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9ecc53ce | 1 years ago (raw) | export | reply | flag 
 This computer is not booting from disks and is stumping me a bit more than I thought. This is a Jonos Escort, a *very* early 3.5" portable CP/M Z80 system, and from my understanding is not common. I've also never used a CP/M system, so I'm not quite sure if I'm at fault or it is just having an issue.

This has Sony OA-D32V drives in it, I roughly serviced the top drive and can see the disk moving. The system also trys to load disks but never finishes. Are there any gotchas for booting CP/M?

https://dialup.space/system/media_attachments/files/111/157/358/292/825/231/original/238cca15eebf8a2d.png
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Pawlicker 🐾😹 | 1 years ago (raw) | root | parent | reply | flag 
 @56923621 Try a FDD emulator to rule any out oddball formats (had to do this with N88-BASIC due to it mixing FM and MFM sectors for boot rendering nothing able to make disks.)
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FozzTexx | 1 years ago (raw) | root | parent | reply | flag 
 @56923621 Are they single sided drives? Weird single sided 40 track drives?
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9ecc53ce | 1 years ago (raw) | root | parent | reply | flag 
 It ended up being the drives! I swapped in a known repaired drive from my HP 9121 and it worked first try!

I put some more time into the original drives after and was able to get both of them to read. I still need to do a proper teardown and deep clean on them, but at least I know they will work.

https://dialup.space/system/media_attachments/files/111/162/513/851/932/475/original/de818d5b5a145953.png