S-100 systems

[Sharkonwheels]

anyone got an extra working chassis? Empty is fine.
I don;t need an unobtainium Altair or Imsai!! Just something
that works, ready to take cards.

Also, some background info would help - I've never done S-100.

Are the boot floppies tied to the kind of FDC controller?
I understand you need to have z80 for z80, 8080 for 8080, but I assume the format of the floppies is tied to the FDC type, correct?

So I'd want to lok for a FDC that has boot floppy images available somewhere?
I want to stick with 5.25" FD's - I really don't feel like hunting down 8" stuff!


Tony

 

[chuckcmagee]

I assume you are talking CP/M. As we can tell, each version of CP/M was totally tied to the FDC, and all the rest of the hardware. I owned a Vector Graphics 1 in 1978. As I recall, I snagged a Cromemco FDC and some 8" floppies, it was all totally related to your actual hardware. The Northstar Horizon stuff wouldn't even get off the ground, etc.

Oh, come on. I just loved the "swish swish swish" as those 8" monsters started turning. The noise, of course, was the media rubbing inside. Yes indeed, CLUNK, swish swish, CLUNK, etc. The heads were really noisy too.

 

[Sharkonwheels]

At first, I didn;t know where to start the thread: Here, because I'm interested in CP/M specifically, or the S-100 forum!

Yeah, so what's that mean to me? What do I have to go get? A complete 1-brand system? Like all Cromemco, for example, and then get Cromemco boot disks?

...Sounds like it's going to be a difficult, expensive proposition, with LOTS of opportunity for learning!


Tony

 

[Terry Yager]

If you just want to start with a bare board with p.s. & mainframe, I have one you can get for the same price Erik charged me for it -- shipping cost only. Pm me...

--T

 

[Terry Yager]

Are the boot floppies tied to the kind of FDC controller?
I understand you need to have z80 for z80, 8080 for 8080, but I assume the format of the floppies is tied to the FDC type, correct?

So I'd want to lok for a FDC that has boot floppy images available somewhere?
I want to stick with 5.25" FD's - I really don't feel like hunting down 8" stuff!


Tony

Now for the good stuff...

The boot floppies are somewhat tied to the type of controller at the bare-metal level, since different controllers have different registers, command sets, I/O port addresses, etc. One company's controller won't boot from another type controller's software (unless it's a close clone).

The format of the floppies is not completely tied to the hardware, except for some restrictions on what kind of media the FDC can read & write to. The (high-level) format of the disks are determined by the Operating System, or more precisely, the BIOS. Under CP/M, there are as many different formats as there are different hardware to run 'em. The difference between 8080 & Z80 boot code is not hard-wired to the controller chip, but to the boot-ROM found on most floppy disk controller boards. Some of them are written in (optimized) Z80 code, which won't be understood by an 8080, but the Z80 code is backwards-compatible with the 8080, so a Z80 can run 8080 code.

If you're in the market for an S-100 FDC board, try to obtain one of the more popular ones, like a DiskJockey, as the chances of finding compatible software are much better.

--T

 

[Sharkonwheels]

Yeah, CP/M.

So, doesn't matter what CPU card, or RAM cards, I pop in that S-100 bus, right?

Just gotta find a FDC controller with the correct CP/M floppies for it, correct?


Tony

 

[chuckcmagee]

As far as I can remember, that's correct. I remember pulling out an 8080a board and sticking in a Cromemco ZPU card. The "special stuff" is more related to the I/O boards. And I'm close to useless on the RAM boards. I went with static ram boards when I was doing it. Don't remember the status of drams around then (1979-1980). What I'm getting at with all that is not sure if you could use dynamic ram boards or not or if they even existed then. I do KNOW don't run the computer with the cover off for more than a few minutes. Static rams get very hot VERY FAST. Like "burn your finger" hot.

 

[nige the hippy]

My 16K (64 chips!) static ram boards have 3 separate 1A regulators on there just to supply the current required by the chips, It's the equivalent power to a small soldering iron.

PS I've slightly bottled it on my S100 system, after the floppy board smoked a protection resistor on the 5v rail. There's a few quirks to it, and I've still to get to grips with it, and life won't let me get on with the fun stuff!

like i've just sold my house, and the little lead roof over the bay window slipped off and let the last storm in, so I've been out there replacing the roof... anyway had time to replace the switch on the phillips 2000C, so I'm posting another thread, asking about CPM disks and the specifics....