DragonMMC Out of Memory with CoCoVGA

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KenH
Posts: 182
Joined: Fri Oct 12, 2012 9:50 am

DragonMMC Out of Memory with CoCoVGA

Post by KenH »

Has anyone successfully used the DragonMMC on a Dragon with CoCoVGA installed?
Although I can CAT and MLOAD and MDISKI OK, trying to run the Explorer yields ?OM Error.
Print MEM shows just 8K free on my Dragon 64.
Upgrading (and downgrading) of the DMMC firmware doesn't seem to help.

The Dragon works perfectly when used with the CoCoSDC, so this is not a RAM issue.
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dublevay
Posts: 107
Joined: Wed Jan 23, 2019 3:41 pm

Re: DragonMMC Out of Memory with CoCoVGA

Post by dublevay »

The MMC clock is wrong, which suggests the back up battery is dead - but I don't know if that would cause this ?OM ERROR.
KenH
Posts: 182
Joined: Fri Oct 12, 2012 9:50 am

Re: DragonMMC Out of Memory with CoCoVGA

Post by KenH »

dublevay wrote: Tue Sep 20, 2022 6:02 pm The MMC clock is wrong, which suggests the back up battery is dead - but I don't know if that would cause this ?OM ERROR.
Indeed I had a bad battery, but I get the same memory problems with the clock properly set.
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This does not seem to be a RAM issue, as when I unplug the MMC everything seems to work as expected:
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Alastair
Posts: 650
Joined: Fri Jul 18, 2008 11:33 pm

Re: DragonMMC Out of Memory with CoCoVGA

Post by Alastair »

Perhaps the configuration settings or autoexec file have become corrupt due to the battery problem.
prime
Posts: 264
Joined: Fri Apr 10, 2009 1:40 am

Re: DragonMMC Out of Memory with CoCoVGA

Post by prime »

I've seen this with DragonMMC when the edge connector is dirty / not making proper contact with the socket in the Dragon.

Try giving both a clean and see if things improve.

Cheers.

Phill.
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