Re: Looking for Videx VideoTerm ROM images

["Michael J. Mahon" <mjmahon@aol.com>]

Ian Primus wrote:
> On Jun 8, 10:02 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:
>
> > If the character generator EPROM is bad, then the patterns displayed
> > will be completely consistent--if you repeat a character, you'll see
> > lots of copies of *exactly* the same bit pattern--as if you have some
> > "alien" font.  ;-)
> >
> > If this is not the case, then I doubt it's the EPROM.
>
>
> I don't think it's the character generator ROM. I think it's the
> program ROM. There has to be some code mapped into ROM space ($C300)
> to handle communication with the card when you do a PR#3. In my case,
> the 40 column display gets corrupted, and the computer hangs up. No 80
> column output at all.

In that case, a quick look at the $C300 code space in the monitor
should reveal any obvious corruption.  Of course, if it's just "one
bit" somewhere, that's a harder problem.

-michael

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