What system are these disks for? 6800 CPU, Flex OS. SWTPC 6800?

[krslam]

I found this binder of 5.25" disks in one of my boxes of misc stuff. Labels indicate that they are components of a BASIC editor/compiler system for a computer with a Motorola 6800 CPU running an operating system called FLEX (or maybe MINIFLEX). Not too many 6800 systems out there, the most prominent seems to be the SWTPC 6800.

 

Can anyone provide insight on what these are for?

 

[JamesD]

FLEX is like CP/M except for the 6800 machines.
There may have been other brands of FLEX machines, but SWTPC seems to be the most likely.
Looks like a BASIC interpreter and BASIC compiler.

This is complete speculation, but I'd guess the "Pre-compiler" scans for incompatibilities with the compiler. (unsupported commands, etc...)
That would probably be faster than waiting for the compiler to spit out an error after compiling 1000 lines of BASIC code.
Since the 6800 is slower than the 6801/6802/6803, a 1 MHz FLEX system would probably be slower than an MC-10, so such tool could save quite a bit of time.

[TheDash]

Interesting. You should try and back those up securely somehow, this would seem like something of a rarity.

 

You're right, most likely SWTPC. The Altair 680 also used the 6800 CPU, and much later on so did the Dragon 32 and Dragon 64. (or a slight variant of)

[krslam]

I don't have any system capable of reading them, unless maybe one of my old cp/m systems could do it using Uniform (or whatever the name of the multi-format reader program was). But, if I remember how Uniform works (it's been a looooong time), you have to know the disk layout beforehand: it can't figure it out on its own, and I don't have that info.

[JamesD]

You might see if the FLEX user group is interested in them. They might already have the software but you never know what else might be on those disks.
This site hasn't been updated in some time but I'm sure someone out there could read them.
http://www.flexusergroup.com/flexusergroup/fug1.htm

FWIW, there was also a version of FLEX for the 6809, but the CPUs aren't compatible and the reference to 6800 on the one disk indicates these were for the earlier CPU.

[deramp5113]

Hello, I’m waking up this old thread in case you still have these disks. I recently restored a SWTPC 6800 and have MiniFLEX running on it. As part of this, I created utilities for archiving and restoring MiniFLEX disks to/from a PC. See https://deramp.com/downloads/swtpc/software/FLEX/FLEX 1.0 (MiniFLEX)

 

If you still have the disks, I’d like to archive them for the 6800/FLEX community. There are very few MiniFLEX disks archived and these would be a great addition.

 

Thanks!

 

Mike D.

Edited April 9, 2022 by deramp5113

[krslam]

I still have them, but finding the binder might take a bit.  I have no idea if they're still readable but I'll post here when I find them.  Where are you located?

[deramp5113]

That’s awesome! MiniFLEX was basically lost until a hobbyist in Belgium contacted me a few months ago with original disks that he was attempting to archive. He had tried with ImageDisk, CryoFlux, etc., but was never able to then create a disk that actually booted from the disk images he captured. You’ll find this is true of most every MiniFLEX disk image you might find on the Internet - the image is actually corrupt.

 

The problem is that TSC and SWTPC used a disk layout with just a two byte post index gap. This gap is too short for the disk controller ICs in most PCs to be able to read the first physical sector after the index hole. The original controller IC used in the SWTPC 6800 worked (the FD1771), but PCs cannot not properly read the disks.

 

I wrote utilities to archive and restore the disks using the actual SWTPC 6800 and an XMODEM serial link to a PC. I would love to archive your disks for the community. I’m in the Dallas, Texas area. You can reach me for details using deramp5113 followed by ASCII 0x40 then the yahoo domain name.
 

Mike