My OSI 610 build - Expansion for the OSI 600

[HigashiJun]

[rubber_jonnie]

This just arrived:

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Double sided 80 track Tandon, seems to work OK with my BBC B.

Will try it with the OSI later.

[stephen_usher]

[rubber_jonnie]

Seems to be working just fine with my BBC B too

[rubber_jonnie]

And it's working with the OSI too

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And here booting from a disk copied from Gotek to real FDD

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The drive has a head lift solenoid too, something I've never had in a 5.25" drive before, and since the OSI is expecting an 8" drive, it continually spins the disk, so lifting the heads and dropping only when needed is a definite bonus.

[stephen_usher]

[rubber_jonnie]

I'm jamming like it's 1979

[HigashiJun]

[rubber_jonnie]

Well the last couple of days have been a bit of a pain.

My C1P-MF (OSI 600+610 Board) started to do this intermittently:

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And slowly got worse until after a while that was all it would do. I spent a lot of time testing all the logic IC's and finding all were fine, pulling all the RAM bar the 2 video and 2 lower RAM ICs, then swapping them with each other to verify the RAM was good.

It didn't leave many options, but the CPU was showing signs of life at boot, but it wouldn't start. Surely the monitor ROM was fine? Nope it wasn't, as soon as I dropped in a replacement, it started running again, and after finally putting all the RAM back in, I got this:

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Now breathing a sigh of relief that it was something simple. I can reassemble it with the 610 board now and fingers crossed it'll be just fine.

[rubber_jonnie]

And just to annoy me even further, the FDD interface no longer works, even though the RAM upgrade does...