rusEFI firmware currently supports two protocols for ECU monitoring & control

1. human-readable native protocol - connect to the ECU using HyperTerminal. This used to be protocol rusEFI console was using but not any more, we are moving towards not having text protocol enabled by default.

   List of commands

   Java console code overview

2. binary protocol for integration with rusEFI console or TunerStudio tuning software See tunerstudio.cpp for a brief description of this binary protocol

For physical level rs232 is used ("serial port") - either via a FL232 chip or by emulating a USB device right within stm32f4. A bluetooth option is also available.

Forum thread

Q: Why two protocols? can you achieve the same results using both protocols? A: Not really. Our text-based protocol has support for human-readable messages and it handles our own build-in logic analyzer - it is better for troubleshooting. The protocol has better support for engine tuning in terms of editing individual cells on fuel maps etc.

Q: Is the binary protocol compatible with MegaSquirt? A: Kind of, but not really. The general protocol is the same, but the packet format is rusEFI specific. All this works based on TunerStudio packet definition flexibility.