Televideo 925 character rom dump

[Guy Dunphy]

When I saw this thread I thought 'Oh, I have a 925!' Which was working last time (years ago.)
But wouldn't you know. When I checked, it's a Televideo 924. Off by one.

But perhaps the character ROM content is the same? 
Anyway I will see if it still works, and secure all the ROM images. Today.

I have the user manuals, but does anyone have schematics for the 925 & 924?

Guy


At 09:38 AM 23/04/2019 -0700, you wrote:
>On Tue, Apr 23, 2019 at 8:25 AM Patrick Finnegan <pat at vax11.net> wrote:
>
>> On Tue, Apr 23, 2019 at 11:02 AM Jon Elson via cctalk <
>> cctalk at classiccmp.org> wrote:
>>
>>> Is the ROM totally bad, or just losing a few bits here and
>>> there? If the latter, you could probably read it out, figure
>>> out how the rows, columns and characters are mapped, and fix it.
>>>
>>
>> Considering that 925s are really common, and a replacement EPROM should be
>> easy to source and program, this sounds like an overly difficult approach
>> that will yield something different than what he wants.
>>
>
>The thought had crossed my mind, but only as a last resort.  I'm not
>entirely sure what the internal fault is, but the end result is two rows of
>every character have all bits stuck "on."  I've verified that the ROM
>addressing is correct and that there's nothing on the output side causing
>this behavior.  Patrick, thanks very much for offering to read the ROM!
>
>- Josh
>
>
>
>> Pat
>>
>