Computers with multiple (different) processors

[CatPix]

So, from a thread on Classing gaming, I just started to wonder : what computers, retro or modern (but more likely retro) include multiple processors, working together or as separate?

I'm thinking mostly about "all-purpose" processors, like the C128 that include a Z80 for CP/M compatibility (that is to say, I wouldn't count computers that use proccessors for something that is not related to computation - I wouldn't count the floppy drive 6502 in the C128D/cr as being part of the computer, for example. (tho thinking about it, such oddities are fun enough to be worth a mention here as well ). Multi-core systems (that use the same CPU multiple times) doesn't count. Unless they are retro ones, as they certainly are uncommon enough

 

I have three examples in mind, tho only one really get impressive IMO :

 

The Amstrad Mega PC :

Released in 1993 in Europe, it's simply a 80386 with a Megadrive built in, and using the same video output than the PC, which Amstrad provided with a 15Khtz compatible VGA display.

It does then count 3 processors, the 80386, a 68000 and a Z80.

It must be noted that both systems are totally separate; the PC doesn't have acess to the Megadrive side.

 

The Sega Teradrive :

released in 1991 in Japan, it's a 80286 with... a megadrive inside. Tho unlike the Amstrad Mega PC, it was actually possible to use the Megadrive hardware from the PC side, making possible to use the Teradrive as a kind of devkit. It failed hard, due to a high price and a very outdated CPU.

3 processors : 80286, 68000 and Z80

 

The Iskra Delta Triglav :

Released in then-Yugoslavia during the mid80's, this computer include a DEC J11 (PDP-11 CPU), a 80286 and a 68000, making in compatible with many popular systems of the time.

It's unclear if the 3 CPU work at the same time or if you have to select which "part" you want to boot.

 

[carlsson]

Would it have to be stock configuration? If not, the BBC Micro series supports Second Processor through external interface, and you can choose between 6502, Z80, NS32016 or 80186 I believe. In modern days, there even have been ARM7 second processor upgrades.

 

When it comes to a stock configuration, the SuperPET 9000 should count, having both a 6502 and a 6809. There were 3rd party upgrades to other PETs to give them 6809 support as well, but the SuperPET came with that configuration to start with.

[JamesD]

DEC Rainbow. Z80 and 8086
JVC HC 90/95: Z80 and Z180 (ok, so the Z180 just expands on the Z80)

The MSX Turbo R had Z80 and R800 (R800 is a really fast Z80 compatible)

There were a lot of CP/M expansions for machines but they didn't come standard.
Apple IIs had Z80, 6809, 68008, etc... cards and were probably the king of those kind of machines.
The Trackstar card added Apple II compatibility to PCs.

Macs had an Apple II card.


*edit*

FWIW, the Z180 supports additional instructions and you can write software for it that won't run on a Z80.
Not sure about the R800

Edited September 28, 2015 by JamesD

[roland p]

Megadrive/Genesis and the NeoGeo had a Z80 and a 68000.

[carlsson]

JamesD: It strikes me that the Basis 108, which is an Apple ][+ clone, indeed has an onboard Z80 so pretty much the Softcard built-in. So if not a regular A2 with additional expansion board qualifies, the clone should.

[Mr SQL]

The VIC-20 and the C64 do count for having a seperate processor in the 1541 floppy drive; you could offload code to that CPU and run it there - think there was about 2K of program space; significant potential for the coprocessor crunching a heavy duty algorythm.

 

Never saw it used except to play "drive music" though

[JamesD]

JamesD: It strikes me that the Basis 108, which is an Apple ][+ clone, indeed has an onboard Z80 so pretty much the Softcard built-in. So if not a regular A2 with additional expansion board qualifies, the clone should.

Excellent point. It seems to me there were several clones that had a Z80 on board.

I'm guessing they were actually the same motherboard as the Basis 108 but sold under any number of names.

 

 

[CatPix]

The VIC-20 and the C64 do count for having a seperate processor in the 1541 floppy drive; you could offload code to that CPU and run it there - think there was about 2K of program space; significant potential for the coprocessor crunching a heavy duty algorythm.

 

Never saw it used except to play "drive music" though

It's a bit of a tricky point... due the the odd nature of this link, I guess you could do the same thing between two computers - plus I mentionned the C128D because of the drive being encased in, so unlike the Vic-20/C64/C128, it's an "included" drive, the CPU is permanently there.

At best it could be fitted in the same category as the Z80 expansion carts for running CP/M.

Add-on boards does count tho I'm not going to be too picky about what does in and what doesn't ^^ it's one way like another to talk about odd, old and amazing hardware

Edited September 28, 2015 by CatPix

[Mr SQL]

It's a bit of a tricky point... due the the odd nature of this link, I guess you could do the same thing between two computers - plus I mentionned the C128D because of the drive being encased in, so unlike the Vic-20/C64/C128, it's an "included" drive, the CPU is permanently there.

At best it could be fitted in the same category as the Z80 expansion carts for running CP/M.

Add-on boards does count tho I'm not going to be too picky about what does in and what doesn't ^^ it's one way like another to talk about odd, old and amazing hardware

Alright, this is a cool topic I'll go with the SX-64 for having the 2nd CPU in the drive being built in:

http://www.theregister.co.uk/2008/01/20/tob_commodore_sx_64/

 

Add on boards seem like cheating since it's not an original or standard config, but with them we've got the Amiga (x86 board, Targa board, etc) original IBM (math co-processor socket) and every legacy console that has a modern flashcart with a CPU or a legacy cart with an extra processor chip.

[JamesD]

The Coleco Adam had a Z80 and a 6803 to run Adamnet. Each tape drive, the keyboard and add on drives also had 6803s.

So, an Adam with two internal tape drives had 5 CPUs.


The Thomson TO8 and TO8D had a 6809 and a 6803 for the keyboard

[Seob]

A pc with a 3DO blaster add-on card, turning a pc into a 3do system.

[carlsson]

Ideally, a machine with multiple CPU's should have at least some of the RAM shared, or some internal I/O bus so data can be moved between the two. Just plugging in a self-contained SBC on an expansion bus and reuse keyboard and at best video output, is not quite what I consider multiple CPU.

 

I saw Dave Dunfield got a CBM 8032 with a 3rd party Z80 card for CP/M, but it shouldn't qualify more than any genuine Apple ][ with similar card.

 

It strikes me that the Fujitsu FM-7 has dual 6809 CPUs, which is cool but not as cool as two different architectures at the same time.

[CatPix]

Ideally, a machine with multiple CPU's should have at least some of the RAM shared, or some internal I/O bus so data can be moved between the two. Just plugging in a self-contained SBC on an expansion bus and reuse keyboard and at best video output, is not quite what I consider multiple CPU.

This is why I'm looking for an infos about the Iskra Triglav - I assume the engineers managed to at least share RAM between the 3 CPUs to save on cost - RAM was expensive back then, and that was true even in the "eastern block".

 

And so far it's the only system mentionned here that have 3 CPU that are used as main processors

 

I don't think that the system could really use all 3 CPU at the same time - but even if it did, I doubt the systems used with the computer were able to use it, and sadly I think this beast is wa too rare to have even a small Slovenian fan-base doing demos on it, or just merely checking the innards of it.

[awhite2600]

There were a lot of CP/M expansions for machines but they didn't come standard.

Apple IIs had Z80, 6809, 68008, etc... cards and were probably the king of those kind of machines.

The Trackstar card added Apple II compatibility to PCs.

Macs had an Apple II card.

 

 

Was there a Z80 - CP/M card available for the original IBM PC?

[CatPix]

Why would there be? CP/M was originally written for Intel 8088 processors, and that's what is powering the early IBM PC.

I wonder tho if CP/M was working on 80286 CPUs and later ones, tho I believe at this point, CP/M was getting obsolete...

Edited September 29, 2015 by CatPix

[JamesD]

 

Was there a Z80 - CP/M card available for the original IBM PC?

I think the DEC Rainbow and Epson QX-16 had the Z80 built onto the motherboard.

I'm not sure if there was an ISA card back then but I know someone has built one since as a hobby project.

[JamesD]

Why would there be? CP/M was originally written for Intel 8088 processors, and that's what is powering the early IBM PC.

I wonder tho if CP/M was working on 80286 CPUs and later ones, tho I believe at this point, CP/M was getting obsolete...

CP/M was written at least 3 years before the 8088 existed.

It was written for the 8080 and then got adopted for the backwards compatible Z80.

 

CP/M 86 was written for the 8086 (hence the name) and 8088 after the 8080 version.

There is also a version for the 68000.

[Keatah]

Any games made for CP/M?

[CatPix]

Thanks for correcting me. Tho unless I'm wrong again, CP/M was available from the start for the original IBM PC, and so didn't need an add-on card - aside from one for boosting, it, but not for allowing a CP/M on it.

 

For games, I know there was at least some ASCII art based games, and probably text games on CP/M.

There is many games for the Amstrad PCW, probably the most successfull CP/M compatible machine sold, but I think those games more use the Amstrad software than the CP/M.. plus they would run only on a PCW, not on every CP/M machine.

Edited September 29, 2015 by CatPix

[JamesD]

Any games made for CP/M?

The lack of common graphics hardware pretty much prevented anything beyond Infocom.

The differing disk formats also hindered adoption by anyone that wanted to use copy protection.

[JamesD]

Thanks for correcting me. Tho unless I'm wrong again, CP/M was available from the start for the original IBM PC, and so didn't need an add-on card - aside from one for boosting, it, but not for allowing a CP/M on it.

 

For games, I know there was at least some ASCII art based games, and probably text games on CP/M.

There is many games for the Amstrad PCW, probably the most successfull CP/M compatible machine sold, but I think those games more use the Amstrad software than the CP/M.. plus they would run only on a PCW, not on every CP/M machine.

The 8086 is basically a 16 bit enhancement of an 8080.

I don't believe the 8086 runs 8080 code but it's very easy to port 8080 source to the 8086.

It's kinda like the 6809, it doesn't run 6800/6803/68hc11 binaries but you can reassemble the code for the 6809 with few changes.

Since MS-DOS is basically CP/M 86 the OS calls are pretty much the same as 8080/Z80 OS calls, maybe at different addresses.

 

Edited September 29, 2015 by JamesD

[carlsson]

Regarding the BBC Micro, it strikes me that the Master 512 model came pre-fitted with a co-processor board featuring a 80186 and 512K RAM. While still not being an integrated solution, since it was sold brand new with co-processor installed, it could be a candidate if not the regular BBC Micro with a Second processor connected to the Tube would. However just the fact that a computer would have a proprietary interface for externally connecting a different CPU (and turning the internal one into an I/O slave processor) is noteworthy for being a 1981 design aimed at schools, offices and upper class homes.

[Mr SQL]

The 8086 is basically a 16 bit enhancement of an 8080.

I don't believe the 8086 runs 8080 code but it's very easy to port 8080 source to the 8086.

It's kinda like the 6809, it doesn't run 6800/6803/68hc11 binaries but you can reassemble the code for the 6809 with few changes.

Since MS-DOS is basically CP/M 86 the OS calls are pretty much the same as 8080/Z80 OS calls, maybe at different addresses.

 

Agree the 8086 enhanced the 16-bit instruction set, but IMO the 8080 was already a 16-bit chip, just on an 8-bit bus like the 6809 for compatibility with existing 8-bit system architecture.

 

The 286 enhanced the 16-bit instruction set further while the 386 made the complete leap to 32-bit while still on a 16-bit bus, essentially providing enough 32-bit architecture to run most 32-bit intel apps we later ran on the 486 and pentium/586; you could run warp, NT, windows 95, office 2000, etc on a 386 (albiet horribly slowly).

[Mr SQL]

The four player X-Men arcade game really showed off what two 6809's could do

[+OLD CS1]

The four player X-Men arcade game really showed off what two 6809's could do

 

¿Que? This one?

 

https://en.wikipedia.org/wiki/X-Men_(1992_video_game)

"68000 (@ 16 MHz)

Z80 (@ 8 MHz)"