Eprom replacement

[Billman]

Is it possible to replace a 87C257 with 27SF256?

[ManiacuV6]

You can find an inverter so you can use a 27Sf256 or 27Sf512 . I need to search for website.

[Billman]

I want to use it on an Opel/Motronic ECU.

[SteveH]

Why do you want to change it? 87C257's are easy enough to get hold of.

[prj]

You can find an inverter so you can use a 27Sf256 or 27Sf512 . I need to search for website.

The correct word is "latch".

[ManiacuV6]

PRJ is da master ) If you don't remeber the word you need to explain in another way , right ?

[prj]

And this is the adapter.

http://www.boostbutton.com/catalog/product_info.php?products_id=34

I helped the author redesign it to fit it into the Motronic ECU.

[Billman]

Cool!!! Thanks a lot

[pfi]

Link to the latch doesn't work,
but, is a latch needed for 27c256 ? AFAIK it's pin-compatible with 87c257 ? (27c512 is different)

[prj]

Of course it's needed, otherwise the chip won't latch the inputs, it uses same bus to access RAM and ROM.

[pfi]

87c257.jpg27c256.jpg
hmm, looks pretty equal to me ...

[prj]

So you think that every chip with same pinout operates the same?
I don't think you have any clue what I said in my last message. Maybe it's time to go back to school.

[pfi]

The 27c512 has different pinout so obviosly needs a latch
27c512.jpg

[prj]

The 27c512 has different pinout so obviosly needs a latch
27c512.jpg

You have no clue what a latch is. Are you trolling? Or just ignorant and determined?

27C512 with latch adapter will work exact the same as 27C256 with latch adapter, there's zero difference between the two besides an extra address pin.

[pfi]

Yea, mby I need some more education ...
please enlight me