Notify fix (#7)

* use notify isntead of updateCharacteristicValue

* typo

* auto-start service

BluetoothMIDIService.cpp

@@ -35,10 +35,10 @@ const uint8_t midiServiceUuid[] = {
 
 BluetoothMIDIService::BluetoothMIDIService(BLEDevice *dev): ble(*dev) {
     timestamp = 0;
-    memset(midi, 0, sizeof(midi));
+    memset(midiBuffer, 0, sizeof(midiBuffer));
     firstRead = true;
 
-    GattCharacteristic midiCharacteristic(midiCharacteristicUuid, midi, 0, sizeof(midi), 
+    GattCharacteristic midiCharacteristic(midiCharacteristicUuid, midiBuffer, 0, sizeof(midiBuffer), 
           GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ
         | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY
         );
@@ -64,7 +64,7 @@ void BluetoothMIDIService::onDataRead(const GattReadCallbackParams* params)
     {
         if (firstRead) {
             // send empty payload upon first connect
-            ble.updateCharacteristicValue(midiCharacteristicHandle, midi, 0);        
+            ble.gattServer().notify(midiCharacteristicHandle, (uint8_t *)midiBuffer, 0);
             firstRead = false;
         }
     }
@@ -82,35 +82,35 @@ bool BluetoothMIDIService::connected() {
 void BluetoothMIDIService::sendMidiMessage(uint8_t data0) {
     if (connected()) {
         unsigned int ticks = tick.read_ms() & 0x1fff;
-        midi[0] = 0x80 | ((ticks >> 7) & 0x3f);
-        midi[1] = 0x80 | (ticks & 0x7f);
-        midi[2] = data0;
+        midiBuffer[0] = 0x80 | ((ticks >> 7) & 0x3f);
+        midiBuffer[1] = 0x80 | (ticks & 0x7f);
+        midiBuffer[2] = data0;
         
-        ble.updateCharacteristicValue(midiCharacteristicHandle, midi, 3);
+        ble.gattServer().notify(midiCharacteristicHandle, (uint8_t *)midiBuffer, 3);
     }
 }
 
 void BluetoothMIDIService::sendMidiMessage(uint8_t data0, uint8_t data1) {
     if (connected()) {
         unsigned int ticks = tick.read_ms() & 0x1fff;
-        midi[0] = 0x80 | ((ticks >> 7) & 0x3f);
-        midi[1] = 0x80 | (ticks & 0x7f);
-        midi[2] = data0;
-        midi[3] = data1;
+        midiBuffer[0] = 0x80 | ((ticks >> 7) & 0x3f);
+        midiBuffer[1] = 0x80 | (ticks & 0x7f);
+        midiBuffer[2] = data0;
+        midiBuffer[3] = data1;
         
-        ble.updateCharacteristicValue(midiCharacteristicHandle, midi, 4);
+        ble.gattServer().notify(midiCharacteristicHandle, (uint8_t *)midiBuffer, 4);
     }
 }
 
 void BluetoothMIDIService::sendMidiMessage(uint8_t data0, uint8_t data1, uint8_t data2) {
     if (connected()) {
         unsigned int ticks = tick.read_ms() & 0x1fff;
-        midi[0] = 0x80 | ((ticks >> 7) & 0x3f);
-        midi[1] = 0x80 | (ticks & 0x7f);
-        midi[2] = data0;
-        midi[3] = data1;
-        midi[4] = data2;
+        midiBuffer[0] = 0x80 | ((ticks >> 7) & 0x3f);
+        midiBuffer[1] = 0x80 | (ticks & 0x7f);
+        midiBuffer[2] = data0;
+        midiBuffer[3] = data1;
+        midiBuffer[4] = data2;
         
-        ble.updateCharacteristicValue(midiCharacteristicHandle, midi, 5);
+        ble.gattServer().notify(midiCharacteristicHandle, (uint8_t *)midiBuffer, 5);
     }
 }

BluetoothMIDIService.h

@@ -47,7 +47,7 @@ private:
     void onDisconnection(const Gap::DisconnectionCallbackParams_t* params);
 
     uint16_t timestamp;
-    uint8_t midi[5];
+    uint8_t midiBuffer[5];
     bool firstRead;
 
     BLEDevice &ble;

README.md

@@ -15,21 +15,20 @@ For another device like a smartphone to use any of the Bluetooth "services" whic
 
 This package allows the @boardname@ to act as a MIDI peripherical, like a piano. It requires to connect to a BLE MIDI device to receive the commands and play them.
 
-Place a ``||bluetooth start midi service||`` block in your program to enable MDI over Bluetooth low energy.
-
-```blocks
-bluetooth.startMidiService();
-```
-
 This library uses the [MIDI package](/pkg/microsoft/pxt-midi). 
-Please refer to that project documentation for further details.
+Please refer to that project documentation for further details on using MIDI commands.
 
 ## Supported Platforms
 
 This package is currently only supported on iOS (iPad/iPhone). 
 Any app that supports a MIDI keyboard or instrument should work.
 
-* iPhone/iPad: [Apple GarageBand](https://itunes.apple.com/us/app/garageband/id408709785?mt=8)
+### Apple GarageBand
+
+* [iPhone/iPad App]](https://itunes.apple.com/us/app/garageband/id408709785?mt=8)
+
+Go to settings (gearwheel), click **Advanced**, click **Bluetooth MIDI device** and connect to the @boardname@.
+If the @boardname@ is marked as offline, click **Edit** and **Forget** the device.
 
 ## Supported targets
 

bluetooth.ts

@@ -4,12 +4,13 @@ namespace bluetooth {
      */
     //% blockId=bluetooth_start_midi block="bluetooth start midi service"
     //% part=bluetooth
+    //% blockHidden=1 deprecated=true
     export function startMidiService() {
         function send(buffer: Buffer) {
             bluetooth.midiSendMessage(buffer);
         }
         midi.setTransport(send);
-        bluetooth.midiSendMessage(pins.createBuffer(0));
+        bluetooth.midiSendMessage(pins.createBuffer(0)); // does nothing but starts service lazily
     }
 
     /**
@@ -20,4 +21,7 @@ namespace bluetooth {
     export function midiSendMessage(data: Buffer) {
         return;
     }
-}
+
+}
+// automatically start midi service
+bluetooth.startMidiService();

tests.ts

@@ -4,7 +4,9 @@ bluetooth.onBluetoothConnected(() => {
 bluetooth.onBluetoothDisconnected(() => {
     basic.showString("D")
 })
-bluetooth.startMidiService();
+
+// this is automatic
+// bluetooth.startMidiService();
 
 basic.showString("S")
 input.onButtonPressed(Button.A, () => {