Writing "" to a Characteristic?

[vicatcu]

I have a characteristic that is a string. If I use nRF Connect and Write value as text, and leave the New value field empty and Send, I get feedback from my write event handler for the characteristic receives a non-blank string:

Serial.print("Characteristic Written: ");
const char * str = pCharacteristic->getValue().c_str();
Serial.println(str);

The value received by the callback happens to be a string that has length 1 and contains just the first letter of the previously initialized value of the characteristic. This seems like new behavior / a bug to me. What do you think?

Incidentally, that's the same result I get from my own app instead of nRF connect, which uses the @capacitor-community/bluetooth-le plugin and does this:

      import { BleClient, RequestBleDeviceOptions, numbersToDataView } from '@capacitor-community/bluetooth-le';
      ...
      // value is a string to be sent
      const bytes: number[] = value.split('').map(v => v.charCodeAt(0));
      const dv = numbersToDataView(bytes);
      await BleClient.write(deviceId, _service, _characteristic, dv, {timeout});

... to be clear, this used to work just fine.

[vicatcu]

My workaround is to change my app to append a null terminator explicitly:

      import { BleClient, RequestBleDeviceOptions, numbersToDataView } from '@capacitor-community/bluetooth-le';
      ...
      // value is a string to be sent
      const bytes: number[] = value.split('').map(v => v.charCodeAt(0));
      bytes.push(0x00); // ADDED THIS LINE
      const dv = numbersToDataView(bytes);
      await BleClient.write(deviceId, _service, _characteristic, dv, {timeout});

[h2zero]

Thanks @vicatcu, I will test this and see what's happening.