Nordik UART app with Multiple service reception

[Shrikant]

I need to receive both UART Service data and HRS service data on the app.

Currently I have seen on Nordik Connect app , both the services can be found and can connect and receive data.

I need to do same with my app using nordik UART App code.

I have changed UART profile to HRS profile and code was working, i was receiving Nordik HRS service data.

But i want both services should be used and receives data. so i have prepare separate UARTService_HRS for hrs profile in the same code.also added needed changed.but it gives error null pointer exception on BLEGattService.

Please help

[Shrikant]

but with same features it giving problem to iOS UART App. when both receiver characteristics notification is on, then transmission is very slow sometimes takes 2 seconds sometimes 10 seconds. doesn't understand how to handle this with ios

[Hung Bui]

Adding delay isn't a very good solution. You can try: after you write to one service, you wait for the call back before you write to the second one.

[Shrikant]

but my current problem is when 2 characteristics from different services i have started notification on, my transmission on transmission characteristics goes on toss. can you help me understand how to get over it.

I am developing App for iPhone UART service App.

I have two services. Nordik UART Service and HRM service

When I notify receiver characteristics of both services,my transmission characteristics taking delay of 2 to 10 seconds to transmit data.

when i notify only single receiver characteristics, transmission works fine.but i start notify second receiver characteristics, transmission delayed.

Please go through my below code for reception and transmission. How do i manage multiple services with multiple characteristics, i could not allow to have transmission delay.

//Service Discovery Code:

+ (CBUUID *) uartServiceUUID
{
    return [CBUUID UUIDWithString:@"6e400001-b5a3-f393-e0a9-e50e24dcca9e"];
}
+ (CBUUID *) txCharacteristicUUID
{
    return [CBUUID UUIDWithString:@"6e400002-b5a3-f393-e0a9-e50e24dcca9e"];
}
+ (CBUUID *) rxCharacteristicUUID
{
    return [CBUUID UUIDWithString:@"6e400003-b5a3-f393-e0a9-e50e24dcca9e"];
}
+ (CBUUID *) torqueInformationServiceUUID
{
    return [CBUUID UUIDWithString:@"0000180D-0000-1000-8000-00805f9b34fb"];
}
+ (CBUUID *) torquerxCharacteristicUUID
{
    return [CBUUID UUIDWithString:@"00002A37-0000-1000-8000-00805f9b34fb"];
}
- (UARTPeripheral *) initWithPeripheral:(CBPeripheral*)peripheral delegate:(id<UARTPeripheralDelegate>) delegate
{
    if (self = [super init])
    {
        _peripheral = peripheral;
        _peripheral.delegate = self;
        _delegate = delegate;
//        myperipheral=peripheral;
    }
    return self;
}
- (void) didConnect
{
[_peripheral discoverServices:@[self.class.uartServiceUUID,self.class.torqueInformationServiceUUID]];
    NSLog(@"Did start service discovery.");    
}

- (void) didTSConnect
{
      NSLog(@" discovery start ,,,.........");  
}
- (void) peripheral:(CBPeripheral )peripheral didDiscoverServices:(NSError)error
{
    if (error)
    {
        NSLog(@"Error discovering services: %@", error)        
        return;
    }
    for (CBService *service in peripheral.services)
    {
        NSLog(@"Discovered service: %@", service.UUID);
        [peripheral discoverCharacteristics:nil forService:service];
    } 
     NSLog(@"Discovered service: %@", tsservice.UUID);
  }
- (void) peripheral:(CBPeripheral )peripheral didDiscoverCharacteristicsForService:(CBService )service error:(NSError *)error
{
   if (error)
    {
        NSLog(@"Error discovering characteristics: %@", error);
        receptionStartFlag=false;
        return;  
    }
    for (CBCharacteristic *d in service.characteristics)
        {   
          if ([service.UUID isEqual:self.class.uartServiceUUID])
            {
                if ([d.UUID isEqual:self.class.rxCharacteristicUUID])
                {
                    NSLog(@"Found RX characteristic");
                    self.rxCharacteristic = d;                
                    rxChar=_rxCharacteristic;                
                    [self.peripheral setNotifyValue:YES forCharacteristic:d];
                    [self.peripheral readValueForCharacteristic:d];                
                }
                else   if ([d.UUID isEqual:self.class.txCharacteristicUUID])
                {
                    NSLog(@"Found TX characteristic");
                    self.txCharacteristic = d;
                    txChar=_txCharacteristic;
                    [self.peripheral setNotifyValue:YES forCharacteristic:d];
                }
            }   
        }
        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH,0),                     ^{
    for (CBCharacteristic *d in service.characteristics)
      {
       if ([service.UUID isEqual:self.class.torqueInformationServiceUUID])
         {
            if ([d.UUID isEqual:self.class.torquerxCharacteristicUUID])
               {
                   NSLog(@"Found  TSRX characteristic");
                   self.rxCharacteristic = d;
                   rxChar=rxCharacteristic;
                  [self.peripheral setNotifyValue:YES forCharacteristic:d];
                  [self.peripheral readValueForCharacteristic:d];
               }
                                          
           }
         }
        });
    
}

- (void) peripheral:(CBPeripheral )peripheral didUpdateValueForCharacteristic:
(CBCharacteristic )characteristic error:(NSError *)error
   {
    if (error)
      {
        NSLog(@"Error receiving notification for characteristic %@: %@", 
        characteristic, error);
        return;
      }
    
    //actual reception 
    NSData *dataRec=self.rxCharacteristic.value;
    
    Byte byteData[[dataRec length]];//(Byte*)malloc(len);
    
    [dataRec getBytes:&byteData];
}

//**Transmission Code**

int8_t bytes2[] ={128,00,00,00,00,00,00,00,00,00,00,00,00};
            NSData *data2 = [NSData dataWithBytes:bytes2 length:sizeof(bytes2)];
            
            if ((txChar.properties & CBCharacteristicPropertyWrite) != 0)
            {
                [myperipheral writeValue:data2 forCharacteristic:txChar
                                    type:CBCharacteristicWriteWithResponse];
            }
            else if ((txChar.properties & CBCharacteristicPropertyWrite) != 0)
            {
                [myperipheral writeValue:data2 forCharacteristic:txChar 
                 type:CBCharacteristicWriteWithResponse];
            }
            else
            {
                NSLog(@"No write property on TX characteristic, %lu.", (unsigned 
                long)txChar.properties);
            }

[Hung Bui]

If you don't have a sniffer trace, I can't help you on this case. You should also print a log in your peripheral. The log should print out when it receive the notification enabling (CCCD writing) and when it start sending each notification.