how should I set an description for 2902 based code`/

[JopWerff]

Hi h2zero,

I have a bit a problem getting things done with 2902 based stuff. I tried self several ways - researched a little - had a look to this keyboard stuff of sivar2311. But I didn't get it. I'm a real newbie in the area of BLE.

I searched also for examples in the NewBLE-library but nothing to find what is a bit alike what I want to do.

Can you help me?

Here my code to convert to using NimBLED from using the original BLE Library:

NimBLECharacteristic* pCharacteristicTEMP = pBmeService->createCharacteristic(TEMP_UUID, NIMBLE_PROPERTY::NOTIFY);

BLEDescriptor* pBLEDescriptorTEMP = pCharacteristicTEMP->createDescriptor(BLEUUID((uint16_t)0x2902));
pBLEDescriptorTEMP->setValue("BME temperature Celsius");
pCharacteristicTEMP->addDescriptor(pBLEDescriptorTEMP);

These last 3 lines: how I have to implement this in the NimBLE-way?

Jop

[h2zero]

In this library the 2902 is automatic when the characteristic has the notification property. You need to delete those 3 lines.

[JopWerff]

Not quite clear to me. How the descriptor will get its content in this "2902-automatic" way?

Here my more complete code that makes difference between Celsius and Fahrenheit, dependent of a compiler directive.

  // Create NimBLE Characteristics and Create a NimBLE Descriptor
  // Temperature
  #ifdef temperatureCelsius
    pCharacteristicTEMP = pBmeService->createCharacteristic(TEMP_UUID, NIMBLE_PROPERTY::NOTIFY);

    NimBLEDescriptor* pNimBLEDescriptorTEMP = pCharacteristicTEMP->createDescriptor(BLEUUID((uint16_t)0x2902));
    pNimBLEDescriptorTEMP->setValue("BME temperature Celsius");
    pCharacteristicTEMP->addDescriptor(pNimBLEDescriptorTEMP);
    
  #else
    pCharacteristicTEMP = pBmeService->createCharacteristic(TEMP_UUID, NIMBLE_PROPERTY::NOTIFY);

    NimBLEDescriptor* pNimBLEDescriptorTEMP = pCharacteristicTEMP->createDescriptor(BLEUUID((uint16_t)0x2902));   
    pNimBLEDescriptorTEMP->setValue("BME temperature Fahrenheit");
    pCharacteristicTEMP->addDescriptor(pNimBLEDescriptorTEMP);
  #endif  

How I have to implement this in NimBLE making a distinguish between these temperature scales?

Regards,
Jop

[h2zero]

That's is not what the 2902 descriptor is for, it's only for setting the client notification subscription status.

You'll want to use some other method to achieve what you are doing here.