PCM THOUGHT PROCESS please explain

[wadesns]

I have been attempting to learn how to tune for some time now and it seems like a lot of my questions are, "How does it work?" So now i am asking for some guidance. I would like to know the though process of the pcm. There are a few things that i already know just from working on cars, like the baro comes from the map reading when the ignition switch is in the KOEO position. What other readings are computed in similar ways. Also seems like one pid runs another in some cases. A break down from start to finish would be awesome :) or if the info can be posted maybe i can put the data together to make a table of some sort for refrence.

Thanks,
..RJ..

[SOMhaveit]

I have read this and I think it is pretty informative.

http://carprogrammer.com/Z28/PCM/LS1/Holden_LS1.pdf

[wadesns]

I have read through this and it is very informative but not exactly what i am looking for. Anyone else have any info?

[TAQuickness]

Check this thread out (http://www.forum.efilive.com/showthread.php?t=6975).

[2002_z28_six_speed]

Almost sounds like he wants a flowchart of the GM Os's...

How variables are really created. What is used in one OS and not another. Stuff like that.

[wadesns]

Yes that is probably more of what i am trying to say but doesn't have to be for all OS mainly just the general idea.

[5.7ute]

I started to write something up for myself but it turned into too huge an exercise. The table descriptions in the tune tool give good information on what other tables are influenced & will be a good starting point.