diff --git a/libraries/AP_HAL/board/sitl.h b/libraries/AP_HAL/board/sitl.h
index a20951e0d06ca0..0eae8e932a3c1b 100644
--- a/libraries/AP_HAL/board/sitl.h
+++ b/libraries/AP_HAL/board/sitl.h
@@ -48,6 +48,9 @@
 #define AP_NOTIFY_GPIO_LED_RGB_GREEN_PIN  9
 #define AP_NOTIFY_GPIO_LED_RGB_BLUE_PIN  10
 
+// #define AP_NOTIFY_GPIO_LED_1_ENABLED 1
+#define AP_NOTIFY_GPIO_LED_A_PIN          8  // these are set in SIM_PIN_MASK
+
 #define HAL_HAVE_BOARD_VOLTAGE 1
 #define HAL_HAVE_SERVO_VOLTAGE 1
 #define HAL_HAVE_SAFETY_SWITCH 1
diff --git a/libraries/AP_Notify/AP_Notify.cpp b/libraries/AP_Notify/AP_Notify.cpp
index a74655db832ef3..555331501add04 100644
--- a/libraries/AP_Notify/AP_Notify.cpp
+++ b/libraries/AP_Notify/AP_Notify.cpp
@@ -20,6 +20,7 @@
 #include "Buzzer.h"
 #include "Display.h"
 #include "ExternalLED.h"
+#include "GPIO_LED_1.h"
 #include "IS31FL3195.h"
 #include "PCA9685LED_I2C.h"
 #include "NavigatorLED.h"
@@ -313,6 +314,9 @@ void AP_Notify::add_backends(void)
                 ADD_BACKEND(NEW_NOTHROW AP_BoardLED());
 #elif AP_NOTIFY_GPIO_LED_2_ENABLED
                 ADD_BACKEND(NEW_NOTHROW AP_BoardLED2());
+#endif
+#if AP_NOTIFY_GPIO_LED_1_ENABLED
+                ADD_BACKEND(NEW_NOTHROW GPIO_LED_1());
 #endif
                 break;
 #if AP_NOTIFY_TOSHIBALED_ENABLED
diff --git a/libraries/AP_Notify/AP_Notify_config.h b/libraries/AP_Notify/AP_Notify_config.h
index 62238d28ed09e0..de72773bb4924d 100644
--- a/libraries/AP_Notify/AP_Notify_config.h
+++ b/libraries/AP_Notify/AP_Notify_config.h
@@ -47,6 +47,10 @@
 #define AP_NOTIFY_GPIO_LED_2_ENABLED 0
 #endif
 
+#ifndef AP_NOTIFY_GPIO_LED_1_ENABLED
+#define AP_NOTIFY_GPIO_LED_1_ENABLED 0
+#endif
+
 #ifndef AP_NOTIFY_GPIO_LED_RGB_ENABLED
 #define AP_NOTIFY_GPIO_LED_RGB_ENABLED 0
 #endif
diff --git a/libraries/AP_Notify/GPIO_LED_1.cpp b/libraries/AP_Notify/GPIO_LED_1.cpp
new file mode 100644
index 00000000000000..950a1ce49cad2f
--- /dev/null
+++ b/libraries/AP_Notify/GPIO_LED_1.cpp
@@ -0,0 +1,77 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "AP_Notify_config.h"
+
+#if AP_NOTIFY_GPIO_LED_1_ENABLED
+
+#include "GPIO_LED_1.h"
+
+#include <AP_HAL/HAL.h>
+#include "AP_Notify.h"
+
+#ifndef AP_NOTIFY_GPIO_LED_A_PIN
+#error "define AP_NOTIFY_GPIO_LED_A_PIN"
+#endif
+
+extern const AP_HAL::HAL& hal;
+
+bool GPIO_LED_1::init(void)
+{
+    // when HAL_GPIO_LED_ON is 0 then we must not use pinMode()
+    // as it could remove the OPENDRAIN attribute on the pin
+#if HAL_GPIO_LED_ON != 0
+    hal.gpio->pinMode(AP_NOTIFY_GPIO_LED_A_PIN, HAL_GPIO_OUTPUT);
+#endif
+    hal.gpio->write(AP_NOTIFY_GPIO_LED_A_PIN, HAL_GPIO_LED_OFF);
+    return true;
+}
+
+/*
+  main update function called at 50Hz
+ */
+void GPIO_LED_1::update(void)
+{
+    uint32_t new_pattern;
+    if (AP_Notify::flags.initialising) {
+        new_pattern = INITIALIZING;
+    } else if (AP_Notify::flags.armed) {
+        new_pattern = ARMED;
+    } else if (AP_Notify::flags.pre_arm_check) {
+        new_pattern = READY_TO_ARM;
+    } else {
+        new_pattern = NOT_READY_TO_ARM;
+    }
+    if (new_pattern != current_pattern) {
+        next_bit = 0;
+        current_pattern = new_pattern;
+        last_timestep_ms = 0;
+    }
+
+    const uint32_t now_ms = AP_HAL::millis();
+    if (now_ms - last_timestep_ms < 100) {
+        return;
+    }
+    last_timestep_ms = now_ms;
+
+    const auto new_state = (current_pattern & (1U<<next_bit)) ? HAL_GPIO_LED_ON : HAL_GPIO_LED_OFF;
+    hal.gpio->write(AP_NOTIFY_GPIO_LED_A_PIN, new_state);
+    next_bit++;
+    if (next_bit > 31) {
+        next_bit = 0;
+    }
+}
+
+#endif  // AP_NOTIFY_GPIO_LED_1_ENABLED
diff --git a/libraries/AP_Notify/GPIO_LED_1.h b/libraries/AP_Notify/GPIO_LED_1.h
new file mode 100644
index 00000000000000..129e6cac520185
--- /dev/null
+++ b/libraries/AP_Notify/GPIO_LED_1.h
@@ -0,0 +1,48 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include "AP_Notify_config.h"
+
+#if AP_NOTIFY_GPIO_LED_1_ENABLED
+
+#include <AP_Common/AP_Common.h>
+#include <AP_HAL/AP_HAL_Boards.h>
+
+#include "NotifyDevice.h"
+
+class GPIO_LED_1 : public NotifyDevice
+{
+public:
+    // initialise the LED driver
+    bool init(void) override;
+
+    // should be called at 50Hz
+    void update(void) override;
+
+private:
+
+    // left-to-right, each bit represents 100ms
+    static const uint32_t INITIALIZING = 0b10101010101010101010101010101010UL;
+    static const uint32_t NOT_READY_TO_ARM = 0b11111111000000001111111100000000UL;
+    static const uint32_t READY_TO_ARM = 0b11111111111111100000000000000000UL;
+    static const uint32_t ARMED = 0b11111111111111111111111111111111UL;
+
+    uint32_t current_pattern = INITIALIZING;
+    uint32_t last_timestep_ms;
+    uint8_t next_bit;
+};
+
+#endif  // AP_NOTIFY_GPIO_LED_1_ENABLED
diff --git a/libraries/SITL/SIM_Aircraft.cpp b/libraries/SITL/SIM_Aircraft.cpp
index 366ec909304ace..a6baf91eb9da24 100644
--- a/libraries/SITL/SIM_Aircraft.cpp
+++ b/libraries/SITL/SIM_Aircraft.cpp
@@ -1094,6 +1094,9 @@ void Aircraft::update_external_payload(const struct sitl_input &input)
     }
 #endif
 
+#if AP_SIM_GPIO_LED_1_ENABLED
+    sim_led1.update(*this);
+#endif
 #if AP_SIM_GPIO_LED_2_ENABLED
     sim_led2.update(*this);
 #endif
diff --git a/libraries/SITL/SIM_Aircraft.h b/libraries/SITL/SIM_Aircraft.h
index 4af43bb80cd092..90f07089ea60b1 100644
--- a/libraries/SITL/SIM_Aircraft.h
+++ b/libraries/SITL/SIM_Aircraft.h
@@ -38,6 +38,7 @@
 #include <Filter/Filter.h>
 #include "SIM_JSON_Master.h"
 #include "ServoModel.h"
+#include "SIM_GPIO_LED_1.h"
 #include "SIM_GPIO_LED_2.h"
 #include "SIM_GPIO_LED_3.h"
 #include "SIM_GPIO_LED_RGB.h"
@@ -377,6 +378,9 @@ class Aircraft {
 #endif
 
 
+#if AP_SIM_GPIO_LED_1_ENABLED
+    GPIO_LED_1 sim_led1{8};  // pin to match sitl.h
+#endif
 #if AP_SIM_GPIO_LED_2_ENABLED
     GPIO_LED_2 sim_led2{13, 14};  // pins to match sitl.h
 #endif
diff --git a/libraries/SITL/SIM_GPIO_LED_1.cpp b/libraries/SITL/SIM_GPIO_LED_1.cpp
new file mode 100644
index 00000000000000..5ae8a40ef4d3da
--- /dev/null
+++ b/libraries/SITL/SIM_GPIO_LED_1.cpp
@@ -0,0 +1,31 @@
+#include "SIM_config.h"
+
+#if AP_SIM_GPIO_LED_1_ENABLED
+
+#include "SIM_GPIO_LED_1.h"
+
+#include <SITL/SITL.h>
+
+using namespace SITL;
+
+void GPIO_LED_1::init()
+{
+    leds.init();
+}
+
+void GPIO_LED_1::update(const class Aircraft &aircraft)
+{
+    if (!init_done) {
+        init();
+        init_done = true;
+    }
+
+    const uint16_t pin_mask = AP::sitl()->pin_mask.get();
+    const bool new_led_states[1] {
+        ((pin_mask & uint16_t((1U<<LED_A_PIN))) != 0),
+    };
+
+    leds.set_state(new_led_states);
+}
+
+#endif
diff --git a/libraries/SITL/SIM_GPIO_LED_1.h b/libraries/SITL/SIM_GPIO_LED_1.h
new file mode 100644
index 00000000000000..44094993276fb2
--- /dev/null
+++ b/libraries/SITL/SIM_GPIO_LED_1.h
@@ -0,0 +1,46 @@
+/*
+
+  Simulator for GPIO-based "Board LEDs"
+
+  ./Tools/autotest/sim_vehicle.py -v ArduCopter --gdb --debug --rgbled
+
+  reboot
+
+ */
+
+
+#include "SIM_config.h"
+
+#if AP_SIM_GPIO_LED_1_ENABLED
+
+#include "SIM_LED_n.h"
+
+namespace SITL {
+
+class GPIO_LED_1
+{
+public:
+
+    GPIO_LED_1(uint8_t _LED_A_PIN) :
+        LED_A_PIN{_LED_A_PIN}
+        { }
+
+    void update(const class Aircraft &aircraft);
+
+private:
+
+    void init();
+    bool init_done;
+
+    SIM_LED_n<1>::LEDColour colours[1] {
+        SIM_LED_n<1>::LEDColour::RED,
+    };
+
+    SIM_LED_n<1> leds{"GPIO_LED_1", colours};
+
+    uint8_t LED_A_PIN;
+};
+
+} // namespace SITL
+
+#endif  // AP_SIM_GPIO_LED_2_ENABLED
diff --git a/libraries/SITL/SIM_LED_n.cpp b/libraries/SITL/SIM_LED_n.cpp
index 30cd3b90efde9c..df721612f79275 100644
--- a/libraries/SITL/SIM_LED_n.cpp
+++ b/libraries/SITL/SIM_LED_n.cpp
@@ -90,6 +90,7 @@ void SIM_LED_n<NUM_LEDS>::init()
     pthread_create(&thread, NULL, update_thread_start, this);
 }
 
+template class SIM_LED_n<1>;
 template class SIM_LED_n<2>;
 template class SIM_LED_n<3>;
 
diff --git a/libraries/SITL/SIM_config.h b/libraries/SITL/SIM_config.h
index 99a53bfb0fd437..bd5d07e799c50f 100644
--- a/libraries/SITL/SIM_config.h
+++ b/libraries/SITL/SIM_config.h
@@ -27,6 +27,10 @@
 #define AP_SIM_LED_N_ENABLED (CONFIG_HAL_BOARD == HAL_BOARD_SITL) && defined(WITH_SITL_RGBLED)
 #endif
 
+#ifndef AP_SIM_GPIO_LED_1_ENABLED
+#define AP_SIM_GPIO_LED_1_ENABLED AP_SIM_LED_N_ENABLED && 0
+#endif
+
 #ifndef AP_SIM_GPIO_LED_2_ENABLED
 #define AP_SIM_GPIO_LED_2_ENABLED AP_SIM_LED_N_ENABLED && 0
 #endif
@@ -36,7 +40,7 @@
 #endif
 
 #ifndef AP_SIM_GPIO_LED_RGB_ENABLED
-#define AP_SIM_GPIO_LED_RGB_ENABLED AP_SIM_LED_N_ENABLED
+#define AP_SIM_GPIO_LED_RGB_ENABLED AP_SIM_LED_N_ENABLED && 0
 #endif
 
 #ifndef AP_SIM_LOWEHEISER_ENABLED