Bluetooth UART (BTM-222)
PCB for the BTM-222 and 5V level converters
Here's the Layout of a BTM-222 Bluetooth PCB, following the Roboternetz Guidelines Mini Format. The circuit comes from Robotfreak, but is basically the minimal circuit described in the datasheet (370kB) (361 KiB).
|R2||5k Ohm Poti||Conrad|
|R3 - R10||1k Ohm||-|
|Q1 - Q4||BC547 NPN||Conrad|
|IC2||BTM 222||Ulrich Radig|
|LED 1+2||LED 5mm||-|
Soldering the standard parts should be no problem. You should use a find soldering iron to connect each pin of the BTM-222, one after another. A 31mm long piece of wire can be used as antenna.
Interfacing the BTM-222
Before using the BTM-222 you have to configure it. You can change the speed, data format, name, PIN and some other things. You have to connect the hardware serial interface of the BTM-222 to a PC and issue the AT-Commands documented in the datasheet. It is very important to use only '\r' as Line-End-Character. Using '\n' or "\r\n" will result in error messages from the module.