Author Topic: The Commodore 256  (Read 3785 times)

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Offline mwithings

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The Commodore 256
« on: June 10, 2018, 08:07:31 am »
The 65C816 feels a little weird from a "what Commodore would do" perspective, but seems like an interesting project nonetheless:

http://blog.snapeda.com/2018/06/06/building-the-commodore-computer-that-should-have-existed-an-interview-with-stefany-allaire/
 

Online Alex Eisenhut

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Re: The Commodore 256
« Reply #1 on: June 10, 2018, 12:40:13 pm »
 

Offline guenthert

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Re: The Commodore 256
« Reply #2 on: September 12, 2018, 05:51:00 pm »
Well, three years earlier, people would have killed to get their hands on a Apple IIGS, but in 1986 Atari ST and Comodore Amiga were out and the GS pales in comparison.  Pity really, the Woz dream machine deserved more interest.  Its really a good example of why time-to-market matters.
 

Online Alex Eisenhut

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Re: The Commodore 256
« Reply #3 on: September 14, 2018, 11:42:11 am »
Well, three years earlier, people would have killed to get their hands on a Apple IIGS, but in 1986 Atari ST and Comodore Amiga were out and the GS pales in comparison.  Pity really, the Woz dream machine deserved more interest.  Its really a good example of why time-to-market matters.

You sure?

https://youtu.be/oipg9cM6rqw?t=96

 

Offline Bashstreet

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Re: The Commodore 256
« Reply #4 on: September 16, 2018, 09:59:18 pm »
Well, three years earlier, people would have killed to get their hands on a Apple IIGS, but in 1986 Atari ST and Comodore Amiga were out and the GS pales in comparison.  Pity really, the Woz dream machine deserved more interest.  Its really a good example of why time-to-market matters.

You sure?

https://youtu.be/oipg9cM6rqw?t=96

There is a reason why for every 1 Apple IIGS 6 Amiga's were sold.
 

Offline Rasz

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Re: The Commodore 256
« Reply #5 on: September 23, 2018, 06:16:27 am »
Well, three years earlier, people would have killed to get their hands on a Apple IIGS, but in 1986 Atari ST and Comodore Amiga were out and the GS pales in comparison.  Pity really, the Woz dream machine deserved more interest.  Its really a good example of why time-to-market matters.

SNES was 1990 and was better than A500, ST was a sad joke. The trick at the time was strong Video processor, handling sprites and special effects in hardware without cpu. 68000 was a pretty bad cpu, half 65C816 performance at twice the clock.
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Offline ebastler

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Re: The Commodore 256
« Reply #6 on: September 23, 2018, 07:19:14 am »
SNES was 1990 and was better than A500, ST was a sad joke.
68000 was a pretty bad cpu, half 65C816 performance at twice the clock.



 ;)
 

Offline Bashstreet

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Re: The Commodore 256
« Reply #7 on: September 23, 2018, 07:57:14 am »
Well, three years earlier, people would have killed to get their hands on a Apple IIGS, but in 1986 Atari ST and Comodore Amiga were out and the GS pales in comparison.  Pity really, the Woz dream machine deserved more interest.  Its really a good example of why time-to-market matters.

SNES was 1990 and was better than A500, ST was a sad joke. The trick at the time was strong Video processor, handling sprites and special effects in hardware without cpu. 68000 was a pretty bad cpu, half 65C816 performance at twice the clock.

Not sure what a console gaming system has to do with a computer systems.  :-//
 

Offline Rasz

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Re: The Commodore 256
« Reply #8 on: September 23, 2018, 08:55:08 am »
Well, three years earlier, people would have killed to get their hands on a Apple IIGS, but in 1986 Atari ST and Comodore Amiga were out and the GS pales in comparison.  Pity really, the Woz dream machine deserved more interest.  Its really a good example of why time-to-market matters.

SNES was 1990 and was better than A500, ST was a sad joke. The trick at the time was strong Video processor, handling sprites and special effects in hardware without cpu. 68000 was a pretty bad cpu, half 65C816 performance at twice the clock.

Not sure what a console gaming system has to do with a computer systems.  :-//

SNES is a living proof 65C816 was a good processor.
Remember Wolfenstein 3D on Amiga? Atari ST? right.
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Offline ebastler

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Re: The Commodore 256
« Reply #9 on: September 23, 2018, 05:46:16 pm »
SNES is a living proof 65C816 was a good processor.
Remember Wolfenstein 3D on Amiga? Atari ST? right.

I think you are mixing up video processor performance with the CPU here. (And you stated in your earlier post that the video processor was the SNES' strength.)
 

Offline Rasz

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Re: The Commodore 256
« Reply #10 on: September 24, 2018, 03:34:59 am »
SNES is a living proof 65C816 was a good processor.
Remember Wolfenstein 3D on Amiga? Atari ST? right.

I think you are mixing up video processor performance with the CPU here.

Wolfenstein 3D rides on cpu power alone. IIgs has no sprites/blitter, still runs the game great. Modern ST ports do 1/2 the framerate on 520ST, Amiga is even worse.

And you stated in your earlier post that the video processor was the SNES' strength.

Video chip was what made or broke 8-16bit platforms in general due to anemic CPUs of the era.
65C816 Amiga would kick ass just as well, and made Commodore more money.
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Offline Bashstreet

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Re: The Commodore 256
« Reply #11 on: September 25, 2018, 04:55:39 am »
 

Offline rrinker

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Re: The Commodore 256
« Reply #12 on: September 25, 2018, 05:39:17 am »
 What's funny is you probably could say the Commodore systems WERE just consoles that happened to have keyboards and some peripherals. Cartridge ports? Check. Connect to a TV, not needing a special computer monitor? Check. Custom high density chipset to minimize total chip count? Check.

 They just did it better than that really horrid Coleco Adam. Super slow daisy wheel printer that is ALSO the power supply for the whole system? What genius came up with that one? But those Commodore machines had their own issues, like those dog slow floppies (at least until the C128, when operated in native C128 mode - put the thing in C64 mode and they were slow again).
 

Offline Rasz

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Re: The Commodore 256
« Reply #13 on: September 25, 2018, 10:32:26 am »
What's funny is you probably could say the Commodore systems WERE just consoles that happened to have keyboards and some peripherals.

Amiga was supposed to be a console right up to the game crash of 1983. This origin made it both fantastic computer for home gaming, and terrible prospect for upgradeability - everything was hardcoded to specialized chips. Even simple task of playing game from harddrive turned into hot patching ordeal with whdload.
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Offline Bashstreet

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Re: The Commodore 256
« Reply #14 on: September 26, 2018, 12:27:17 am »
What's funny is you probably could say the Commodore systems WERE just consoles that happened to have keyboards and some peripherals.

Amiga was supposed to be a console right up to the game crash of 1983. This origin made it both fantastic computer for home gaming, and terrible prospect for upgradeability - everything was hardcoded to specialized chips. Even simple task of playing game from harddrive turned into hot patching ordeal with whdload.

I do not know what you mean but you can upgrade Amiga pretty much in all aspects from memory to processor from operating systems to modems among many other things.
 

Offline Kleinstein

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Re: The Commodore 256
« Reply #15 on: September 26, 2018, 02:06:23 am »
The amiga was upgradable - though still a low volume product and thus not much 3rd party hardware available at the beginning. Memory upgrades (to 1 MBytes) where very common and much easier than with the early DOS-PCs beyond 640 K - no crazy odd XMS, EMS etc. I am not aware of a cartridge slot found in typical consoles.

Due to few hardware versions in the early time (the Amiga 1000,2000, 500 and CD32) where still pretty much the same - main difference was the case), programming could be done close to the HW (like in consoles). This made some SW to assume the quasi standard HW (ignoring programming rules) and caused possible incompatibilities with later HW upgrades.  This was as bad as the MS-Basic that came with it was assuming 24 bit addressing (and thus violating a OS convention) of the 68000 and thus did not work on a 68020  :palm:   >:(. With the A1200, A3000 and A4000 there where different HW versions and also some external graphics cards. In the early days PCs had similar compatibility problems as well (e.g. assuming fixed 4.7 MHz clock and thus turbo switches).

The way the graphics was handled in the OS was relatively close the graphics hardware with separate bitplanes instead of a straight 1 Bype per pixel mode that later became the obvious choice. This somewhat made a graphics upgrade a little tricky.
In other aspects the OS was very upgradable with the use of unix like libraries. So if wanted things like a standard floppy with HW controller would have been possible.
 

Offline CJay

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Re: The Commodore 256
« Reply #16 on: September 26, 2018, 03:29:36 am »
The amiga was upgradable - though still a low volume product and thus not much 3rd party hardware available at the beginning. Memory upgrades (to 1 MBytes) where very common and much easier than with the early DOS-PCs beyond 640 K - no crazy odd XMS, EMS etc. I am not aware of a cartridge slot found in typical consoles.

I was an Amiga owner, had an A500 complete with A590, then an A1500 with A2920 Flicker Fixer and a stack of 5.25" FH 380MB SCSI drives, memory was maxed out on both to 8MB (can't remember the card name for the A1500 but it used ZIP chips, of which I still have a huge number) and latterly I got my hands on a 68020 accelerator card but never managed to find the MMU chip to finish it off.

The 'no crazy XMS' etc is mostly true but perhaps a little bit misleading because there were several variants of AGNES chip so chip memory would vary per machine depending on AGNES version but I do agree, it was a *lot* simpler than the PC.

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Offline Rasz

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Re: The Commodore 256
« Reply #17 on: September 26, 2018, 06:32:10 am »
Due to few hardware versions in the early time (the Amiga 1000,2000, 500 and CD32) where still pretty much the same - main difference was the case), programming could be done close to the HW (like in consoles). This made some SW to assume the quasi standard HW (ignoring programming rules) and caused possible incompatibilities with later HW upgrades.

The way the graphics was handled in the OS was relatively close the graphics hardware with separate bitplanes instead of a straight 1 Bype per pixel mode that later became the obvious choice. This somewhat made a graphics upgrade a little tricky.

Atari had same problem with STE "upgrade" over ST. Much improved, to the point of hardcoded ST software often not running at all.
Worse is better.  While Amiga RTG(and to lesser extend Atari VDI) was seldom used, Apple shipped Mac with worst video hardware imaginable, but fully featured API in rom. As a result nothing on Mac was hardware accelerated .. until everything was.

With the A1200, A3000 and A4000 there where different HW versions and also some external graphics cards. In the early days PCs had similar compatibility problems as well (e.g. assuming fixed 4.7 MHz clock and thus turbo switches).

External graphic card on Amiga (no idea about Atari) forced you to either swap cables, own two monitors, or forget about all the games. Apple made everyone go thru API and didnt care about hardware. PC maintained backwards compatibility with new versions/evolutions, hardcoded clock assumptions mostly went away past 1987 when everyone realized IBM lost the leader role to Compaq(386 deskpro). Microsoft helped with its religious devotion to backwards compatibility (yay 260 MAX_PATH length limit). Sure XMS/EMS sucked, but old software simply worked.



 This is why there was little chance for worthy C64 successor, aside from maybe incorporating VIC/SID (or even just SID emulation using Paula and crude bank of samples) inside 65C816 powered Amiga. This would provide backwards compatibility, and kickstart(HA!) Amiga adoption. Instead abominations like C128 made everything worse and diluted user trust, "C64 with CPM glued to its ass, something nobody asked for. How about c64 with floppy build in? nah, lets pump c128 at TWICE the cost of 64 with no advantage to 95% of users (gamers). Whats better than 2 CPUs? 3 CPUs in C128D!  more expensive than C64 and floppy bought separately, GENIUS!
Triple CPU actually. Commodore couldnt be bothered to redesign C128D build in floppy. So you had
-always turned off Z80
-8502 doing nothing after issuing disk command
-6502 handling disk, doing nothing otherwise.

3 cpus for the low low price of ... 3 cpus, almost full price of Amiga 500.

People trusted Commodore, and got screwed. 2x better on paper in all the things that didnt matter at the end. Better graphics IF you buy monitor (costing more than C128 itself), faster cpu IF you give up VIC graphic chip with its hardware sprites, more ram so you can wait twice as long for tape drive to load UNLESS you buy a floppy drive (costing more than C128 itself) :-(
C128 with additional floppy drive was the price of Atari 520ST. C128 with floppy and monitor was the price of Amiga 1000."

Commodore 'vision' of C64 successor had three (two useless) 8-bit processors, and two (one useless) graphic chips. Whole company was a train wreck, Tramiel was a questionable businessman, more preoccupied fighting price wars with competition than his own products, or financial health of the company, but at least he controlled that mess. Idiots after him had no clue.
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Online Alex Eisenhut

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Re: The Commodore 256
« Reply #18 on: September 26, 2018, 10:02:28 am »
Ugh, upgrading Amigas... I had an A1000 pretty early in the game, I was still in high school. I had somehow found out about something called LUCAS, a 68020 processor upgrade that plugged into the A1000's CPU socket to replace the 68000.
It was open hardware, you bought the bare PCB and programmed PALs (or GALs?), got the schematic and had to procure the rest of the stuff yourself.
I was in way over my head at the time, both in terms of the money for parts and getting it to work... It never did. :( Never figured out why, and by the time I could have, I was already on the 3000.
So upgrading an Amiga in the early days was not easy. Especially if you didn't know what you were doing. I still wonder why it didn't work... :(
http://www.bigbookofamigahardware.com/bboah/media/manuals/Lucas.pdf
 

Offline Kleinstein

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Re: The Commodore 256
« Reply #19 on: September 27, 2018, 03:14:02 am »
...
External graphic card on Amiga (no idea about Atari) forced you to either swap cables, own two monitors, or forget about all the games. Apple made everyone go thru API and didnt care about hardware. PC maintained backwards compatibility with new versions/evolutions, hardcoded clock assumptions mostly went away past 1987 when everyone realized IBM lost the leader role to Compaq(386 deskpro). Microsoft helped with its religious devotion to backwards compatibility (yay 260 MAX_PATH length limit). Sure XMS/EMS sucked, but old software simply worked.
...
There was a solution for the two monitor problem with an external graphics card. There was an odd scan doubler card available that took the 15,6 kHz horizontal signal and doubles all lines to make is compatible with an normal VGA / multi-sync monitor. So it was possible but quite an odd and extra cost way.

Most of the Amiga software used graphics through the API and thus surprisingly much of the software also runs via an extra graphics card. The more tricky part where quite a lot of programs ignored a possible HW change was with 24 Bit addresses of the 68000 and using the upper 8 bits for something else.  Another possible issues was speed, making some programs (games) run too fast with an 68020 or 68030.

The C128 was a kind of disaster in many aspects and the better 65C815 or similar processor would not have changed that much. At that time the somewhat odd floppy was at it's limits. There where faster and higher capacity (up to 1 MB) floppies available for the PET series, but they where expensive. The cheap PC standard floppy HW is not compatible with the 1541 floppy format. So the extra 6502 for the floppy part was kind of a required part and not that bad if well implemented. Having an intelligent storage device also has some advantages - the 6502 in the floppy was really working hard when the floppy was used.  Having a double speed and capacity (still low data density - more like what single density PC floppies were) floppy with 2 MHz CPU (e.g.65C02A) would have been a real option. With modified ROM the speed of the floppy transfers could be increased quite a lot (AFAIR about 6-10 times), with rather few compatibility issues. Much of the low speed was the slow implementation of the serial bus and AFAIR the C128 mode was already faster.

At that time the 6502 was not that expensive anymore, especially as it was made by Commodor's own chip fab. The Z80 part was kind of odd and likely hardly ever used as CPM was already in decline.

The problem at that time was that is was the time when monitors changed / developed. Having a shared memory graphics was still the standard at that time and also 15.6 kHz horizontal was common and allowed operation with a TV.  It was just a little early for a switch to a separate graphics memory (like VGA).
 

Online Alex Eisenhut

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Re: The Commodore 256
« Reply #20 on: September 27, 2018, 08:13:36 am »
Commodore 'vision' of C64 successor had three (two useless) 8-bit processors, and two (one useless) graphic chips. Whole company was a train wreck, Tramiel was a questionable businessman, more preoccupied fighting price wars with competition than his own products, or financial health of the company, but at least he controlled that mess. Idiots after him had no clue.

Harsh, but correct. The 128 was an error, to put it lightly.
 

Offline sleemanj

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Re: The Commodore 256
« Reply #21 on: September 27, 2018, 09:44:42 am »
Due to few hardware versions in the early time (the Amiga 1000,2000, 500 and CD32) where still pretty much the same - main difference was the case),

You have confused the CD32 with the CDTV - totally different machines, the CDTV is what you are thinking of. 

The CD32 was a games console derived from the A1200 (AGA), the CDTV was a... thing... derived from the A1000 (OCS), not a games console as such, more a, thing that really doesn't have a good description, home edutainment device maybe.  It was, weird.

The CD32 was very squarely directed as a games console on the other hand.
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Offline Rasz

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Re: The Commodore 256
« Reply #22 on: September 27, 2018, 04:34:44 pm »
You have confused the CD32 with the CDTV - totally different machines, the CDTV is what you are thinking of.

The CD32 was a games console derived from the A1200 (AGA), the CDTV was a... thing... derived from the A1000 (OCS), not a games console as such, more a, thing that really doesn't have a good description, home edutainment device maybe.  It was, weird.

The CD32 was very squarely directed as a games console on the other hand.

Both were repackaged last years hardware, late to the market, too expensive, and didnt manage any significant software support.
CD32 was released >year after Sega CD, at same price and with similar CPU performance (68020 ~= 2x 68000), but no hardware 3d (Sega at least tried with actual hardware accelerated polygon engine). Sure, you could convert it back into A1200 after spending 386DX money, real deal!
Who would want to play Wing Commander at 1 (ONE) frame per second?
Code: [Select]
http://www.youtube.com/watch?v=n5wXmeI8w9k&t=500
You can pretty much sum all of those products (C128, CDTV, 600!, CD32) as scams intended to milk sucker customers out of money by selling old overpriced junk. This strategy had to catch up to Commodore sooner than later.
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Offline BrianHG

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Re: The Commodore 256
« Reply #23 on: September 27, 2018, 04:59:46 pm »
People here seem to forget the Amiga 1000 was developed in 1984-85, do you have a clue how f----en expensive ram was then?

The Amiga 2000 was a proper yet simple upgrade path.  (I personally would have liked it to have a 68020 only on the motherboard, even if it was the EC version with the 24 bit limit on addressing)

Thanks to Commodore stupid R&D budget and A500's success in Europe for games, the F---en owners took half the development team and most of the development budget off of the A3000 project to work on the disaster CDTV project.  For the owners of Commodore, game systems meant $, and professional computing meant 0.

Now, thanks to all that shortsightedness, the Amiga 3000 basically just had the flicker fixer already developed for the A2000 instead of what was supposed to be the AGA 256 color, with true byte per pixel capabilities just above the A4000, and yes, with this custom chipset was supposed to be now running at 57Mhz(see note 1) base clock instead of the slower 28mhz of the A4000/A12000 offering a true 1280x960 at 60hz progressive, 256 colors per pixel, 640x480 at true 16 bit color (obviously progressive).  And yes, the A3000 also was supposed to have Motorola's new 16 bit Audio DSP with 16bit stereo sampler/16bitDAC, 64 stereo voices 48Khz audio, no aliasing on pitch bending.  At the release of the A3000, this would have completely roasted most top end PCs by a long shot.

The A4000 was already supposed to be a true 24 bit display, different bit depths in each window with backwards compatibility simple 3D geometry acceleration, the similar GPU used in the second generation NEXT computer which had color.

(Note 1): I discovered, changing the custom chipset 28.63636Mhz reference clock in my A4000 could only run up to around 44Mhz normally.  I also discovered that when changing the 2mb chipram module to 4md, changing the 2m/8m jumper and J503 (I think, it's been a lot of years...), the A4000 would accept 4mb modules in the chipram location, though it only still accessed 2mb, BUT, now, with a -60 ram module, I could run the custom chipset clock oscillator at 56Mhz with fans on the AGA chipsets.  Yes, with custom AGA monitor video mode editing software, I had 1024x768, 1280x960 modes.  Also, with RCS management's Excalibur 040 accelerator, this A4000 using a hacked Light Rave/Light Wave from Newtek for editing and rendering 3D ran circles around anything else at the time.
« Last Edit: September 27, 2018, 05:14:34 pm by BrianHG »
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Offline CJay

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Re: The Commodore 256
« Reply #24 on: September 27, 2018, 06:19:30 pm »
(Note 1): I discovered, changing the custom chipset 28.63636Mhz reference clock in my A4000 could only run up to around 44Mhz normally.  I also discovered that when changing the 2mb chipram module to 4md, changing the 2m/8m jumper and J503 (I think, it's been a lot of years...), the A4000 would accept 4mb modules in the chipram location, though it only still accessed 2mb, BUT, now, with a -60 ram module, I could run the custom chipset clock oscillator at 56Mhz with fans on the AGA chipsets.  Yes, with custom AGA monitor video mode editing software, I had 1024x768, 1280x960 modes.  Also, with RCS management's Excalibur 040 accelerator, this A4000 using a hacked Light Rave/Light Wave from Newtek for editing and rendering 3D ran circles around anything else at the time.


Anything else of comparable price you mean, I was working on clustered Silicon Graphics Indigo systems at a synchrotron facility back then...
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