27sf512 chips obsolete???

[WickedShelby88]

Looks like a lot of the chips that we can use are being discontinued. Many of them requiring to be programmed differently as well in order to work. I'm guessing the pre pentium generation of chips is being phased out. On that note I called Moates up and they have plenty of the 27SF512 chips. In fact the person that answered said in light of the fact they are now obsolete they have even more ordered for stock. So there are plenty for now. I think working on an alternative is a great idea though as these won't be there much longer.

[turbovanman²]

^^^^^^^ Is that your bike?? If so, sweet, CBR400RR? or RC30/31?

[risen]

Is anyone interested in adapter boards to take the atmel at28hc256 and make them usable on our ecus? The board would be like 5$, plus either 10$ for a ZIF or another 1 or 2$ for a regular socket. The EEPROM is around 7$ from mouser. So it's a total of 22$ for a ZIF adapter or 15$ for a reguar machine pin socket adapter with eeprom.

I'm guessing the total additional height would be between .17 and .25 inches, so I don't know how this works out for SMECS.

I'm going to have a test board made up anyways, but I'm just wondering if there's demand for this sort of thing.

[TommyT]

Futurelec and mcumall has PLCC232 to DIP28 adapters for $8 or less. Futurelec sells eeprom 28C256 PLCC chips. Could that be a good, easy alternative?

[RoadWarrior222]

Probably still need an interposer to get the pinout right. However, DIL to DIL is easier to do for a one-off perfboard and wrap.

BTW you can probably yank quite a few PLCC EEPROMs off old motherboards.

[risen]

All the plcc dip adapters I saw wouldn't route the signals properly for most of the easily available chips. Quantum's working on some stuff for this, so unless someone *really* wants the 28-28 adapter for the chips I mentioned above, I'm going to let him handle it. His stuff is much further along than I am and has more features, too.

[88C/S]

I recently ordered a five-pack of SST 27SF512 chips from Xenocron, Moates will sell you 20+ for #4.25 ea.

[tryingbe]

Buy 10 and get it for $25.

http://www.xenocron.com/eprom-chip-s...ack-p-151.html

[risen]

It's more about what's going to happen when the secondary suppliers are out of stock. Once moates and other places run their stock down we're going to need to look somewhere else. Or people will be stuck buying used chips, like some still do with the at29c256 chips.

[contraption22]

I have this chip here on my desk.
This is what it says on the back.

ATMEL
AT27C040
90PU
0740

I have a bunch of them that have out-of-date info on them and I'm about to toss them. Just checking to see if they would be of any use.

[risen]

I have this chip here on my desk.
This is what it says on the back.

ATMEL
AT27C040
90PU
0740

I have a bunch of them that have out-of-date info on them and I'm about to toss them. Just checking to see if they would be of any use.

Assuming I understand atmel's numbering scheme, it seems they are a 32 pin dip package (1 row of 16 pins on either of the long sides) and 90ns access time. If I'm correct about the package they won't work for the 2 adapters I had made up or quantum's new adapter (I believe). I suppose you can try and retrofit them to something, but I'm not sure how much of a hassle it will be.

[minigts]

Assuming I understand atmel's numbering scheme, it seems they are a 32 pin dip package (1 row of 16 pins on either of the long sides) and 90ns access time. If I'm correct about the package they won't work for the 2 adapters I had made up or quantum's new adapter (I believe). I suppose you can try and retrofit them to something, but I'm not sure how much of a hassle it will be.

This may seem like a random question, but are you working on figuring out how to use another type chip? Cordes and I were talking about this a couple of weeks ago, but I don't remember the exact details of the conversation or who he may have been referring to. Thoughts?

[Aries_Turbo]

i was working on an adapter but i got side tracked... as usual.

Brian

[risen]

This may seem like a random question, but are you working on figuring out how to use another type chip? Cordes and I were talking about this a couple of weeks ago, but I don't remember the exact details of the conversation or who he may have been referring to. Thoughts?

The only chips I looked at were the 28hc256. They'll work with 1 address line re-routed. I believe Rob is actually using them for his flashable smecs. I'm not going to actively pursue the 28hc256 futher because Quantum's working on some plcc adapters.

Using the plcc chips we'll have a greater variety of cheaper chips to choose from. Plus, I'm sure that the plcc chips will be around for a while and there's still many manufacturers. So at this point the plcc type chips seem to be the best option. Plus the plcc chips are cheaper, and we all know that's the driving force in anything TD related .

[contraption22]

Assuming I understand atmel's numbering scheme, it seems they are a 32 pin dip package (1 row of 16 pins on either of the long sides) and 90ns access time. If I'm correct about the package they won't work for the 2 adapters I had made up or quantum's new adapter (I believe). I suppose you can try and retrofit them to something, but I'm not sure how much of a hassle it will be.

Thank you very much. I guess I can chuck them.

[minigts]

The only chips I looked at were the 28hc256. They'll work with 1 address line re-routed. I believe Rob is actually using them for his flashable smecs. I'm not going to actively pursue the 28hc256 futher because Quantum's working on some plcc adapters.

Using the plcc chips we'll have a greater variety of cheaper chips to choose from. Plus, I'm sure that the plcc chips will be around for a while and there's still many manufacturers. So at this point the plcc type chips seem to be the best option. Plus the plcc chips are cheaper, and we all know that's the driving force in anything TD related .

Let's assume a couple of things. First, I don't know what those are. Second, I have a SMEC. Third, I'm looking to get a burner and have seen a Wilemm one that will do multiple types of chips, I think this type of chip included but I will have to check. Because there could be a shift in the types of chips we can use, is this something that seems to be doable in the foreseeable future or would these types of chips only work on the LM style computers?

I guess my questions stem from whether or not I should just wait to buy the burner and chips once these types of chips are usable. I could buy one that would burn all types now and then buy some $5 chips that will drop right in. However, I could hold off on buying the stuff if I knew I needed a chip adapter, the newer style chips and a burner for the chips. Saying I'm new to this stuff doesn't explain just how new I am to it. Seriously, thanks for the information.

[risen]

Let's assume a couple of things. First, I don't know what those are. Second, I have a SMEC. Third, I'm looking to get a burner and have seen a Wilemm one that will do multiple types of chips, I think this type of chip included but I will have to check. Because there could be a shift in the types of chips we can use, is this something that seems to be doable in the foreseeable future or would these types of chips only work on the LM style computers?

I guess my questions stem from whether or not I should just wait to buy the burner and chips once these types of chips are usable. I could buy one that would burn all types now and then buy some $5 chips that will drop right in. However, I could hold off on buying the stuff if I knew I needed a chip adapter, the newer style chips and a burner for the chips. Saying I'm new to this stuff doesn't explain just how new I am to it. Seriously, thanks for the information.

Just some background info: PLCC is a type of 'package' for a chip. The standard chips on our ECUs are what's called DIP (or DIL). DIP chips are rectangular and have 2 rows of pins coming off of their longer sides, and are the older style of chip that gets solderd through the board. PLCC stands for Plastic Leaded Chip Carrier. Those chips are normally square (or very close to) with each side having a set of pins on it and usually get soldered to the surface of a board (or put in a socket). Hopefully that stops some of the head scratching when PLCC is mentioned . You can have the exact same chip, just in 2 different packages. SST used to do it, you could get a 27sf512 in a 28 pin dip or a 32 pin plcc. So, it's not only the type of chip but now we also need to be conscious of the package.

You can buy adapters for the plcc chips that will allow you to burn them in a willem burner (some burners come with them). Plus, plcc is a pretty common package. Look at a network card or motherboard, there's a good chance you'll find a plcc type chip in a socket for the bios or bootloader. Also, since everyone else here uses a willem (I have one, but perfer my moates) I doubt we'd go to something that couldn't be burned with a willem, so you're pretty safe there.

The smec and LM use the same type of chips, so whatever works in a LM will work in a SMEC. The only worry going form LM to SMEC is that the chip is big enough to hold a SMEC cal, but it's hard to find chips that are smaller than 256k at this point, so that's not really a big concern. It's the SBEC that needs the 'special' chips with the latch, and was the reason that Quantum built his original adapters.

Moates and Xenochron still offer the 27sf512 chips, so if you're starting now, I'd buy a few of those and the willem. It's just that the 27sf512 aren't being made new any more, so we're going to need options for new chips at some point. Once the secondary suppliers are out of them, people will have to resort to buying used chips on ebay if we don't have a way forward.

Just as a side note: I looked at the datasheet for the 27c040 and they're actually a OTP (one time programmable) chip. So even if they were the right package and pinout, they're worthless for anything other than 1 cal because you can't erase and rewrite them.