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Full Version: Which EPROM box to use with two equal length EPROMS
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Hi,

Lucky me has located a few EPROMS (PPC2, PPC3, Assembler, NFC, etc) yet the majority of them is housed in two 24 legged EPROMS of same size. Now I checked the David Assembler box and the HHP handheld one and in both there is a longer EPROM (I think it is 28 legs) for the L8 bit EPROM and a shorter (24 legs) for the U2 bits. But most of my eprom sets consist of 2 EPROMS of same length (the shorter one) but are still labeled as L8 and U2.

Which EPROM box do I need so that I can read those roms? (Not all of them are on TOS so it would be nice to read them out and make them available. I mean, we have to have something to fill these new monsters of capacity MLDL2000 v2 and NoV64...)

Thanks for any kind help and tips,

Cheers

Peter

Hi,

2716, and 2732 are both 24 pins, while 2764, 27128 and 27256 are all 28 pins. I can't think of ROM images by those days burnt into bigger EPROMS.

In any case, if you're going to plug a 24 pins EPROM into a 28 pins socket, just remember you *must* align it to the bottom pins, thus EPROM's pin 1 will connect to socket pin 3.

-01         28-
-02____ ____27-
-03ยบ U 26-
-04 25-
-05 24-
-06 ___ 23-
-07 / \ 22-
-08 | | 21-
-09 \___/ 20-
-10 19-
-11 18-
-12 17-
-13 16-
-14_________15-

Hope this helps.

Diego.

Great Diego,

That is exactly the kind of info I was hoping for. I will try when I am back in NYC and let you know of the result.

Thanks again!

Cheers

Peter