Eculocate

Read data from the K-line of a Honda motorbike ECU and publish it using UDP over Wifi.

Comprises:

• some code for an ESP32-C3 wich can be connected (via level shifters and other electronics, don't plug it straight in) to the bike's ECU,

• a very PoC implementation of an android client, using Termux

Building

The repo is split into two crates in a cargo workspace: code in ecu-portable can be built and run using the native compiler, hence is unit-testable, and code in ecu-esp32 depends on all the esp32 gubbins so you can test it only by running it.

    cargo test -p ecu-portable --target x86_64-unknown-linux-gnu
	SSID=my-wifi PASSWORD="my-wifi-password" cargo run --release

How it works

The ESP32 is connected to the diagnostic port of the ECU and can interrogate it to dump its "tables". This is based on "K-line", a 1 wire 10400 baud serial connection operating with 12V logic.

It connects to a wifi network (wifi credentials are presently hardcoded) and listens on a UDP socket for incoming subscription requests. When it receives a subscription request, it starts to periodically query the ECU for the requested tables and sends the value using UDP back to the subscriber.

To avoid using hardcoded IP addresses, it uses multicast DNS/DNS service discovery to advertise itself as providing the `_keihin._udp.local" service, so a client can use zeroconf/bonjour/avahi to find where it is.

For the moment, there is no security on the UDP service. Until and unless that canges, you probably shouldn't tell it to connect to untrusted wifi networks.

There is a prototype/example client in android-termux-client/. Consult the README in that directory for details.