feat: ✨ Added new bootloader "bootgatthrm" which exposes HRM data via BLE

apps/bootgatthrm/boot.js

@@ -1,8 +1,9 @@
 (() => {
   function setupHRMAdvertising() {
     /*
-     * This function preparse BLE heart rate Advertisement.
+     * This function prepares BLE heart rate Advertisement.
      */
+
     NRF.setServices({
       0x180D: { // heart_rate
         0x2A37: { // heart_rate_measurement
@@ -10,34 +11,44 @@
           value: [0x06, 0],
         }
       }
-    }, { advertise: ['180D'] });
+    }, { advertise: [0x180d] });
 
   }
-
   function updateBLEHeartRate(hrm) {
     /*
      * Send updated heart rate measurement via BLE
      */
-    if (hrm === undefined) return;
+    if (hrm === undefined || hrm.confidence < 50) return;
     try {
       NRF.updateServices({
-        '180d': {
-          '2a37': {
+        0x180D: {
+          0x2A37: {
             value: [
               0x06, //
-              hrm
+              hrm.bpm
             ],
             notify: true
           }
         }
       });
     } catch (error) {
-      // After setupHRMAdvertising() BLE needs to restart.
-      // We force a disconnect if the Bangle was connected while setting HRM
-      NRF.disconnect();
+      if (error.message.includes("BLE restart")) {
+        /*
+         * BLE has to restart after service setup.  
+         */
+        NRF.disconnect();
+      }
+      else if (error.message.includes("UUID 0x2a37")) {
+        /*
+         * Setup service if it wasn't setup correctly for some reason 
+         */
+        setupHRMAdvertising();
+      } else {
+        console.log("[bootgatthrm]: Unexpected error occured while updating HRM over BLE! Error: " + error.message);
+      }
     }
   }
 
   setupHRMAdvertising();
-  Bangle.on("HRM", function (hrm) { updateBLEHeartRate(hrm.bpm); });
+  Bangle.on("HRM", function (hrm) { updateBLEHeartRate(hrm); });
 })();