Author Topic: MP1 Composite question  (Read 507 times)

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Offline arnoldemu

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Re: MP1 Composite question
« Reply #10 on: 10:21, 04 April 17 »
That effect with the black bar isn't something the modulator could do. It sounds like you have issues with either the Gate array or the CRTC Chip.

Bryce.
The black bar is probably the vblank normally triggered by vsync.

On the CPC monitor the screen can be adjusted with the vhold, not sure what is needed on mp1.

It could be:
- a dodgy link on the PCB causing it use 60hz instead of 50hz. Does it change when you run a game?

- the sync is going from the crtc to the gate-array, could be either a problem with crtc, or gate-array or a bad connection on the video out of the cpc.


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Offline Homr836

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Re: MP1 Composite question
« Reply #11 on: 21:51, 04 April 17 »
Hi Arnold,

Like I said, I tried to run a game but the tape drive belt is a bit sloppy and I can't find my HxC anywhere in the loft.

I would say the wiring is at fault as I wasn't at my workbench when I replaced the cable to the MP1 (I was sat on the living room floor), and until I can run a game, I can't specify further.

Thank you both for your inputs though  :)
Regards,

Homr

Offline Homr836

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Re: MP1 Composite question
« Reply #12 on: 23:15, 21 April 17 »
Arnold,

I've managed to get the tape drive working and I get this



But when I select play and cut to the game, I get this



The bottom half of the screen disappears. I do have a scart cable somewhere, which I'm trying to find so I can eliminate the CPC so watch this space..............

Regards,

Homr