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Wrong rom dump

Posted: Wed Nov 28, 2018 3:28 pm
by bazzano
I discovered a bug in a rom dump for the system Z80NE (ep382.ic5), due to a typo I made 40 years ago (!!!).
The corrected rom dump is now available on my site here (I have permissions to publish it):

Perhaps do you know who to contact to make a new hash of the rom file, so that the fixed rom works in mame?

Thank you very much.
Roberto Bazzano

Re: Wrong rom dump

Posted: Thu Nov 29, 2018 2:52 am
by Robert
I will put the new rom into the source of Z80ne.

What's the difference?

The original source was written by Roberto Lavarone, was that you?

Re: Wrong rom dump

Posted: Thu Nov 29, 2018 3:14 am
by Robert
Checked the new rom, the one-byte change makes sense, so it has been added.

Thanks for letting us know. :)

Re: Wrong rom dump

Posted: Thu Nov 29, 2018 12:03 pm
by bazzano
Thank you very much.
No, I'm not Roberto Lavarone, he wrote the source but he's another person. :-)

And now a little bit of history... :)

When I manually dumped that eprom 40 years ago I wrote it on a piece of paper, then the original 2708 eprom was broken.
After many years I recreated the eprom starting from the written paper, but thanks to my bad writing skills :) I misread a "CD" and programmed a "C0" in the file (look at the following image: it's the last "CD 78 80").

I never noticed that bug because it's very hard to happen: infact that is part of the error checking routine related to writing to cassette tape, but it can't almost never happen because it could be fired only in case of a hardware communication error between the CPU and the UART, and that's almost impossible.

Now I found a original listing of that eprom, so I noticed the bug. It's never too late... :D

Thank you.