22 Mar
2022
22 Mar
'22
6:56 p.m.
On Monday (03/21/2022 at 09:17PM -0700), Glen Slick via cctalk wrote:
On Mon, Mar 21, 2022 at 8:25 PM Chuck Guzis via
cctalk
<cctalk at classiccmp.org> wrote:
[...]
The PROMs are most likely house-labeled Intel commodity parts with
JEDEC-standard pinouts, so it should be fairly easy, using an EPROM
reader, to figure out if these are 8KB, 16KB, 32KB or 64KB devices.
Some device programmers can read the manufacturer and device ID codes
from a device, if they are implemented. That would be another way to
check for a Intel standard part.
Intel 27256 - 89h / 04h
Intel 27C256 - 89h / 8Ch
[...]
Trying not to hijack the thread too much but I have an Intel D27C256-200
here in my TL866II+ programmer and it returns ID 89h / 8Dh.
The TL866+software actually fails to program it if the "Check Id"
feature is enabled as it complains about ID mismatch. But if I disable
that, it programs correctly and works in-circuit without issue.
Without disabling the Id check, there would be no way to program an
Intel 27256 on this programmer since there are no other 256K-bit Intel
offerings in the menu-- so I am suspecious of the situation.
Any idea why some Intel 256K-bit PROMs are 89/8C and some are 89/8D??
Chris
--
Chris Elmquist