again: BleWinrtDll.cpp:501 SubscribeCharacteristicAsync catch: The attribute cannot be written.

[zhouyexi98]

Hello:
I was able to use the computer's Bluetooth LE Explorer tool to connect to my device and debug it. When I was running Blewinrtdell in unity I was able to search the device to find services and characteristics, but when I clicked subscribe I got the error warning above. Can you kindly give me some advice?

[zhouyexi98]

I find the reason why I can't debug. Every time I write a value, I only write the content to the characteristic 1,but I need to write the value to the characteristics 3. How can I solve this problem?

[adabru]

Hi @zhouyexi98,
for investigation, you can download and run the Microsoft's Bluetooth Low Energy sample and see whether subscribing works there. If the demo works, it should be fixable in this repo.

[arafi123]

Hi @adabru

I tested the Microsoft BLE sample and saw the data coming there for few characteristic but here I get for the same characteristic the same error that "the attribute cannot be written ". Could you please look into that ?

Thanks

[adabru]

Hi @arafi123,
do I understand you correctly: There is a characteristic that is consistently read from the Microsoft BLE sample without error but shows the error BleWinrtDll.cpp:501 SubscribeCharacteristicAsync catch: The attribute cannot be written everytime you try to subscribe to that characteristic from the BleWinrtDll demo scene?

[arafi123]

Hi @adabru Yes you have understood it correctly.

[adabru]

The relevant line should be

BleWinrtDll/BleWinrtDll/BleWinrtDll.cpp

Line 486 in f2635b7

auto status = co_await characteristic.WriteClientCharacteristicConfigurationDescriptorAsync(GattClientCharacteristicConfigurationDescriptorValue::Notify);

You can compare it to the code in the Microsoft sample.