(blanking);
+            break;        
+        case blanking:
+            /* tripped state */
+            RELAY = 1;
+            /* increase delay timers */
+            updelay += 1;
+            blink += 1;
+            /* blink both leds */
+            if (blink > BLINKER_MUL) {
+                /* leds */
+                LED_OFF = (!LED_OFF);
+                LED_ON = (!LED_ON);
                 blink = 0;
-                updelay = 0;
-                state = tripped;
             }
+            /* check power down delay */
+            if (updelay > PWRE_DLY_TICKS)
+                goto_state(tripped);
             break;
         case tripped:
             /* tripped state */
             RELAY = 1;
             /* leds */
             LED_OFF = 1;
             LED_ON = 0;
-            /* increase delay timers */
-            updelay += 1;
-            /* power recovery */
-            if (updelay > PWRE_DLY_TICKS) {
-                /* check PS_DLY pin */
-                if (!PS_DLY) {
-                    /* reset timers */
-                    blink = 0;
-                    updelay = 0;
-                    state = running;
-                }
-                updelay = PWRE_DLY_TICKS;
-            }
+            /* power recovery (self-reset) */
+            if (!PS_DLY)
+                //goto_state(powerup);
+                reset();
             break;   
         default:
             /* tripped state */
             RELAY = 1;
             /* increase delay timers */
             blink += 1;
-            /* blinking leds alternatively, one it BLINKER_MUL on, then the other is BLINKER_MUL on */
-            if (blink > (2*BLINKER_MUL))
-                blink=0;
+            /* blinking leds alternating them */
             if (blink > BLINKER_MUL) {
                 /* leds */
-                LED_OFF = 1;
-                LED_ON = 0;
-            } else {
-                /* leds */
-                LED_OFF = 0;
-                LED_ON = 1;
+                if(LED_ON) {
+                    LED_OFF = 1;
+                    LED_ON = 0;
+                } else {
+                    LED_OFF = 0;
+                    LED_ON = 1;
+                }
+                /* reset blink timer */
+                blink = 0;
             }
-            /* reset timers */
+            /* reset other timers */
             updelay = 0;
             break;
-        }       
+        }
     }
 }