Altair parts substitutions

From: allisonp <allisonp_at_world.std.com>
Date: Mon May 22 17:33:03 2000

>> The 8101 dual-port 256bx4 RAM is no longer available, but Jameco has a
5101
>> which looks like a likely sub.
>
>Check the timing specs; the 5101 might be slower.


To run at 8080/2mhz it needs to be 600ns or better. In 1975 5101s were
typically
1000ns or the fast ones at 850.

>
>Also, 8101 is just a different marketing designation for 2101, just like
>8702 for 1702, etc. The 2101 should be easier to find.
>
>Apparently Intel's marketing people didn't think that engineers would be
>able to figure out that their standard RAM, ROM, PROM, and EPROM
>products would work with the 8080, so they introduced 8xxx-series part
>numbers for them.


No, not quite. It was a marketing thing to "bundle" parts with like numbers
to indicate compatability for sales. The best of those was the 8205 that
was really a 74138 but intel kept claiming it was a similar but gltich free
part. I cracked one open to prove a point and th intel part was a TI 74138
die. Kitting, the name used by those in the trade back then was intels way
of insuring they didn't get cherry picked for the 8224 and 8212 while AMD
got the 8080 order along with someone else getting the ram order.

Allison
Received on Mon May 22 2000 - 17:33:03 BST