Alright gang here is the skinny. It works and this is how I did it....

I used the pocket programmer which flashes the 29C256 and automatically erases it prior to writing the new bin.

I have my 29C256 mounted to memcal using a ZIF socket as described in Traxion's prom burning article. I would assume you would be able to apply the same technique if trying to program a 27C256 chip for a 165ecm.

I selected the 29C256 chip on the option menu and wrote a 6E bin from addresses 04000 to 07FFF. I tried a couple of variations on the addresses but this is the only combination that worked.

It was mentioned in a previous post that you can probably achieve the same results by programing the bin to both halves of the 29C256 chip. I didn't use this combination because I wanted to find the specific address that is required.

Hope this answers "THE BIG" question everyone has been asking. If I missed anything let me know.

Later All

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87 Iroc 5.7, AFR190, SLP Cam(218/224), SLP 1 5/8 headers & cat back, Random CAT, SLP Runners, 48mm TB, custom chip(by me), Vigilante & Probuilt trans.

 

You beat me to it. I just gone done testing it out 2 minutes ago. It works great so far. Now the tuning begins.

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87 IROC-Z 305 TPI gears, exhaust, converter
14.70 at 94.1 mph
Minirammed 377 for spring

[This message has been edited by Scott 87 IROC-Z (edited May 04, 2001).]

 

Thanks for the detective work. Where can I buy 29c256 proms?

 

Nevermind. I found them.

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89 Six Speed FX3 coupe
More Performance 396cid specs:
Callies 4340 crank 3.875 stroke
Lunati Pro-Mod 5.85" rods
SRP Pistons 14cc dish
Comp Cams Custom cam 550 lift 220/229 duration
10.8:1 compression
AFR 195 competition ported heads
Miniram and TPIS 1 3/4" headers

 

where did you find the 29c256's, Was it JDR, cause I found them there but there service for us canadians sucks, does anyone know of another source?
Also when programming due you change the start of bin adress to 04000 or just the start of device?
Are you using the pocket programmer in windows or one o the dos programs?
Thanks, this is great news.

 

due, I mean do

 

1. I ordered the 29C256 Atmel proms through JDR.

2. When programming I changed the start address to 04000 and the end address is 07fff. I left the start device at 00000. I used the pocket programmer in Windows. I got a copy of the most recent windows version 1.10 from Intronics.

The first time I launch the program it will program the first chip no problem but if I try to do another it won't program. So I just close the application and reopen it. Programs the chip again no problem. Go figure.

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87 Iroc 5.7, AFR190, SLP Cam(218/224), SLP 1 5/8 headers & cat back, Random CAT, SLP Runners, 48mm TB, custom chip(by me), Vigilante & Probuilt trans.

 

Canadian Beast, I found Insight at http://www.insight-electronics.com/c...gin=order_page really good to order from. However, they do have minimum value of order.

I ended up ordering 12 of them and they had the order couriered to my home in a couple of days. Also, I was swamped with requests from people to take any "extra" off my hands, especially people in Canada because they have the same problem. I hadn't even intended to resell the "extras" and I could have easily sold twice as many as I had purchased. Consider organizing a Canadian Group Purchase for those interested. Even when you tack on the portion of the shipping, GST, PST and postage to each chip from the Insight Order, it's still a hell of a lot cheaper than the US$18.00 shipping charge that JDR tacks on to a Canadian Order (if you get it) along with the GST and PST the Post Office collects from you. Lastly, if you DO get your order, it still takes over a week to get to you.

If you are a Canadian, buy from Insight, not JDR.

 

BTW, when you click on the link to Insight, select "29C256" as your keyword. Though they will show 28 variations on their order form (phone them, its easier), only about 7 are "on hand" and only 2 of those are useable on your ecm (AT29C256-12PC and AT29C256-15PC).

The -12PC means 12 - 120 nanosecond speed, P - PDIP: the eprom pin connector variation needed for your ecm and C - Commerical: Grade of the temperature range of the eprom. I - Industrial has a greater temperature range than Commercial, but Insight doesn't actually stock those so you are stuck with Commercial, which work okay.

The other eprom, the -15PC is a slower 150 nanosecond eprom. While it is slower, it is still more than ample quick enough for your ecm. Take the 12s if available just because they are slightly quicker, but the 15s will work.

 

Thanks 87iroc350. Did intronics send you the update for free? What did it change?

Thanks Glenn I just ordered 12 of them. I know what you mean about JDR I tried to order some 27c128's from them a couple months ago. It all went through like normal so I began to wait after a couple weeks I emailed them and they told me that they cancelled my order, no explanation they just cancelled it. They make me mad.

I think I'll just keep them, I've got lots of friends with similar interests around here.
Do you think you could use them in an 89 tbi truck. They have a 32kb prom correct? Wouldn't it work to program from 07000 to 07fff????
Thanks alot

 

I would be more than willing to organize a GP for these chips for any interested canadians here.

email me at L98_GTA@hotmail.com

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89 GTA 350 T-Tops White/Grey----Looking for a little more performance than stock!

 

Hey, I just received my 18 chips from Arrow. $4 bucks apiece. They are all spoken for, however. Should I get some more??



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Daniel Burk
http://www.isthq.com/~dan/fcar.html
'84 Trans Am WS6/L69
KB SFC, Moser axles, Torsen Diff., Spohn Adj. torque arm,
Ported 305 heads w/1.94"intake valves, Comp Cams XE262H, Griffen alum. radiator,
Turbine Technologies 2500 stall converter, underdrive pulleys, Crane Hi-6 & more.
1.05g skidpad verified.
Best of 14.039 at 100.82 MPH in Stanton, MI
New! 275-40-ZR17 tires on ROH ZS 17 x 9.5's

 

Will these chips work with a laptop? Has any one done it yet?

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87 Iroc-Z 305 TPI
Dynomax exhaust
modified MAF & airbox
3-10" JL subs
Eclipse components

 

CanadianBeast, yes intronics did send me the free update due to I just bought the pocket program a couple of months ago.