Okay, I've tested the USB-TTL adaptor. I have now a level converter between the ACIA and the USB adaptor. There is still no communication. The USB adaptor has RTS and CTS lines, should I try to connect them to the ACIA, too?

The bluetooth module stores all settings, I make.

Thanks for your answers!

I connected only Rx and Tx, nothing else. Should I connect the RTS/CTS lines, too? They seem to be on the module on Pin 3 and 4. I assume, that they are 3.3V level, too.
Is a voltage divider okay, or should I use some IC for that?

The key pin is needed for AT command, I've ...

Hi Daryl,

I have the same module, as seen here:

http://www.instructables.com/id/AT-comm ... th-module/

So, it's not only the module, but it's on a breakout board. I tried to configure the module with AT-commands with an USB-TTL adaptor. This works.

Cheers,
Michael

Hi everybody,

I'm trying to connect a bluetooth module to a 6551 ACIA, but maybe I think, that it's too simple :D

I am using a HC-05 bluetooth module, that should be able to connect to a UART TTL source, but it does not seem to work. I tried to connect Rx to Tx and vice versa. Has anybody tried ...