I got some trouble with one of the HC-05 Bluetooth modules.
I am using a Pro Mini 3.3V 8MHz.
For some first testing I put a software serial example sketch onto the Pro Mini.
I connected D10/D11 with the serial I/O pins of the HC-05 and GND to GND and
Vcc to 3.3Vin.
The HC-05 starts blinking in a hurry.
I took my Android tablet and switch on Bluetooth.
The module shows up as "HC-05" and I selected it to pair with it.
A dialog pops up, asking me fot the password "1234".
This was accepted (I checked with a wrong one, which was rejected at once)
and the LEDs of the HC-05 start blinking slowing.
Then it falls back to hastily blinking and my tablet says "Cannot communicate with HC-05".
Pairing wasn't done.
A Bluetooth terminal Android app also states after trying to pair "Bad MAC addr.".
This has worked before...
I have no clue what happened here.
What can I do to revive this Bluetooth module?
Any help is very appreciated - thank you very much in advance!