[Coco] Fixing my "F" board TDP-100...

[Al Hartman]

There re no joysticks attached. It's just the computer alone. I can try 
swapping the keyboard later with the one from the "E" board Coco, but 
there's not much to go wrong in a keyboard. I tried swapping the two 6821 
chips because I thought maybe they were bad.

The only chip I have not swapped is the VDG chip.

-[ Al ]-

-----Original Message----- 
From: Steve Batson

Can you swap the whole keyboard? Also, and I may be remembering this wrong, 
but seemed like faulty Joysticks can cause strange things to happen. Like 
the button pressed and you couldn't type. Maybe bad joystick or port

Steve Batson
Batson Photography
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> On Apr 20, 2015, at 7:46 AM, Al Hartman <alhartman6 at optonline.net> wrote:
>
> Came back from the hospital, and had a little energy...
>
> - I swapped the 6809EP chip, no change.
>
> - I swapped the RAM and now it boots to a good screen. But, I can’t type: 
> “? Mem” The computer clears the screen, and prints a “.” when I press the 
> “?”. If I type “PRINT”, IT COMES OUT “PRININT”.
>
> - I resat the keyboard connector (HJL keyboard), no change.
>
> - I swapped the SAM, no change.
>
> - I swapped both 6821 chips, no change.
>
> - If I plug in the RAM CHECKER cartridge, the screen goes into a graphics 
> mode, and displays junk.
>
> - The only chip I haven’t changed is the 6847 VDG. I didn’t have a spare, 
> I need one for the Dragon (I thought I had one), so I ordered two on eBay, 
> and two sets of 64k RAM. I need one for a Coco 2 here, and one for the 
> Dragon. Once I have this working, I’ll test every chip I have and 
> hopefully, I’ll have enough chips to upgrade the “E” board Coco.
>
> It may be that I just need to buy an “F” board Coco and swap the logic 
> board in...
>
> -[ Al ]-
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