It 's about an Arduino project connected to an ELM-327 OBDII Bluetooth through a HC-05 bluetooth module.
The HC-05 is connected to Arduino with serial UART, and is configured (with AT commands) as Master to connect to ELM-327 OBDII Bluetooth which is the slave.
As soon as connection established begins the initialitation (with AT commands) of ELM-327.
After that we can read Engine RPM from car's ECU.
Next just display the RPM to 7-segment LEDS.
Shift Lights going ON at the RPM that we configure pressing the button at desired Engine RPM, value is stored to EEPROM.
Please feel free to comment or suggest or contact me.
Code needs some comments, i hope i can post soon, schematics will post as soon as possible.