the flash PROM is a fairly common Intel unit(AB28F400B). supposedly, at some point in time AMD units were used and they are 1MB instead of 512KB(AT28F800B)
I think we must have wildly differing definitions of "fairly common." The real problem in my mind is still getting a replacement chip. Show me a 'add to cart' page from a reputable company (newark/digikey). I've yet to find suitable chips for sale, and I refuse to pull the factory chip off a 0411 PCB without a replacement in hand.

Flashing through the OBD-II serial pin or even BDM header is where it's at for us, though I have not yet been able to find the requisite technical information to make it happen. The OBD process is simple: upload program code into RAM (to download the updated calibration data), but I'd much prefer to start from a jumping off point if work has already been attempted (by who??). Durahax claimed he was able to use BDM to pull a .bin from a 0411, but he never posted the details. Not sure if he succeeded with his diesel PCM yet. Also not sure if he was able to write to the flash chip using BDM (would explain why he hasn't posted a detailed success story). He's close to me, I intend to contact him... (I drove through philly yesterday, HEH).

If any of you boys are holding technical infoz, I'd invest some time to make DIY 0411 a reality with beer-ware. I have a 4.8 in the barn with THREE 0411's, and my L31-tbi has a warped head leaking into the cylinders... =(. I will probably end up pulling another L31 soon ($200 + intake gaskets), but only because I'm lacking requisite technical information to h4x0r my 0411's.

I've seen claims that AVT hardware has been used to read+flash a GM PCM, but I REALLY want to see some source code or technical info that would enable me to write the code for 0411 before I blindly buy their hardware (I figure cheaper hardware is looming). AVT-852 is not cost prohibitive, but I'd like to know how to make it work before buying. (i'm an unemployed uberhaxor, actual coding will be the easy part given sufficient reference materials).

Fawq the $500+ roadrunner and highway robbery licensing, DIY 0411 solution is more important to me than utilizing my $300 4.8.
89 suburban, D60/aam10.5, eccc-4l80e/L31-tbi/$0d