I'm looking to alert a connected device over Bluetooth when an accelerometer detects motion. I'm thinking of using the HM-10 Bluetooth module and an ATtiny for controlling the accelerometer.
The doc says that AT-commands can only be sent via UART. Does that mean the ATTiny will need to have an UART port? Could an ATtiny45 be used instead?
Thanks
Best Answer
The module does require you to use the UART protocol in order to use it. It is possible to emulate a UART signal via bit banging, but this requires more from the MCU in order to make it work. AVR304 describes the most efficient way to do this.
Fortunately, the USI found in most tinyAVR devices, including the ATtinyX5, can be used as part of a half-duplex UART connection, alleviating some of the load. This is covered in AVR307.