pcmhacking.net

I've probably flashed it well over 100 times iterating this code. Pretty sure all code goes on EEPROM, separate part on board, internal is bootloader. It still shows up as a flash drive if holding boot button when plugged in, but that's it.

Betting a lot of the adaptation from mycropython to Arduino uses a bunch of the same interpitter nonsense. Probably why compiler was less picky than for the Teensy.

Will probably make a revision soon. Initialize pattern history to be 10101010 or 01010101. As is, there's potential for a false match at initial start up in one area of the wheel. When I initially set pattern length to 8, I figured the extra would help and just be simpler. Might later change it to 6 teeth per pattern and initialize 101010 or 010101, for the same 90 degree sync potential GM originally went for.
A logic analyzer/oscilloscope that can record would help show it with pictures and what not, but whatever. Thinking through what the ECU reads on startup... I know it needs done.

Should reset pattern history to initialized values on low RPM cut too. That matters.

I went ahead and made both those changes in 1st post, with 0 testing first.

Considering direction of rotation and the specific pattern used, might not have mattered. Makes sense, designed to work with a very basic ASIC. Need to remember it's short teeth that decode as a 1. The more I mess with this wheel setup, the more I like it. The mechanical logic to it is great.

It's reverted. I need to come up with a repeatable test and test both options. I'll blame it on lack of sleep, not that my reason matters for the end result. Shouldn't have pushed an untested update.

Some sanity checking.
https://chatgpt.com/share/68652bb2-e238 ... 5993269e90
EDIT: I didn't tell it the answer was 5, or 6 including 1st corrupt bit as Delco CIC datasheet says.

AngelMarc wrote: ↑Wed Jul 02, 2025 10:54 pm Some sanity checking.
https://chatgpt.com/share/68652bb2-e238 ... 5993269e90

How reliable, accurate, helpful is the AI support?

lol I added a picture.
I also typed the pattern and looked for partially initialized values that could line up in 2 spots. After failing to notice any, I tried AI; sometimes it blows your mind like it understands perfectly the 1st time and points out some shit you'd never think of, other times you'd swear it has dimentia.When I originally thought there could be a problem, I forgot short teeth equal teeth.