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Where can I find the serial number info in my obdii gm pcm?
Also how hard would it be to alter crank resolution in the pcm programming or can it even be done?
I'm not real good at the programming level stuff,hoping someone can enlighten me.
I think if I knew the address location for the info I could check it out furthur in the .bin .
I'm sure that info is in the SAE papers but I can't find access to them either.
If it is specific to a certain pcm then i'll say for a 12200411.
Is it just not feasible to alter say an LS1 file to read a 7x crank signal?
Or is it so coded into the other programming that it would literally mean a complete rewrite like i'm thinking?
(In other words,start with a suitable pcm with a matching .bin)
If dumb questions or i'm thinking sideways please set me straight. I've been using TCII for 7ish yrs but I know more about the cars than the programming side itself.
I learned how it all worked with TCII,alot of reading and obdII training. While I have passable knowledge there are large gaps in how the programming functions :)
In the TunerPro XDF there is a Scaler for Degrees from Low Res CKP pulse to cylinder TDC which is in degrees, not sure if that helps on the craqnk signal issue?
that will account for signal "lead"(example being that a 60V6 ICM signals the 3X circuit 60* before the next piston goes to TDC, 3800 ICM is i THINK 70* before the next TDC), but it won't adjust the number of pulses to interpret engine speed or position correctly.
That was what I figured.
Common sense tells me there is either a constant or algorithim/calculation in the PCM that would need altered.
However,I don't know enough to find it.
I do have some ideas to narrow it down,but it will take time. Was hoping someone had a definitive answer.
For later reminder,maybe this TPU is where I need to look to alter the crank or cam resolution?
http://www.thirdgen.org/techboard/di...-101-step.html
Quote:
At the heart of the PCM is the 68332 processor. This processor is geared towards automotive and robotics control. This means that there are some additional commands included such as the boxed table look up commands, and the math co-processor present in other 68XXX MPUs is instead replaced by the TPU, or timing processing unit. This is a somewhat nebuluous piece of internal hardware that you wont have direct access to in the code. Its main purpose is to independantly process timing based events such as the MAF frequency input, crank position reference pulses, etc. with the intent of reducing the load on the main processor. It has its own 'microcode' that it executes to interface with the hardware and read in the various inputs. The places where you will see it is mainly when the PCM handles timer updates and periodic input reads like the crank reference pulses and outputs, such as the injector pulsewidths for each cylinder