I cannot find a datasheet by any of the numbers silkscreened on these ICs.
Could these be proprietary IBM P/N numbers?
https://www.dropbox.com/s/f6rvemx9ldbbv5x/EPROMS1.jpg?dl=0
No need for a Dropbox account, close the login pop up and you can view the
image.
Thanks
Don Resor
On 3/20/22 20:59, D. Resor via cctalk wrote:
I cannot find a datasheet by any of the numbers silkscreened on these ICs.
Could these be proprietary IBM P/N numbers?
Yes, they are. But, very likely standard 27xx series of
EPROMS, all you need to know are how many address bits there
are and you
This is the CPU board out of a first generation 1982-83 IBM Electronic 85
Typewriter (Electronics Driven Selectric).
I was looking to archive the software/firmware from these. The machine was
exposed to some dampness. Corrosion has ensued on the interface connector
between the CPU and driver
