[Coco] [HW] Coco 3 video output corrupt when using cart port

[Brian Sturk]

Hi Robert,

Thanks for the ideas.  The fringing seems to be on a 40 columns.
I sent an email out a little while ago thinking a warm reset helps but 
not it's not exhibiting the issue anymore.  I wonder if it's thermal 
related (i.e. being on for a certain amount of time?).

I'll try and narrow something down...

~telengard
> Brian Sturk wrote:
>
>>   On a black screen I can see hints of orange and blue.  It's almost 
>> like random repainting of the screen *and* the magnetic field 
>> effect.  Definitely weird.
>>
>> thanks for the help, I'll report back,
>> ~telengard
>>
>
> As Tim suggested, re-seating all socketed chips is a good idea even if 
> it does not help with this problem. Tandy did not use gold plated 
> contacts so a fresh surface can't hurt and could help.
>
> The orange and blue, is that fringing around text with a 40 or 80 
> column screen? If so, it is artifact colors typical of composite 
> video. Some screen colors will make the effect worse than others. 
> There is only one way to get rid of it completely and that is by 
> patching Basic.
> If this is the source of your colors, I'd suggest using a 40 column 
> screen with a white background and black letters. Enter
> WIDTH40
> CLS5
>
> If the orange and blue is artifacts and you get a disk system to make 
> it easy to SAVE and RUN programs, the following will turn off the 
> color burst signal and remove artifacts.
>
> 10 POKE&HE033,16:REM width 32 screen
> 20 POKE&HE03C,19:REM width 40 screen
> 30 POKE&HE045,19:REM width 80 screen
>
>
> -- 
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco


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