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HP-67 not behaving?
08-30-2022, 01:58 AM (This post was last modified: 08-30-2022 02:00 AM by teenix.)
Post: #9
RE: HP-67 not behaving?
The faulty ROM will be either 1818-0231 or 1818-0232. I'm not sure which as both of these ROM's I have on the bench have failed RAMs.

I might be able to get a working one to read, if so I will post the serial number.

1818-0228 (67 and 97), has RAM $00 - $0F
1818-0226 (67 and 97), has RAM $10 to $1F
1818-0231 or 1818-0232 (67), have RAM at $20 to $2F, and $30 to $3F but not sure which one.
You need to replace the one with RAM $30 to $3F.

I am making progress on ROM replacements and you never know, I might be able to offer one in the not too distant future. I know my ROM decoder works, but the ones with RAM included are more complex.

cheers

Tony
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Messages In This Thread
HP-67 not behaving? - markhen - 07-27-2022, 06:03 AM
RE: HP-67 not behaving? - teenix - 07-27-2022, 10:09 AM
RE: HP-67 not behaving? - markhen - 07-27-2022, 03:30 PM
RE: HP-67 not behaving? - AndiGer - 07-27-2022, 04:31 PM
RE: HP-67 not behaving? - markhen - 07-27-2022, 05:18 PM
RE: HP-67 not behaving? - Duane Hess - 07-29-2022, 12:36 AM
RE: HP-67 not behaving? - markhen - 07-29-2022, 04:38 AM
RE: HP-67 not behaving? - markhen - 08-29-2022, 11:56 PM
RE: HP-67 not behaving? - teenix - 08-30-2022 01:58 AM
RE: HP-67 not behaving? - Dreato - 09-02-2022, 04:11 PM
RE: HP-67 not behaving? - markhen - 09-03-2022, 11:34 PM



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