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View Full Version : Osborne Vixen video problem



snuci
April 17th, 2014, 05:27 AM
I just got a Vixen that had video problems. I looked over the schematics at BitSavers... and it's completely different than the one I have. My boards match the picture on Bitsavers but the schematics don't match that one.

It first exhibited no video but I was able to make adjustments to get some output so I know the screen is okay but it's crazy output that needs to be adjusted. I also tried to connect a video monitor with composite but I get no output there. Somewhere I read there was an external monitor jumper but my boards (main board and I/O board) don't have any jumpers.

I read the Video (1.10), Monitor (1.01 08bd) and Character (1.00L) ROMs and the Video and Monitor ROMs appear to be different than the ones on Bitsavers since those may be newer. The chips are simple AM2732s and I'm wondering if their integrity has been compromised. I also downloaded MESS Vixen ROMs and they are also different but very close to the Bitsavers ROMs. Would it be a bad idea to rewrite my ROMs with the Bitsaver versions and try that?

Any help is much appreciated.