C++, Arduino: HC-05 on digital 8,9

ADMDestroyer · January 28, 2021

Does anyone know how can i connect the HC-05 bluetooth module to my arduino without using TX and RX ? I had some problems with uploading on the board while the module was connected...i needed to disconnect it if i wanted to update my code..this is a problem since it is very hard to get to it. Could someone reply with a simple led on/off software that uses digital pins for the module ?

trag1c · January 29, 2021

There is a couple options that you can try.

Some MCU's support more than 1 hardware UART. You would need to look at board specs or possibly the datasheet for the MCU.

Or you can use software serial. Its not as fast as hardware UART but depending on your application it shouldn't be a problem. It uses standard DIO pins that are pulsed on and off by software according to the data being sent. The only requirement on the pin is that it is interrupt capable.

https://www.arduino.cc/en/Reference/softwareSerial