Posted on May 17, 2011 at 14:33I assume you intend to use one of the Bluegiga modules that runs their iWrap software to provide full Bluetooth functionality. (This excludes Bluegiga WT21 which needs you to provide the higher layers of the bluetooth protocol stack. You can interface WT21 to a system that has those higher layers e.g. something running linux.)
It is not very difficult to talk to Bluegiga bluetooth modules using their iWrap command language over a serial port. You should wire up the hardware handshaking lines CTS and RTS as well as TXD and RXD. You need to wire them up as a ''null modem'' i.e. link CTS on the stm32 to RTS on the Bluegiga module.
I also like to be able to reset the Bluegiga module, so I wire its reset pin to a convenient GPIO pin on the stm32. I suggest you wire up another couple of GPIO pins on the stm32 to convenient PIO pins on the Bluegiga module so that you can distinguish between commands and data in each direction (DTR and CD).
The default baud rate is 115200, although this can be changed.
Have you got as far as having problems, or are you just trying to find out about ''gotcha's'' before you make your first prototype. My first prototype was a standard stm32 demo board wired to a ''three-dimensional sculpture'' of a bluegiga WT12 module on a piece of veroboard. But it all worked as intended. I then added the DTR and CD lines.
Note: WT12 != WT21
