ecg: handle error when writing to BLE fails

preload/apps/ecg/__init__.py

@@ -177,13 +177,18 @@ class ECG:
 
     def callback_ecg(self, datasets):
         if self.ble_streaming:
-            self.ble_sample_count += len(datasets)
+            try:
                 self.b.gatts_notify(
                     1,
                     self.ecg_data_handle,
                     struct.pack(">h", self.ble_sample_count & 0xFFFF)
                     + struct.pack(">" + ("h" * len(datasets)), *datasets),
                 )
+            except OSError:
+                pass
+
+            # We count all samples, even if we failed to send them
+            self.ble_sample_count += len(datasets)
 
             # Don't update the screen if it should be off during a connection
             if not config.get_option("BLE Disp"):