AT29C256 with TBI or TPI (Autoprom and TPv5)

[dyeager535]

Apparently I managed to kill a couple of 27SF512's today. Dug into my box of tuning stuff, and realized I had a few of the 29C256 chips. Hooked up the Autoprom (APU1) and TP5, to upload the '747 and '165 bins to the 256. Both fail at erasing the chip. Reading the chip shows "success", although I have no idea what they were originally used on.

The addressing appears to be correct, as TP5 has the 256 already listed as an option.

I'm able to program the 512's with no issue. Everything seems to indicate the 256's should work with what I have, but I'm having no luck. Probably a setting I'm missing, but again, since TP already has the 256 listed (as it does for the 512, among others), not sure what setting I could be screwing up.

It's not a huge deal, I've got a couple 512's left, but with them not being made anymore (I know you can still get them, but $5/each), I should probably use the stuff I already have.

Any ideas?

Thanks!

[EagleMark]

How do you kill a SST 27S512 chip? I've erased and burned one dozens of times, even had offsets wrong and erased even burned one at wrong voltage once? Loads of fakes on eBay cheaper but hardly any look exactly like the ones from Moates that last forever.

Anyway sometimes if you move offsets then click on chip offsets are wrong, Shouldn't be but you wouldn't be the first.

File Size
Chip
Buffer Start -> End
Chip Start -> End

4k (4096)
AT29C256
000000 -> 000FFF
007000 -> 007FFF

16k (16384)
AT29C256
000000 -> 003FFF
004000 -> 007FFF

32k (32768)
AT29C256
000000 -> 007FFF
000000 -> 007FFF

http://support.moates.net/2010/04/05...using-offsets/

[dyeager535]

256.jpg Everything looked ok here from what I could tell?

[RobertISaar]

i haven't personally "killed" a 27SF512 before, but i have damaged one of the address lines on one. luckily it was the highest address line and i was only using a 32KB program, but it was stupidity that caused it.

[dyeager535]

but it was stupidity that caused it.

Is that a not so subtle hint? lol Guaranteed, in MY case it was stupidity. Especially to get two of them.

Was unaware that inserting backwards would do it. Was getting a flickering SES, assumed it was a bad connection after chip insertion, which is why I tried another one. :(

[RobertISaar]

mmm.... the only time inserting it backwards should cause it would be if using it to replace a 2732 chip. i've done that on accident a few times before in applications that originally used 27C256 and didn't damage them.

i've accidentally erased a 29F040 backwards before as well.... heated up REALLY quickly, but didn't kill it.

in may case, i was building a homebrew 2timer and forgot to remove a connection, so when the ECM powered up, it sent a large current at +5V through the address line.... :O

[dyeager535]

Hmm, only thing I can think of that I did wrong was put them in backwards...the one chip was the one he was running when he got here, I simply pulled it out and put the "new" one in that I had just burned. When the new one didn't work I swapped back to the original one (that was just working), and it gave the same indications that it was "bad". Came back in, burned the same image to another 512, and it worked fine.

This was in a '747 BTW.

[RobertISaar]

1227747 = originally 2732, so that is one of the ECMs that will kill a backwards chip.

[dyeager535]

There was a dim glow way back in my head when I read 2732 but it never got bright.

I marked the case of my 165 so I didn't make this mistake, the 747 case is now so marked as well.

[EagleMark]

7747 or any C3 notch to notch in holder and it will only go in one way, inside towards netres. With adapter still inside towards netres. Burned in brain!

Memcal outside, opposite of chip ECM. Burned in brain!

If any are different I'm screwed...

[RobertISaar]

well, not that there are any adapters out there (yet.... :)), but the 93-95 northstar MEMCALs are interesting.... they have two 64KB PROMs in 1 MEMCAL...

[EagleMark]

I'd like to see one of them! Sounds like an interim PCM before the 94-95 LT1 type...

[RobertISaar]

somewhat.... they are both P66 units, just one has flash PROM, the other with EPROMs.

oh, and vastly different engine/transmission control schemes.

[JeepsAndGuns]

Ya know I have often wondered why no one has made a xdf for the northstar pcm yet. If people are making crank triggers and using their DIS, why not hack the pcm too, then just make a cam sensor and now you have DIS and sequencial injection!

But back on topic, sorry for the hijack.

[EagleMark]

We seem to hijack everything with ideas that turn into good conversations. If we split all threads that were hijacked we would have 10 times the threads!

This is why I need to install a better search program.

I'm guessing the reason no XDF is not many Northstar owners want to mess with their PCM, then no adapter so would have to solder in new EEPROMS, then a disassembly of the bin would be a huge undertaking. I can't even find one for $EE LT1 but I know there's one out there because we have an XDF...

With that car being a 1995 and a sweet engine it may become popular swap as it's getting old and will be in JY... but the complexity of engine and cost of a rebuilt would be outragous... 32 valve engine!

Look at the supercharged 2006 to 2009 engine... 469 HP
http://en.wikipedia.org/wiki/Northstar_engine_series