Getting correct serial communications between your computer and Megasquirt is critical to enable tuning.
The wireless connection is much more convenient to use. The Bluetooth has a modified firmware and works perfectly.
Bluetooth has a built-in Texas Instruments True RS-232 transceiver converter, with 7 volts of signal amplitude (not 5 volts) with ± 21kV ESD-protected input/output and logic pins.
Cheap transceivers that don't support True RS232 don't work properly... anyone who has tried it knows...
Supports Megasquirt 1 or Megasquirt 2.
Write to me for which megasquirt you need... for mega 1 or for mega 2 they are different