Just noticed on Mouser's site our 27sf512 chips are now obsolete!
I just ordered 6 chips, hella glad I did...WTF, I thought these chips were super popular. What are we going to do when these run out?
Just noticed on Mouser's site our 27sf512 chips are now obsolete!
I just ordered 6 chips, hella glad I did...WTF, I thought these chips were super popular. What are we going to do when these run out?
Anyone look at Futurlec? There prices are great and they have most of the chips our cars use. They have the 27C512 but i did not see the 27SF512. I am not sure of the difference, though.
http://www.futurlec.com/ICEPROM.shtml
Looks like you can still get the 27c256. The OTP's are less than $2...
The last set of 27SF512 chips I got must have been defective. a few of them would not reprogram after 2 - 3 attempts and my car was acting funny with them. I ended up using chips from a different lot and they were fine. I wonder if "mousers" recomended replacement can be used. Its 804-27SF0207CPHE
Here is more info about it http://www.sst.com/downloads/datasheet/S71152.pdf
Justin
84 Plymouth Voyager LE 2.5 Intercooled Turbo 5-spd - Only 84 Turbo Van!
89 Dodge Caravan ES 2.4 SRT-4 Intercooled Turbo (46 trim, OS Valves, CP Pistons, Eagle Rods, NPR IC) Built 31th trans
91 Dodge Shadow Convertible 2.5 Intercooled Turbo A555 5-spd
01 Pontiac Grand Prix GTP - 3.8 supercharged! Only 5K miles....
01 Subaru Forester - Daily Driver
07 Yamaha FJR 1300 140+ HP on 2 wheels
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Right but aren't those once and done chips? No erasing? It's just an Eprom, not an eeprom. That stinks.Originally Posted by ShelGame
Edit-yeah just figured out that OTP means one time programmable...drrr. I thought all 27c256 chips are OTP though...???
Here's a list of mousers 27c256 chips-
http://www.mouser.com/Search/Refine.aspx?Keyword=27c256
Last edited by moparzrule; 03-10-2009 at 10:13 PM.
Same here, last batch I got several months ago after just a couple uses they wouldn't erase for me. It would keep going up to like 49% and stop, never completely erase...and then it wouldn't let me burn it either.
That's a 2Mbit (I think) chip. It's a 32-pin chip. Won't fit our boards. The biggest chip we can run is a 512.
Maybe I need to get back to work on those flash modules...
That is the same thing that was happening to mine. I had about 5 that would not erase. I thought it was my burner so I pulled the chip I got from you and I tried to erase and program that one. It worked fine. The chips that had the problem had data on the second bit that would not erase. On my van these chips were also causing weird problems that were driving me nuts. I would install a chip and after driving for a while it would go pig rich and stay there (10.0). I pulled the chip and installed another chip with the same cal and the problem was fixed. I gave one of the chips to a friend who is an electronics engineer that deals quite a bit with eproms. He told me there were "talks" that some eprom chips were actuially cheap used Chineese chips that were cleaned and being sold as new chips.
Justin
84 Plymouth Voyager LE 2.5 Intercooled Turbo 5-spd - Only 84 Turbo Van!
89 Dodge Caravan ES 2.4 SRT-4 Intercooled Turbo (46 trim, OS Valves, CP Pistons, Eagle Rods, NPR IC) Built 31th trans
91 Dodge Shadow Convertible 2.5 Intercooled Turbo A555 5-spd
01 Pontiac Grand Prix GTP - 3.8 supercharged! Only 5K miles....
01 Subaru Forester - Daily Driver
07 Yamaha FJR 1300 140+ HP on 2 wheels
85 Honda Nighthawk 450
94 Bobcat 763 Skidloader 2.2 Kubota Diesel
SV-SDAC Member
Whats wrong with using a 256 chip?
1989 FWD Turbo Caravan-2.5 TIII, GT35R, auto, a/c, cruise, pwr windows/locks, fully loaded with interior and ran with full exhaust. RETIRED FOR A FEW YEARS!12.57@104 :O)
1984 Chev Getaway van, 6.2 Diesel with a remote mounted turbo setup burning WMO-For sale.
2003 GSW 2.0L TDI, auto, fully loaded, modified, 360K-wife's.
2004 GSW TDI, 5 speed, fully loaded, modified.
Aurora ignition wires for sale. Link to info
Super60 roller cams or custom/billet cams. Link to info
Nothing at all...
Nothing, the nice thing about the 27SF512 chips is you can erase and reprogram them over and over.
Justin
84 Plymouth Voyager LE 2.5 Intercooled Turbo 5-spd - Only 84 Turbo Van!
89 Dodge Caravan ES 2.4 SRT-4 Intercooled Turbo (46 trim, OS Valves, CP Pistons, Eagle Rods, NPR IC) Built 31th trans
91 Dodge Shadow Convertible 2.5 Intercooled Turbo A555 5-spd
01 Pontiac Grand Prix GTP - 3.8 supercharged! Only 5K miles....
01 Subaru Forester - Daily Driver
07 Yamaha FJR 1300 140+ HP on 2 wheels
85 Honda Nighthawk 450
94 Bobcat 763 Skidloader 2.2 Kubota Diesel
SV-SDAC Member
So there's no 256 Eeprom's????? If so, bummer,
1989 FWD Turbo Caravan-2.5 TIII, GT35R, auto, a/c, cruise, pwr windows/locks, fully loaded with interior and ran with full exhaust. RETIRED FOR A FEW YEARS!
1984 Chev Getaway van, 6.2 Diesel with a remote mounted turbo setup burning WMO-For sale.
2003 GSW 2.0L TDI, auto, fully loaded, modified, 360K-wife's.
2004 GSW TDI, 5 speed, fully loaded, modified.
Aurora ignition wires for sale. Link to info
Super60 roller cams or custom/billet cams. Link to info
Not anymore. Seem to all be obsolete - at least in the 28-pin DIP package we need. You can still get them in the surface mount packages...
Hmmm, so I guess I wanna socket my SMEC with a PLCC type socket rather than a DIL then....
Is that company in China still making AA bodies? Wonder what the SBEC in those looks like these days.
OK, after looking at some datasheets I may have found an answer. I think that if we take pin 27 from the board on our ecu and connect it to pin 1 on the AT28C256 it will work. That seems to be the only pin that's different between the at28 and at29 eeproms (I actually checked vs the sst datasheet). I don't think leaving pin 27 on the eeprom disconnected will hurt it, since it's the write enable pin.
Has anyone tried this? I've got no problem being the guinea pig, but I won't bother if someone has done it and found out it didn't work. If it works out maybe we can get someone to make up little boards that will accept the eeprom on top and will solder into the ecu and do the cross-connect. Or if you're really fancy, maybe go from the PLCC-32 to DIP-28 with an adapter and remap it.
Yeah, that's actually the chip that the DIY flashable instructions call for. You just bend the pins back over the top and run a wire or two.
I also use the same chip for my flashable modules, though in a surface mount package...
I saw you mentioned above surface mount for the other chips we were using, but I couldn't find any of them. There's plenty of tsop to dip-28 adapters out there, but I only managed to find 2 plcc-32 to dip-28 that looked like they had a chance of working. And I couldn't find any chips on mouser, that they were still stocking and not warning about discontinuing, that would drop right in.
Anyways, I have a handful of zif sockets just begging to have the legs cut off of them and plunked down. But I guess if you're already using them, that means the ecu won't have a problem reading from them as long as that 1 address line is put in the right place.
By the way, if a chip looks like a promising equivalent but the data lines are crossed up, or in different order, it should still work, but you'd have to program it that way... i.e. don't tell the programmer it's a different chip.... or if it is too smart.. make a util to swap round bits in the byte so they turn out the right way round.
Exactly. It's going to be a matter of programing/erasing the chip as a at28c256 and treating it as such outside of the ecu. We should only be making the mod to swap pin 1 for 27 when on the ecu.
It's address line 14 that's on pin 1 of the at28c type chips. Where on the equivalent sst/at29c series chips address line 14 is on pin 27. So, when the ecu has a signal it normally puts for address line 14 (on pin 27 normally) it needs to go to pin 1 instead. Pin 27 is write enable on the at28c chips , so it doesn't even need to be connected to the standard ECU since it shouldn't ever have a signal on it (Rob's in car flashable utils are a whole different ball game).
I think, if it works, it may not be for the weak of soldering iron.
I'm actually toying with the idea of getting a plcc 32 adapter and trying to use the more common 1/2/4mbit flashes, since those won't be going anywhere any time soon.
i bought a few of the 2mbit 32 dip's to do some testing to see if they will work as long as the address pins are set correctly and a small adapter is made.
im also gonna try making a 4 bit binary counter with a debounced switch so that i can cycle through the A14, A15, A16 and A17 states and select 16 different cals on one chip.
when the daytona goes on the road ill be doing this.
Brian
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