From 011f212056274ec5431376432befed9b85e70abc Mon Sep 17 00:00:00 2001
From: sl-firmware <sl-firmware@saltylab.local>
Date: Sat, 28 Feb 2026 17:43:25 -0500
Subject: [PATCH] fix: Status LEDs solid=OK blink=error (#22)
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New LED behavior (active-low, PC15=LED1, PC14=LED2):
  Disarmed, IMU OK : LED1 solid ON  + LED2 off
  Armed            : LED1 solid ON  + LED2 solid ON
  Tilt fault       : LED1 blink 1Hz + LED2 blink 1Hz
  IMU error        : LED1 blink 1Hz + LED2 solid ON

Rule: solid = good, slow blink (~1Hz) = needs attention.
Removed the confusing fast-blink-at-5Hz-for-error and the
baro-flash-every-5s patterns.

status_update() signature changed: baro_ok → armed + tilt_fault
so the LED pattern can reflect arm state directly.

Closes #22.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 include/status.h | 14 +++++++++++++-
 src/main.c       |  4 +++-
 src/status.c     | 39 +++++++++++++++++++--------------------
 3 files changed, 35 insertions(+), 22 deletions(-)

diff --git a/include/status.h b/include/status.h
index 9badbb6..6519b1a 100644
--- a/include/status.h
+++ b/include/status.h
@@ -3,5 +3,17 @@
 #include <stdint.h>
 void status_init(void);
 void status_boot_beep(void);
-void status_update(uint32_t tick, int imu_ok, int baro_ok);
+/*
+ * status_update() — call every main loop iteration.
+ * Controls LED1 (PC15) and LED2 (PC14), both active-low.
+ *
+ *  Solid ON  = good (normal operation)
+ *  Slow blink (~1 Hz) = needs attention (error or fault)
+ *
+ *  LED1 solid + LED2 off  → disarmed, IMU OK
+ *  LED1 solid + LED2 solid → armed
+ *  Both slow blink         → tilt fault
+ *  LED1 slow blink + LED2 solid → IMU error (solid LED2 = always-on indicator)
+ */
+void status_update(uint32_t tick, int imu_ok, int armed, int tilt_fault);
 #endif
diff --git a/src/main.c b/src/main.c
index 38e0ba1..be4f77c 100644
--- a/src/main.c
+++ b/src/main.c
@@ -232,7 +232,9 @@ int main(void) {
             CDC_Transmit((uint8_t *)buf, len);
         }
 
-        status_update(now, (imu_ret == 0), (bal.state == BALANCE_ARMED));
+        status_update(now, (imu_ret == 0),
+                      (bal.state == BALANCE_ARMED),
+                      (bal.state == BALANCE_TILT_FAULT));
         HAL_Delay(1);
     }
 }
diff --git a/src/status.c b/src/status.c
index 58dd31b..4045220 100644
--- a/src/status.c
+++ b/src/status.c
@@ -42,26 +42,25 @@ void status_boot_beep(void) {
     HAL_GPIO_WritePin(BEEPER_PORT, BEEPER_PIN, GPIO_PIN_RESET);
 }
 
-void status_update(uint32_t tick, int imu_ok, int baro_ok) {
-    if (imu_ok) {
-        /* Slow blink LED1 at 1Hz */
-        if ((tick / 500) % 2)
-            HAL_GPIO_WritePin(LED1_PORT, LED1_PIN, GPIO_PIN_RESET); /* ON */
-        else
-            HAL_GPIO_WritePin(LED1_PORT, LED1_PIN, GPIO_PIN_SET);   /* OFF */
-
-        /* LED2: quick flash every 5s if baro OK */
-        if (baro_ok && (tick % 5000) < 100)
-            HAL_GPIO_WritePin(LED2_PORT, LED2_PIN, GPIO_PIN_RESET);
-        else
-            HAL_GPIO_WritePin(LED2_PORT, LED2_PIN, GPIO_PIN_SET);
-    } else {
-        /* Fast blink LED1 at 5Hz = error */
-        if ((tick / 100) % 2)
-            HAL_GPIO_WritePin(LED1_PORT, LED1_PIN, GPIO_PIN_RESET);
-        else
-            HAL_GPIO_WritePin(LED1_PORT, LED1_PIN, GPIO_PIN_SET);
-        /* LED2 solid ON */
+void status_update(uint32_t tick, int imu_ok, int armed, int tilt_fault) {
+    /* Solid = good, blink = needs attention (1 Hz, 500ms half-period) */
+    GPIO_PinState blink = ((tick / 500) % 2) ? GPIO_PIN_RESET  /* ON half */
+                                              : GPIO_PIN_SET;   /* OFF half */
+    if (!imu_ok) {
+        /* IMU error: LED1 blinking (attention), LED2 solid ON */
+        HAL_GPIO_WritePin(LED1_PORT, LED1_PIN, blink);
         HAL_GPIO_WritePin(LED2_PORT, LED2_PIN, GPIO_PIN_RESET);
+    } else if (tilt_fault) {
+        /* Tilt fault: both LEDs slow blink */
+        HAL_GPIO_WritePin(LED1_PORT, LED1_PIN, blink);
+        HAL_GPIO_WritePin(LED2_PORT, LED2_PIN, blink);
+    } else if (armed) {
+        /* Armed: both LEDs solid ON */
+        HAL_GPIO_WritePin(LED1_PORT, LED1_PIN, GPIO_PIN_RESET);
+        HAL_GPIO_WritePin(LED2_PORT, LED2_PIN, GPIO_PIN_RESET);
+    } else {
+        /* Normal disarmed: LED1 solid ON, LED2 off */
+        HAL_GPIO_WritePin(LED1_PORT, LED1_PIN, GPIO_PIN_RESET);
+        HAL_GPIO_WritePin(LED2_PORT, LED2_PIN, GPIO_PIN_SET);
     }
 }