Papushka@student.umass.edu (12/20/90)
To all you people out there from C= in West Chester: I'm not a very technical person, as many of the Amiga users are. Yet, all of us tend to wonder just how easy/difficult it would be to build a new, rather low-cost custom chip-set that would be: A) Backwards compatable with the current chips B) Adress either 24 bit color or some variation (a higher resolution with more colors.. .at least up to VGA standards I've read many posts from you at C=, which seem to say that the current (original) chipset is so set in its ways (no pun intended) that is nearly impossible to build into the Amiga a higher standard of graphics and sound without creating an entirely new machine. So, my question I guess boils down to this: Is it possible at all for you engineers to produce, within a reasonalbe amount of time, a new custom chipset for the Amiga that is backwards compatable with earlier (current) versions and software and yet sports features (more sound voices/16 bits... more colors) that are superior to today's standard Amiga equipment? Any reply would be appreciated. (If my original post does get through the relay alive..... <sigh>) -Paul Antico / University of Massachusetts at Amherst. "We use Cybers and can't stand 'em"
raible@cbmvax.commodore.com (Bob Raible - LSI Design) (12/21/90)
In article <39640@nigel.ee.udel.edu> Papushka@student.umass.edu writes: >To all you people out there from C= in West Chester: > >I'm not a very technical person, as many of the Amiga users are. >Yet, all of us tend to wonder just how easy/difficult it would be to >build a new, rather low-cost custom chip-set that would be: >A) Backwards compatable with the current chips >B) Adress either 24 bit color or some variation (a higher resolution with >more colors.. .at least up to VGA standards > >I've read many posts from you at C=, which seem to say that the current >(original) chipset is so set in its ways (no pun intended) that is nearly >impossible to build into the Amiga a higher standard of graphics and >sound without creating an entirely new machine. > >So, my question I guess boils down to this: >Is it possible at all for you engineers to produce, within a reasonalbe >amount of time, a new custom chipset for the Amiga that is backwards >compatable with earlier (current) versions and software and yet sports >features (more sound voices/16 bits... more colors) that are superior >to today's standard Amiga equipment? > >Any reply would be appreciated. (If my original post does get through >the relay alive..... <sigh>) > >-Paul Antico / University of Massachusetts at Amherst. >"We use Cybers and can't stand 'em" Instead of replying to your post point by point, I decided to try to answer this in more general terms. We are of course aware that many users desire more colors and higher resolutions. Ham is useful but has its limitations. The features you specifically asked for are reasonable and quite implementable(assuming 24 bit color is referring to palette and not bits per pixel). The costs can probably be controlled to a reasonable level, even though chip cost would be certain to rise somewhat. There are certain factors about the Amiga architecture that stymy rapid introduction of new custom chips. First we have a bitplane architecture unlike our competion, and this prevents us from taking advantage of off the shelf solutions to accelerate the process. Secondly, the upgrade path is difficult due the generality of the Amiga programming model. For example you can't just can't drop in VRAM to accelerate graphics due to alignment issues. According to the model bitplanes could be located anywhere in chip RAM, and even overlap. True, most applications let the llibraries handle memory allocation, but that's not universally true. Compatibility would dictate that we try to maintain as much generality as possible. Coiming up with suitable enhancements is not always easy and take time to develop. Third, the custom chips are designed in older technology, and need to be redesigned in a more suitable process. Nothing we can't handle, just takes time. Finally, we need to design a chip set that is economical enough to be put in low end Amigas for starving students(believe me, I've been there), but has the ability to handle the needs of power-mad ray-tracers and their ilk. So system definition takes time too. If there were any shortcuts, believe me we would have taken them already. I have been following this group rather closely for the last year or so(well actually I skip over a lot, but then you'd probably want me to spend as much time as possible on chip design :3) )! In that time I can't recall anybody from here claiming that we couldn't carry the Amiga forward. I think that you may just be misinterpreting a little healthy pessimism(there's a wall in our path, but it ain't brick - more like gypsum and 2x4's). Don't forget there's all kinds of boards out there that can offer higher colors at higher resolutions. The trick is to seemlessly integrate the display into the Amiga environment. That involves system design, extensive chip design, and a healthy dose of re-coding of graphics lib. Doing it right takes time. I hope I explained why.
Lee_Robert_Willis@cup.portal.com (12/21/90)
DISCLAIMER: When it comes to Hardware, I'm dumb as dirt. On a related topic, I've read here that with a 68030 or 40 CPU, it would be faster to draw the graphics using the CPU, because the custom chips still run at 8Mhz. Why can't the custom chips simply be made to run at a faster clock rate? (i.e. a 68030 can run at 16, 25, 50Mhz, why can't Agnus et. al.?) Lee Lee_Robert_Willis@cup.portal.com
daveh@cbmvax.commodore.com (Dave Haynie) (12/22/90)
In article <37123@cup.portal.com> Lee_Robert_Willis@cup.portal.com writes: >DISCLAIMER: When it comes to Hardware, I'm dumb as dirt. >On a related topic, I've read here that with a 68030 or 40 CPU, it would >be faster to draw the graphics using the CPU, because the custom chips >still run at 8Mhz. Depends. Agnus, et. al. access the bus roughly the same as a 7.16MHz 68030 would with 0 wait states, which is to say, twice the speed of a 7.16MHz 68000. No matter what CPU you have in your system, the CPU can't access chipram faster than the speed of a 7.16MHz 68000. Basically, the chips run a cycle on the chip bus every two clock, but only allow the CPU in on alternate cycles, if at all. On the A3000, this is still the case, but since the CPU his Chip memory with twice the number of bits as does Agnus, CPU and Agnus access are basically equivalent. >Why can't the custom chips simply be made to run at a faster clock rate? >(i.e. a 68030 can run at 16, 25, 50Mhz, why can't Agnus et. al.?) Today's chips are running at their limit. For the same basic reasons Moto had to redesign the 68000 to get to 16MHz or the 68030 to get beyond 33MHz, we would have to redesign the custom chips to go faster. We have an additional constraint -- Moto can charge $200 or more if they like for their faster parts, we have to keep things down to a cost point that'll allow us to actually put them in Amigas. >Lee Lee_Robert_Willis@cup.portal.com -- Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: hazy BIX: hazy "I can't drive 55" -Sammy Hagar
steves@pnet01.cts.com (Stephen Scheck) (12/23/90)
Papushka@student.umass.edu writes: [some superfluous text deleted] >I've read many posts from you at C=, which seem to say that the current >(original) chipset is so set in its ways (no pun intended) that is nearly >impossible to build into the Amiga a higher standard of graphics and >sound without creating an entirely new machine. > >So, my question I guess boils down to this: >Is it possible at all for you engineers to produce, within a reasonalbe >amount of time, a new custom chipset for the Amiga that is backwards >compatable with earlier (current) versions and software and yet sports >features (more sound voices/16 bits... more colors) that are superior >to today's standard Amiga equipment? > >-Paul Antico / University of Massachusetts at Amherst. I'd also like to know if it's feasible to make a new chip set that allows more colors onscreen. Come on, C=, it's been 5 years since Amy came out, and we've yet to see new graphics modes that allow more on-screen colors. I want 8-bit graphics (yes, I know that the HAM kludge allows more on-screen colors overall than 8 bits could, but I want INDEPENDENTLY COLORABLE pixels). Wishing but discouraged, Steve.