Actually - in the Sharp advertisement, they "name drop" Microsoft explicitly - so perhaps I misspoke in mentioning IBM's PC-DOS (but if we're making disks, I'd just try to have both ready just in case). I've not yet opened the external drive enclosure to investigate specific model/parts (I'm very curious about the controller and how it differs from the standard IBM ISA disk drive controller, but there is some difference since a 37-pin drive that worked in my 5150 wouldn't work with this Sharp).
I'm generally clumsy with hardware (in a "oops, dropped that cup of screws all onto the board while it was powered on" kind of way- maybe not that bad, but enough to know to go slow and enjoy what I have for a bit first, before I open it and screw it all up; my biggest regret was on a 1996 ThinkPad - it was running OS/2 just fine on a handsome solid state proxy IDE, but I didn't like the color fade on the bezel of the CD-ROM, and just "had" to going back in and address that - and that system has never booted since). Point being, I'd like to try some disk first before tinkering inside this drive enclosure. The host system is this: < https://voidstar.blog/sharp-pc-5000 > which I hope to finally prepare a broader video about it before the end of this year. And - oh, depending on the controller, we might be able to adapt a 720K drive onto it? I see, that'd be an interesting mod. But not yet - gotta try as-is first. This Sharp is a tad confusing (or it was to me). I had the impression that the DOS was built into the ROM - but no, it's actually copied/placed onto each of the bubble memory cartridges, so it is always "booting" to DOS like a "normal" system. Also in my notes - i may have to revise on if the BASIC is built-in or not. It's "built into" one of the ROM cartridges you place into the bottom of the system. So it's not technically a "boot to BASIC" system either (I'm not sure if that excused them from Microsoft licensing in some way??). Or actually - I'll have to unplug that cartridge and remind myself what all the system can do on its own (as I recall, in doing so, it does "boot" into a self-running demo mode). I hope it's not too much of a lost cause - I think I do recall coming across an article that mentioned that the system could be booted from the external floppy. And if it could miraculously boot to something like DOS 3.2 - well, I can't think of any program of that era that would play nice with an 8 row screen. But that's the goal here, to just see what happens. In the worse case, this will mean I can make a backup of all the content of these bubble memory cartridges content, just in case they start to deteriorate in some way (that said - since it does have a "built in" BASIC, I suppose technically I can do a BASIC that invokes the serial port and I could export every file that way; thumbing through the manual it does have some keywords that might accommodate that -- I'll save that as a last resort). And Thank You Travis, I'll be in contact!! -Steve On Tue, Sep 24, 2024 at 10:00 PM Fred Cisin via cctalk < [email protected]> wrote: > On Tue, 24 Sep 2024, Steve Lewis via cctalk wrote: > > But does anyone here in the States happen to have a stack of known-good > > 5.25 disks they don't want anymore? > > Sorry, not right now > > > > have a drive for an old system that currently uses bubble memory > > cartridges to boot to PC-DOS 2.0, and so we'd like to see if (using > > these external drives) it could also boot to a (confirmed legit) image > > of IBM PC-DOS (and/or very early Microsoft DOS). Or, do we still need > > some kind of proprietary Sharp DOS image? (in which case, extra blank > > disk would be good, as I think there are tools on these bubble memory > > cartridges to initialize disks accordingly). > > What kind of drive is it? > > If it boots to PC-DOS 2.00, not MS-DOS 2.00, then it is not some kind of > proprietary Sharp DOS. > > If Sharp, or whoever made your machine, ever did provide their own > customized MS-DOS, it was likely to be versions 1.25, 2.11, or 3.31 > Many OEMs added 3.5 support in MS-DOS 2.00 amd 2.11. PC-DOS didn't > support 720K until PC-DOS 3.20, and 1.4M 2ith 3.30 > > > > (did anyone ever make a "USB-to-5.25" drive? I have a couple 3.5 > > versions of those - maybe the power to motor the 5.25 is too much for > > USB? :D ). > > a few minor problems, in addition to power (easily solved with a external > brick) > There did once exist a few, but they are VERY rare. > There were also some with cooperative circuitry, that had an unmodified > 3.5 drive in them that could be recabled to 5.25. > (still a few gotchas to deal with, such as "Disk changed" signal) > > > But, if you have a functioning 720K 3.5, you could put early 5.25 DOS on > it, even down to 1.00, and just use the first 40 tracks. In the days > before the 5170, the machine didn't really care, > > -- > Grumpy Ol' Fred [email protected] >
