In message <[email protected]>, "Skip Withrow" wr ites:
>The processor in this unit is a ROMed R6500/1 (cousin of the 6502). I fear >that perhaps a bit in the ROM is being read incorrectly (in the switch read >routine). My guess is that there is no way to read the code out of this >part. In general, I can highly recommend that everybody try to get copies of ROM and EPROMs of your vintage gear as backups. If the chips are soldered in, you can avoid unsoldering them, by catching the contents on the bus with a logic analyzer, while the ROM checksum test runs. A lot of HP kit have undocumented "read memory" commands that can be used over GPIP, trick is to guess what it is called and how it works without a ROM image to disassemble. Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [email protected] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
