Does the 70 or 90 ns speed matter much? I spoke with a tech at digi key and found that the only in stock item they had was a AT27C256R-70PC chip I wasnt sure if this would work... Where would be the best sorce for a good working chip? They have many 90ns chips but they're all not in stock chips and they claim I must order over 500...
Paul

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90 Red Convertible
100k running great
ZAINO!!!
383 Stroked.... LT4 Hot Cam... Forged Elgen Pistons Scat 9000 Crank Elgen 5.7" rods New Lifters w/ 1.6 Rockers and hardened Pushrods Super Ram Intake Hooker Headers and Y pipe into Gutted Cat with Monza Mufflers (WAY TO LOUD!!) Adj Regulator K&N Shift Kit High stall converter 160 termo, ZR1 Rims.... Red Calipers....Alpine head unit, Kenwood 6x9 4 ways, Polk DX 6 1/2 compnents, MTX 240 amp, Viper 550 alarm,


www.corvetteforum.net/c4/nomar116/

I decided to take the flash prom plunge last week after my first week of burning with
UV's and having problems with chips going bad after erasing. I went online to Arrow and ordered...had them in 3 days. I'm sure they will have what you need in stock. I'm not telling you what to do, but moving to flash was the way to go. I had absolutely no problems.

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'87 Formula WS6 - ZZ4 Crate TPI, Scroggin-Dickey ported heads, LT4 hot cam, 1.6RR, Accel runners, Accel base, ported plenum, Edelbrock 58mm TB, Crane Fireball ignition, SLP cold air, SLP 1 5/8 headers, !cat, Summit exhaust cutout, Walbro 255, Koni yellows, Hotchkis panhard & LCA's, 9 bolt w/3.27's.

Ive been approached about this in the past... I have already bought an awful lot of software for normal recording... What else would I need for flash burning...

What would I want in a non flash eprom....

Actually, you need one less thing to burn a flash prom. The UV eraser is not needed. Go the flash route, AT29C256. It'll be your new best friend.

The chip in these ECMs don't need anything really fast. Anything 150 ns or faster will work, probably even slower ones would but there is not enough of a cost savings and most stock 150 ns or faster anyway.

For my Flash Prom, I am using a 120 ns and it works just fine.

I am looking into the possibiity of having the ECM actually being able to write on to the Flash Prom (for temporary storage or self-modifying tables), but there is no certainty that this will work and you still can only write to an Flash Prom so many times. Temperature supposedly affects the number of times that you can write to a Flash Prom. But IF it does work and excluding the fact that a Flash Prom still can only be re-written to so many times, having a faster Flash Prom (like 90 ns) may be worthwhile.

nevermind

[This message has been edited by Matt87GTA (edited November 13, 2001).]

I assume I would have to use a different program other than tunercat/datamaster.... What prom would I need if I DIDNT use flash prom... And does everyone think I should take this plunge?
Paul

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90 Red Convertible
100k running great
ZAINO!!!
383 Stroked.... LT4 Hot Cam... Forged Elgen Pistons Scat 9000 Crank Elgen 5.7" rods New Lifters w/ 1.6 Rockers and hardened Pushrods Super Ram Intake Hooker Headers and Y pipe into Gutted Cat with Monza Mufflers (WAY TO LOUD!!) Adj Regulator K&N Shift Kit High stall converter 160 termo, ZR1 Rims.... Red Calipers....Alpine head unit, Kenwood 6x9 4 ways, Polk DX 6 1/2 compnents, MTX 240 amp, Viper 550 alarm,


www.corvetteforum.net/c4/nomar116/

Your Tunercat and scanner are fine. I use tunercat and started with 27C128's (MAF) and moved right to the Atmel 29C256 flash proms.

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'87 Formula WS6 - ZZ4 Crate TPI, Scroggin-Dickey ported heads, LT4 hot cam, 1.6RR, Accel runners, Accel base, ported plenum, Edelbrock 58mm TB, Crane Fireball ignition, SLP cold air, SLP 1 5/8 headers, !cat, Summit exhaust cutout, Walbro 255, Koni yellows, Hotchkis panhard & LCA's, 9 bolt w/3.27's.

Are you sure that you're limited on the number of writes to a Flash prom? I didn't think they degraded...

Yes, flash-proms are cycle-limited, but it's WAY more than eproms. Something on the order of 100k cycles.

For the time being... what eprom speed do I want for a non flash prom... I know flash is easier or more convienant but I gotta go with whats working for now and take smaller steps So where should I buy these chips.
Paul

Yes, the 70 and 90 will work.

Do as you wish, but a Flash Prom works EXACTLY the same for an SD car as the 27C256. If you enjoy waiting for your eprom to erase, buying a UV Eraser and only getting 25-50 re-burns before you have to replace them, by all means get the 27C256s.

Yikes! If I don't have the car setup right by 100k tries, I'll probably resort to tuning it with a stick of dynamite...