BIOS Address (A13-A15) & Missing Every Other Character

GadgetUK

Ace Ghost Pilot
Joined
Sep 27, 2013
Posts
1,323
Has anyone seen this behaviour before on an MVS?

The error is BIOS Address A13 - A15. The ROM has good connectivity to the CPU. I am speculating the CPU might be the problem.

IMG_4805.JPG
 

gusmoney

Unsure if You Asked, For a custom Rank, But Hell,
10 Year Member
Joined
Nov 3, 2014
Posts
1,851
My MVS Bios has similar issues in my single-slot MV-1A:

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I am not sure of the cause.
 
Last edited:

Dropwire

Kuroko's Training Dummy
Joined
Jul 27, 2018
Posts
75
Has anyone seen this behaviour before on an MVS?

The error is BIOS Address A13 - A15. The ROM has good connectivity to the CPU. I am speculating the CPU might be the problem.

View attachment 51540

Just some questions, apologies if they seem silly.

- Is the Address error the same after a few reboots ? (i.e, always A13 - A15)
- What is the Error when using the stock Bios? -or- Uni-Bios?
- Are you testing with or without the test cart in the slot?

While I did not have the same exact error, I have seen garbage on screen before using the test bios and had a feeling there may have been a bad connection or cold solder joint. And while not recommended I did use my rework stations hot air tool to apply heat around the 68k / C1 / and RAM while the MVS was powered on, and I must have been lucky because it cleared up. But I don't recommend this since solder may flow/bridge a connection and while the board is powered up it could spell trouble. But hey I live dangerously sometimes. :loco:
 
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