Strange behaviour with BLE and HM-10


I’m experiencing an issue when trying to read the custom characteristic of an HM-10 bluetooth module with the BLE Component. Here are a few precisions:

  • Writing data works as expected
  • I can read and write data with the BLE Scanner app (haven’t try others)
  • When writing with Thunkable or read/writing with BLE Scanner, everything works as expected with my serial monitor on Arduino Nano.
  • The error flag of the Receive function does not fire. Instead, it seems the function is just returning “empty” data.
  • An error is triggered when trying to receive a Byte Array instead of String.
  • I can without problem read data from another characteristic (for example Device Name). It displays the string as expected.

Here are the blocks I am using. I have tried several things but I couldn’t make it work.

This works and Reception_Label changes according to the name of the Device Name characteristic

This doesn’t work. Reception_Label remains empty (it is changing as it is not empty at first).

This triggers the following error : “n is not a function. (In ‘n(void 0,v.t0.message)’, ‘n’ is undefined)”

The blocks in charge of connecting to the device seem to work properly as I can Transmit data, and Receive data from another characteristic.

Also, the characteristic is set for Read, Write, Notify and others, as I can read/write without problem with BLE Scanner.

I have also tried different TYPE configuration (0,1,2,3) for the HM-10 without any success. Apart from this, I am using almost all the factory settings.

Does anybody have experienced this issue before ? I’ve seem other people having trouble with the BLE component and HM-10 but never this particular problem. Most of them would receive incoherent data but all of them receive at least something.

Thank you for your help.

After further investigation, here is an aven weirder behaviour. When I Transmit data, it works (I get it on my Arduino’s Serial monitor. However, the function Transmit does not seem to return anything.

For example, with the following code, Send_Label does not update at all (remains as initialized) and no vibration is trigerred at all.


Again, the data is received by the HM-10 and is transferred to Arduino Nano via Serial.

Any idea of what’s happening here ?

Was this ever solved? I wasn’t able to figure it out either.

I believe is has something todo with the Data format or notification/indication characteristic.