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What is the best CP/M machine and why?

For example, I have an Amstrad "Joyce" word processor, but it has 512K of RAM and high-resolution graphics.

That's the one I have, didn't know it was called a "Joyce!" The screen is very nice, lots of RAM, keyboard is decent, just by default there's nothing to plug in except a printer. I really want to build at least a serial adapter, if not a full blown expansion converter.
 
That's the one I have, didn't know it was called a "Joyce!" The screen is very nice, lots of RAM, keyboard is decent, just by default there's nothing to plug in except a printer. I really want to build at least a serial adapter, if not a full blown expansion converter.

There was a serial option available, but it should be simple to pretty much build whatever you want, given that there is plenty of information (maybe still) out there.
 
For retro computers, I would have to say that the 'best' CP/M machines are probably the Z80-based Altos units. Fantastic hardware; I had an ACS8000-series with twin 8 inch drives that as far as I know is still running for the person who got it from me; codeman just sold a 580-10 on eBay that boots up to three-user MP/M from hard disk (I'm glad he got a fairly reasonable price for it, too).

The TRS-80 Model II would qualify if only counting the hardware capabilities, but as I recall the major CP/Ms for it weren't exceptionally reliable. And the 'cost-reduced' Model 12 has some odd issues to keep it out of the running.

If you're interested in the most floppy formats supported, then the Montezuma Micro CP/M for the M4 is nice. The Model 4's performance is a bit less than what the Model II could deliver, though, and there is the bit with the lack of some keys on the M4 (hey, I am an M4 junkie, but I vastly prefer LS-DOS to CP/M for my retrocomputing! And now that I'm used to having some of those characters on my keyboard the lack of them on the M4 is noticeable.).

Now, if you want the retro CP/M feel with modern-retro hardware, you really should look into building an N8VEM Z80 system. If emulated hardware is enough, codeman's z-80 sim is quite nice, on pretty good hardware (I just bought a Duinomite from codeman through eBay.... just wish the TRS-80 sim code was public :).....).
 
May seem boring but you could theoretically get an IBM 5150 or 5160 and run cpm-86. Then at least you have dos also and all the nice compatibility and cheapness of the x86 market.

Theoretically? I have a copy of CP/M-86 on a shelf in an IBM binder, just like the early DOS offerings. IBM offered it as an option along with DOS and UCSD P-system.

On another note, there is a version out there that has been edited to support HD floppies and some other goodness. I have it installed on a DECpc with a 100MHz 486.

On a related note, what is the latest computer that anyone has installed CP/M-86 on? I couldn'tget it to boot on anything later that that 486 with an ISA bus.
 
I have both 8256 and 8512 Amstrad "Joyce" machines and an AMX mouse. The interface slips over the edge connector. The 8256 has twin drives, one of which is double sided. I thought I'd get it out and have a play and I think it is very slow. You can see it updating the screen a character at a time. I mean, you can follow the screen update horizontally with your eyes which is to my mind really terrible. In the UK they are still cheap. I think I paid £15 each, both with printers and disks. The keyboards are awful, I have to say. Very light and plasicy, but usable.

It's probably worth fitting a pair of 800k 3" floppies instead of the horrid Amstard drives, but it really needs a hard drive and a speed boost.

To answer another question, I will use it for development. The M4 already has C compilers installed on its Cheapo IDE widget and I am looking to build a vi clone for it (an early version of stevie which I am going to port to CP/M). Missing keys on the M4 keyboard (tab, escape, [] {} etc) are a pain but as I said I have it connected to a dumb terminal. The worst thing is having to exit source code with WordStar. Slow and awkward for me as I don't know the keystrokes. I can see its a powerful word processor otherwise.

Naturally this version of vi will be released with source and credits, but I have a long way to go yet.
 
On a related note, what is the latest computer that anyone has installed CP/M-86 on? I couldn'tget it to boot on anything later that that 486 with an ISA bus.

How about a quad-core AMD64 system? You can do it with Virtualbox. See info here. I believe that there's someone who got it running under QEMU also.

If you want to work in native mode and can keep your CBIOS interface down to PC BIOS calls, there's no good reason that you can't run it on the most bleeding-edge x86 hardware. You'll probably have to start with the OEM kit, though.
 
I've used a good number of CP/M-80 machines in my time and I still have a few. One machine I used to use and enjoy working on was the NCR Decision Mate V but I've never owned one.

The build quality is very high. Much better than most. It has pixel graphics, a solid expansion system, good floppy capacity and a hard disk.

The only downer is that they are rare and expensive but great if you can find one.


Cheers,

Andy.
 
I have both 8256 and 8512 Amstrad "Joyce" machines and an AMX mouse. The interface slips over the edge connector. The 8256 has twin drives, one of which is double sided. I thought I'd get it out and have a play and I think it is very slow. You can see it updating the screen a character at a time. I mean, you can follow the screen update horizontally with your eyes which is to my mind really terrible.
The Amstrads don't have any text-mode in hardware, so every character has to be drawn as bitmap graphics. It's a lot more flexible but the tradeoff is as you mention; display update speed.

When not outputing to the screen, it should be as fast as any other 4MHz Z80 machine.
 
The Amstrads don't have any text-mode in hardware, so every character has to be drawn as bitmap graphics. It's a lot more flexible but the tradeoff is as you mention; display update speed.

When not outputing to the screen, it should be as fast as any other 4MHz Z80 machine.

I suppose the other tradeoff (for back then) would be greater need for RAM vs the CRTC/Character ROM route.
 
I suppose the other tradeoff (for back then) would be greater need for RAM vs the CRTC/Character ROM route.

It's actually what you want for Wapro mode--I suspect that the ability to have several fonts on the screen was viewed as a necessity. I don't know if it was done, but prop spacing would have been possible. Speaking of which, does anyone know of any real systems that used the Intel character controller chip that varied the dot clock to change the width of individual characters?
 
Good point about the screen! As far as I can see, the bitmap was not used for multiple fonts in Locoscript (the WP that came with it). It just acts like a normal character based interface, only slower.

There were some games for it, and also some desktops (really, "program launchers") that used the mouse. Don't forget these machines had 256k RAM (512 on the 8512) which were used for a RAMdisk in CP/M but when running directly (without CP/M as Locoscript does) you can page it.

Interesting factoid: the screen implements "roller RAM" which is a lookup table that tells you where each line begins. You can get some interesting effects (other than scrolling) by manipulating this table.
 
I liked the BASIS-108 back in the day. That was the Apple clone in a box you could jump up and down on, with 128K RAM and Z80 built-in. Two floppy drives. Could handle both Apple and CP/M disks. Came with CP/M Plus and full DRI documentation. Separate low-profile full keyboard. I wish I had one of those computers but I was too late when they were disposed of. An Apple and a CP/M 3 computer in one nice box made a flexible useful system. I used one for a satellite tracking setup I wrote, it ran continuously for about ten years.
 
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Tor indirectly brings up another decent CP/M system: an Apple II with a CP/M softcard. Not the fastest, but it does run CP/M as well as Apple software! Don't expect to directly exchange disks with anything other than more Apple II CP/M users, though.
 
Tor indirectly brings up another decent CP/M system: an Apple II with a CP/M softcard. Not the fastest, but it does run CP/M as well as Apple software! Don't expect to directly exchange disks with anything other than more Apple II CP/M users, though.

Dig up a Micro Solutions MatchPoint PC card and you can format, read and write those on a PC using both Apple DOS and CP/M--MS included a copy of Uniform tailored to the card. The USPS bought those by the caselot.
 
If you want a very special CP/M machine of very good hardware design and quality, try to get Olivetti ETV 250/300/350. But for 300/350 take care that you also get the fitting typewriter from the Olivetti ET 22x/11x series with the optional serial interface as these act as keyboard and daisywheel printer for the ETV system. The ETV 250 has everything included. ETV 250/350 are 3,5 inch disk based and 300 is 5,25 inch. But all of these ETV systems are a 'bit' unusual... :)

Another thing I still remember as an interesting CP/M machine was the Olympia Boss. See klick. Olivetti also provided a Z80 CP/M card for their famous M24 PC (AT&T 6300, Xerox 6060).
 
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