Mega ST video output oddity

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exxos
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Re: Mega ST video output oddity

Post by exxos » Sat May 26, 2018 10:20 am

You not simply got some bad ROMs or bad RAM have you ? What ROM's exactly do you have ? Some brands like Texas cause odd issues, nobody knows why.
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Atarian Computing
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Re: Mega ST video output oddity

Post by Atarian Computing » Sat May 26, 2018 10:26 am

I know the roms are fine as they are my test roms. But could be that they might not work properly on this particular unit. I believe I've tried different ones but since I have so many projects I'll double check. I'll test the RAM too. Thanks.

czietz
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Re: Mega ST video output oddity

Post by czietz » Sat May 26, 2018 10:47 am

RAM can be tested with the diagnostic cartridge. ROM checksums can also be tested with the diagnostic cartridge.

I assume your test ROMs are of the two chip variety. Is the Mega ST mainboard in question properly set to two chip ROMs, then?

Atarian Computing
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Re: Mega ST video output oddity

Post by Atarian Computing » Sat May 26, 2018 11:13 am

czietz wrote:
Sat May 26, 2018 10:47 am
RAM can be tested with the diagnostic cartridge. ROM checksums can also be tested with the diagnostic cartridge.

I assume your test ROMs are of the two chip variety. Is the Mega ST mainboard in question properly set to two chip ROMs, then?
Whale oil beef hooked! That was it. Ran checksum test and it gave errors. That was a 32 pin rom on an adapter that works on every other ST here. Put in a mask rom set and it works. Weird. Will need to investigate further. Thanks!

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