Respiratory frequency check (cc #61)

src/core/main_task.c

@@ -29,6 +29,10 @@
 
 volatile GlobalState_t globalState;
 
+// Used to measure the actual respiratory frequency
+static uint32_t lastCycleCount;
+static TickType_t startBPMCheckTime;
+
 static const char *globalStateDescr[] = {
     "welcome",
     "welcome_wait_cal",
@@ -39,6 +43,8 @@ static const char *globalStateDescr[] = {
 };
 
 static void setGlobalState(GlobalState_t newState, bool notifyMotor, bool populateDisplay);
+static void resetBPMCheck();
+static void checkBPM();
 
 void initMainTask()
 {
@@ -109,6 +115,8 @@ void MainTask(void *pvParameters)
                 upd_params(buttons_pressed);
                 if (BUTTON_PRESSED(buttons_pressed, button_startstop)) {
                     setGlobalState(run, true, false);
+                    // Reset actual BPM measurement when moving from stop to run
+                    resetBPMCheck();
                 }
 
                 break;
@@ -118,6 +126,8 @@ void MainTask(void *pvParameters)
                     setGlobalState(stop, true, false);
                 }
 
+                checkBPM();
+
                break;
             case critical_failure:
                 break;
@@ -174,6 +184,25 @@ static void setGlobalState( GlobalState_t newState,
     }
 }
 
+static void resetBPMCheck() {
+    DEBUG_PRINT("Reset BPMCheck");
+    lastCycleCount = cycleCount;
+    startBPMCheckTime = xTaskGetTickCount();
+}
+
+static void checkBPM() {
+    TickType_t elapsedTime = xTaskGetTickCount() - startBPMCheckTime;
+    if (elapsedTime > pdMS_TO_TICKS(BPM_CHECK_PERIOD_MS)) {
+        uint8_t measuredBPM = ((uint8_t) (cycleCount - lastCycleCount)) / BPM_CHECK_PERIOD_PER_MIN;
+        DEBUG_PRINT("Measured BPM: %u", measuredBPM);
+        if (ABS(((int8_t) measuredBPM) - ((int8_t) bpm)) > BPM_TOL) {
+            sendNewAlarm(abnFreq);
+        }
+
+        resetBPMCheck();
+    }
+}
+
 // TODO: move, nothing to do here
 void check_volume(uint32_t actual_vol) {
     // Convert target tidal volume to tens µl

src/core/main_task.h

@@ -16,6 +16,10 @@
 
 #define ALARM_AUTO_UNMUTE_DELAY 120 * 1000L
 
+#define BPM_CHECK_PERIOD_MS 60 * 1000L
+#define BPM_CHECK_PERIOD_PER_MIN 1
+#define BPM_TOL 2
+
 // MAIN wake-up notification
 #define MAIN_NOTIF_ALARM 0x01
 

src/core/motor_control.c

@@ -112,8 +112,7 @@ static TickType_t boundedWaitTime;
 static bool waitTimeoutAllowed;
 static int32_t cycle_volume;
 
-static uint32_t cycleCount;
-
+volatile uint32_t cycleCount;
 
 #if DEBUG_MOTOR
 static const char *state_names[] = {

src/core/motor_control.h

@@ -109,6 +109,8 @@ extern volatile BreathState_t breathState;
  */
 extern volatile MotorErrorState_t motorErrorState;
 
+extern volatile uint32_t cycleCount;
+
 /** @init_motor Initialize the motor state machine
  */
 void init_motor();