25 Sep
2003
25 Sep
'03
9:24 a.m.
After popular demand :-) I am posting the URLs for said PCB:
Top View (with ICs):
http://www.series80.org/Pictures/HP-Prog-ROM-Top.jpg
Bottom view:
http://www.series80.org/Pictures/HP-Prog-ROM-Bottom.jpg
Installation Note for the programmable ROM drawer:
http://www.series80.org/Manuals/HP82929A.pdf
Notice the custom ICs between the TTL components and the bus.
Since the HP-85 bus uses 12V clocks and +6V logic, and that the
bus is bidirectional (thanks Tony), does anybody have suggestions
on how we can construct a replacement of the custom ICs?
Thanks
**vp
