Well ordered the first circuit boards for prototype 4.
WTF cost was USD10 shipped for 10 custom boards.
It is insane what you can fit into a tiny space.
The board is 20x76mm and max 5mm high with all these features:
now 1cm longer and added reverse polarity protection. Plus no need to replace diodes for 24v vehicles.
fuse, self resetting
short-circuit aka reverse polarity protection
12/24v switch mode power supply for low heat 90% efficiency
Just need to swap the fuse for use in 24v vehicles
Optional ign switch input to power up
Electrical power noise filtering
Electrical filtering ADC pins
Spare 5v and 3v3 volt outputs
4x static (ESD)protection for buttons and knobs etc
12 general purpose input/outputs
Current generation CAN 2.0 controller with listen real listen only mode.
CAN bus noise filtering, ESD and voltage spike (TVS) protection
optional canbus termination for aftermarket ecu 2nd bus use.
ESP32 module with dual core cpu, wifi and Bluetooth
connector for firmware update and Arduino IDE supported
This is massive overkill and parts are high spec low tolerance ones.
board can run as almost anything, supports full LCD displays etc.
Adding web configuration for colour of each led and rpm it triggers at, mostly done.
You can set can ID and bytes via web to look at so supports most cars and aftermarket ecus.
Also want to add an aftermarket mode that allows ecu to do some cool things that I have seen any other product do.