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Which EPROM box to use with two equal length EPROMS
Message #1 Posted by PeterP on 25 Apr 2008, 6:50 p.m.

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

      
Re: Which EPROM box to use with two equal length EPROMS
Message #2 Posted by Diego Diaz on 25 Apr 2008, 9:33 p.m.,
in response to message #1 by PeterP

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-
-03   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.

            
Re: Which EPROM box to use with two equal length EPROMS
Message #3 Posted by PeterP on 25 Apr 2008, 10:30 p.m.,
in response to message #2 by Diego Diaz

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


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