Rybags Posted January 14, 2009 Share Posted January 14, 2009 The Plus/4 isn't the speed demon you might think. It switches to half-clock speed mode in the visible display area, and also due to attribute RAM accesses runs somewhat slower than the A8 in similar modes, despite the same system bus speed. It also "suffers" from the same character-like mapping of bitmap modes, which also slows the '64 down a tad in certain bitmap applications. The Plus/4 does however have an extremely flexible graphics chip despite no sprites and can do all sorts of tricks like h/v overscan, and proper interlaced graphics with software tricks. Link to comment Share on other sites More sharing options...
Crazyace Posted January 14, 2009 Share Posted January 14, 2009 The CPC+ didn't come out till 1990 - a lot later than the a8 The TI99 was the same generation as the a8 and c64 , even though it was a 16 bit processor - the bus was 8 bit ( Only 256 byte of memory were 16 bit - and they held the registers ) Link to comment Share on other sites More sharing options...
Fröhn Posted January 14, 2009 Share Posted January 14, 2009 Actually, if you look at a lot of the C64 games that were hacked to run on the Plus/4 it's pretty obvious that the higher clock speed makes up for the lack of sprites. Usually only games which didn't use sprites were hacked, ofcourse then the higher clockspeed gains something. But there is no way that few extra cycles per frame can compete with the C64 sprite engine. The Plus/4 isn't the speed demon you might think. It switches to half-clock speed mode in the visible display area Just like A8. and also due to attribute RAM accesses runs somewhat slower than the A8 in similar modes, despite the same system bus speed. Character modes on A8 also have to read char matrix data. In a 40 character mode the A8 reads 40 extra bytes every 8th rasterline. The Plus4 has to read 80 bytes, that means: 40 additional cycles taken from the CPU every 8 rasterlines. But there's another factor: DRAM refresh. A8 has 9 per line and 1 in a badline, while +4 has 5 every line. For a character line this results in 24 more refresh cycles on A8 than on Plus4, and then there is 112 border rasterlines too which count for another ~20 cycles gain per character lines (depending on how many charlines you have). So atleast for 40 character modes, +4 and A8 are about the same speed. Link to comment Share on other sites More sharing options...
Thorsten Günther Posted January 14, 2009 Share Posted January 14, 2009 Man, Star Raiders II (aka Last Star Fighter,) is SOooooOOOooo good. That game is awesome. I love all the different elements, the space combat, the big base ships, soaking energy from the sun, the barrier, the planet side combat and bombings. Great stuff that the c64 version doesn't hold a candle to The barrier misses in "Star Raiders II", it only appears in TLS. This caused a major change in the gameplay. To be honest, I consider TLS to be a much better game. Thorsten Link to comment Share on other sites More sharing options...
atariksi Posted January 14, 2009 Share Posted January 14, 2009 ...Still stand by the notion of it coming down to the programmers and utilizing the abilities of the system. It is also who has better software available for their system and that is what attracts people to buy them. Its very rarely the hardware abilities itself that sells the system. Yeah, people may buy a system for it's software but a computer is superior or inferior by its hardware. Atari has more hardware resources than other 8-bit machines over-all for all tasks that can be done by a machine. Link to comment Share on other sites More sharing options...
atariksi Posted January 14, 2009 Share Posted January 14, 2009 ...100% agree. except that some 8bits out perform the Atari 8 bits. ok , C64 and A8 are comparable the A8 outperfom the C64 on certain side but the C64 outperform the A8 on other. And that's clear that the A8bit has not been fully exploited. The Commodore plus 4 also outperfom the A800 and the C64 on some point. (very few...) But the Amstrad CPC 6128+ (the "plus" is important) cleary outperform on ALL point Atari 800 and C64 . (except may be music) http://www.system-cfg.com/detailcollection.php?ident=3 ... At the time when 8-bit machines were peaking, 6128+ wasn't around nor was Apple IIgs. Those later developments can't be compared. It's like someone struck out with the bases loaded in the bottom of the ninth to end the game with his team trailing by 1 run and later goes in his backyard and hits a few grandslams with friends. Let's keep things consistent. Atari was the superior hardware at the time of late 70s, early 80s before companies focused on 16/32 bit machines. Link to comment Share on other sites More sharing options...
Crazyace Posted January 14, 2009 Share Posted January 14, 2009 I was reading this again : http://www.amigahistory.co.uk/jayinterview1.jpg ( from http://www.amigahistory.co.uk/jayminerinterview.html ) It really shows how Atari screwed up way way before the Tramiel's took over... Imagine what would have happened if the A8 team had stayed on at Atari Link to comment Share on other sites More sharing options...
emkay Posted January 14, 2009 Share Posted January 14, 2009 why can Speccy do this: http://de.youtube.com/watch?v=vzm9KkJ5lGI&...feature=related and Commie & Atari not? 7 MHz... the Atari can do this with 1.79MHz at the resolution of 160x100... ;P Link to comment Share on other sites More sharing options...
frogstar_robot Posted January 15, 2009 Share Posted January 15, 2009 I was reading this again : http://www.amigahistory.co.uk/jayinterview1.jpg ( from http://www.amigahistory.co.uk/jayminerinterview.html ) It really shows how Atari screwed up way way before the Tramiel's took over... Imagine what would have happened if the A8 team had stayed on at Atari The only thing worse than Commodore marketing was Atari marketing. And by that I mean Warner was worse and Tramiel was the worst. I believe at the time Commodore was a better place for that tech. Warner Atari wasn't even sure if they wanted to be in computers and video games much less build next generation ones. Tramiel just wanted the chipset but didn't want Miner and his team. If Warner HAD developed it we've gotten an interesting line of computers and/or consoles out of it that only a few old die-hard geeks would still be talking about. Kinda like now but there would far fewer of them and I doubt Amiga would be the modern day zombie of the I.T. landscape staggering about and chanting "braaaaaaaiiins". This is because neither Warner Atari nor Tramiel Atari would have allowed to evolve as it did under Commodore. We wouldn't have seen things like the Video Toaster. I have no idea what the OS would have been like but the one Commodore adapted to it WAS innovative even if it wasn't all that Miner wanted for it. On the bright side, we wouldn't have Commodore fanbois who only acknowlege Miner's genius when the work has a Commodore nameplate on it. Link to comment Share on other sites More sharing options...
Rybags Posted January 15, 2009 Share Posted January 15, 2009 Commodore made it's share of mistakes with the Amiga too. Too highly priced on initial release, very buggy OS until 1.3 and even then still leaved much to be desired. Never gave it the proper 16 bit sound it so sorely deserved. Failed to captitalise properly on advances in technology in general and the 68K series in particular. Case in point - the 600 was a bit of a disaster, they should have at least given it a 14 MHz 68000 and could still have kept it price competitive and away from the higher end market occupied by the 1200, 3000 etc. Link to comment Share on other sites More sharing options...
frogstar_robot Posted January 15, 2009 Share Posted January 15, 2009 (edited) Commodore made it's share of mistakes with the Amiga too. Too highly priced on initial release, very buggy OS until 1.3 and even then still leaved much to be desired. Never gave it the proper 16 bit sound it so sorely deserved. Failed to captitalise properly on advances in technology in general and the 68K series in particular. Case in point - the 600 was a bit of a disaster, they should have at least given it a 14 MHz 68000 and could still have kept it price competitive and away from the higher end market occupied by the 1200, 3000 etc. I agree that Commodore made mistakes but were still better stewards of Miner's 16-bit work than either Warner or Tramiel Atari would have been. Warner Atari was dithering and in that time-frame hemorrhaging money and Tramiel Atari was just cheap whatever good Jack did others want to cite. That and Tramiel just wanted the chipset from Miner's team but not the team. So a "Tramiel Amiga" would have only evolved in trivial ways just like the ST did. The pinnacles of the ST line were the Falcon and the TT. Neither provide much competition to a tricked out Amiga 4000. Commodore also put off the mistake of subjecting engineers and software devs to "TPS Report Syndrome" longer. If a company is to be innovative then being crass to the talent is just stupid. The Tramiels were infamous for doing things like knocking 7800s off the table. I agree that pricing on the lower end Amigas was higher at first. The major reasons I went with a 520ST were one that I could (barely) afford it and two I didn't understand at the time that the Amiga was much more like my beloved 800XL than the ST turned out to be. It wasn't a terrible machine but the STs I've seen didn't impress me nearly as much as the Amigas friends I made in college had. I do think you are being a bit rosy about the "introductory Amiga that could have been". This stuff was so frightfully expensive then. A 512MB upgrade for my 520ST was in the $400 dollar range and absolutely prohibitive for my teenage budget. I imagine the 14Mhz 68000 part commanded quite the premium too. For all that, the Amiga still destroyed the Macs in terms of value per dollar (as did the ST). Anybody have some of the old Computer Shoppers? Sure the Amiga OS liked to meditate on that Yoga mat but when it was working....wow! That trick with sliding desktops and fullscreen apps over top of each other was just amazing. That and it was really first out the consumer gate with multi-tasking. Pity that it wasn't first out the gate with "memory protection". The one thing they didn't add at first was a true memory controller and with that the Amiga could have been more on a par with the UNIXes rather than infamous for crashing. But still...... Edited January 15, 2009 by frogstar_robot Link to comment Share on other sites More sharing options...
Rybags Posted January 15, 2009 Share Posted January 15, 2009 Yeah, thinking about it, maybe it was for the best. One of Atari's big downfalls was designing great hardware but then either/both going closed architecture/not enhancing it along the way. The STe was about Atari's only decent product enhancement if you ignore things like models with larger RAM, or the backward compatability of the 7800. But even then, it was still lacking, and was what the ST should have been in the first place. Link to comment Share on other sites More sharing options...
FastRobPlus Posted January 15, 2009 Share Posted January 15, 2009 They say Commodore made mistakes with the Amiga. Maybe... Commodore and Atari were home computer manufacturers that failed to adapt to the end of the home computer era. A lot of the marketing mistakes were sort of moot in light of this fact. Really, Amiga might have done better if it had have been a chipset used in clones rather than an all-new PC. If it had been adopted and caught on, it might have created an audio/video/DMA standard that would have pushed the clones ahead faster than they did with the path they took through the CGA/EGA/MCGA/VGA, and AdLib/Soundblaster standards. or maybe not. Link to comment Share on other sites More sharing options...
peteym5 Posted January 15, 2009 Share Posted January 15, 2009 100% agree. except that some 8bits out perform the Atari 8 bits. ok , C64 and A8 are comparable the A8 outperfom the C64 on certain side but the C64 outperform the A8 on other. And that's clear that the A8bit has not been fully exploited. Thankyou. Looking at the Amstrad Games reminds me something close to a SEGA Genesis level of graphics but seem to play alittle slower. Would expect that to happen reading up on the system specs. Amdrad was not sold here in the United States and probably why I never heard of one. You can say the C64 performs better in some ways. You can make the same argument for a the 8-bit Nintendo. Which is just about the only 6502 based system that out performs the Atari 8-bit. However many do not like some of the NES ports from A8 games like Boulder Dash, Super Pitfall against Pitfall II. The 7800 had better sprite abilities. What killed the 7800 was they did not have games like Super Mario and Zelda that sold the system. Atari was trying to compete with MS. Pacman and Pole Position and did not make any great games to sale it. You really need some killer applications to show off the abilities of your console or computer right away to sale it and that is what Nintendo and Sega had done to boost their systems. Link to comment Share on other sites More sharing options...
Rybags Posted January 15, 2009 Share Posted January 15, 2009 Quick Loop Benchmark A8 vs Plus/4 Assembler program that has a nested loop, A starting at $80, embedded DEX and DEY loops. Default screen mode on both machines (in emulators). Atari: PAL 35.8, NTSC 38.41 seconds Plus/4: PAL 37, NTSC 41 seconds Of course, there are other variances like the VBlank/System timer IRQ routines that may slow down things, although the Atari VBI does lots of shadow register stuff, but the Plus/4 has to scan the keyboard. But going on those figures, the Atari has a slight edge. Link to comment Share on other sites More sharing options...
Fröhn Posted January 15, 2009 Share Posted January 15, 2009 They say Commodore made mistakes with the Amiga. Maybe... Commodore and Atari were home computer manufacturers that failed to adapt to the end of the home computer era. There was no end of the home computer era. The PC has taken over the home computer market and most PCs these days are used as home computers. What Atari and Commodore failed to do at some point of time: Keep up with the hardware development. For years the Amiga chipset wasn't improved, and when it was, the new chipset didn't compare too good to standard PC hardware of that time. Same for Atari but in 8 bit age, and when Tramiel entered the company there wasn't too much money left so he had to try getting everything as cheap as possible which might explain that he didn't want to pay much for the Amiga chipset and didn't buy the whole company. Of course, there are other variances like the VBlank/System timer IRQ routines that may slow down things, although the Atari VBI does lots of shadow register stuff, but the Plus/4 has to scan the keyboard. But going on those figures, the Atari has a slight edge. Just disable IRQs. On +4 it's easy: SEI. Link to comment Share on other sites More sharing options...
frogstar_robot Posted January 15, 2009 Share Posted January 15, 2009 (edited) They say Commodore made mistakes with the Amiga. Maybe... Commodore and Atari were home computer manufacturers that failed to adapt to the end of the home computer era. From the marketing at the time, the ST and Amiga didn't play up "home computing" so much even though 99% of both machines wound up being glorified game consoles. Both seemed to be trying to be the "affordable Macintosh" though neither company officially sanctioned the inevitable emulation products. The mainstream PC OS was still DOS and mainstream PCs were still running stodgy menu driven business software and really grotty looking games with that beeper for sound when both machines were introduced. These things came with mice and desktop GUIs. People who might want a Mac but couldn't afford one and perhaps found them boring when not using a WYSIWYG word processor were a conceivable market. Perhaps the real mistake was catering to geeks a bit too much and not so much to the artier types that went for Macs. Come '88 we start seeing PCs with the Adlib board and VGA. Those machines were top end and rather expensive and PCs of that magnitude didn't start getting affordable until 90 and that is when they became mainstream for gaming. I saw Doom and Descent on Radio Shack branded PCs in '92. Games like Myst and 7th Guest weren't far behind. The writing really was on the wall at that point. The time to adapt the Amiga into a PC chipset would have been when the Adlib and VGA were getting common but the mentality just didn't exist. It also wouldn't have made much sense with anything less than a 286 and a 386 would have been better. The window to do that was short and the mentality simply didn't exist to exploit it. Even that would have only bought so much time before it had to compete with the likes of Creative and NVidia. And as just another multimedia chipset it wouldn't have seemed so special running Windows. Edited January 15, 2009 by frogstar_robot Link to comment Share on other sites More sharing options...
JamesD Posted January 15, 2009 Share Posted January 15, 2009 I was reading this again : http://www.amigahistory.co.uk/jayinterview1.jpg ( from http://www.amigahistory.co.uk/jayminerinterview.html ) It really shows how Atari screwed up way way before the Tramiel's took over... Imagine what would have happened if the A8 team had stayed on at Atari I keep trying to tell people that Atari was screwed up before Tramiel but people like to blame him because of his association with Commodore. Sadly, the screwup started under the original owner but people don't seem to want to believe. Link to comment Share on other sites More sharing options...
Rybags Posted January 15, 2009 Share Posted January 15, 2009 (edited) Just disable IRQs. On +4 it's easy: SEI. I know... but then I suspect we lose the TI$ count. I've got docs here, but pretty sure that the half-speed thing happens on the entire scanline of the 200-line main display area, and not just the text area. Taking that into account and Atari's 9 vs 5 refresh cycles seems to justify the results I got. Edited January 15, 2009 by Rybags Link to comment Share on other sites More sharing options...
Fröhn Posted January 15, 2009 Share Posted January 15, 2009 Just disable IRQs. On +4 it's easy: SEI. I know... but then I suspect we lose the TI$ count. TI$ is quite inaccurate anyway. It would be better to measure the free cycles per frame. I've got docs here, but pretty sure that the half-speed thing happens on the entire scanline of the 200-line main display area, and not just the text area. Normally yes (it's 25 text lines = 200 rasterlines) but +4 allows to skip display lines. Link to comment Share on other sites More sharing options...
Rybags Posted January 15, 2009 Share Posted January 15, 2009 Well, it's easy enough to calculate cycles lost/stolen. Rerun on Atari - to be more fair, with a 25 line high text display. PAL 36.36, NTSC 39.166 Link to comment Share on other sites More sharing options...
Fröhn Posted January 15, 2009 Share Posted January 15, 2009 Well, it's easy enough to calculate cycles lost/stolen. Rerun on Atari - to be more fair, with a 25 line high text display. PAL 36.36, NTSC 39.166 PAL A8: 23928 free clock cycles per frame PAL P4: 22882 free clock cycles per frame Link to comment Share on other sites More sharing options...
Rybags Posted January 15, 2009 Share Posted January 15, 2009 24280 actually. Only 1 Refresh cycle steal on first line of 40 byte text modes. Link to comment Share on other sites More sharing options...
peteym5 Posted January 15, 2009 Share Posted January 15, 2009 I was reading this again : http://www.amigahistory.co.uk/jayinterview1.jpg ( from http://www.amigahistory.co.uk/jayminerinterview.html ) It really shows how Atari screwed up way way before the Tramiel's took over... Imagine what would have happened if the A8 team had stayed on at Atari I keep trying to tell people that Atari was screwed up before Tramiel but people like to blame him because of his association with Commodore. Sadly, the screwup started under the original owner but people don't seem to want to believe. A good example of this is the way the 5200 was put together. Not made compatible with anything, Analog Joysticks that were hard to center, different cartridge port, and the hardware was mapped in different locations. Plus it cost way more than the 2600 or any game console of that time. If they simply used the same memory map, cartridge port, and joysticks, it would have been cheaper and would have a huge game library ready right away. Its cartridge port could address 32k directly. only big advantage. I cannot say Tramiel made all bad decisions, The XEGS should have happened much sooner to compete with Nintendo. But in 1984/1985, everyone thought the Game Console was dead so Atari was gearing toward computers. It wasn't the Game Console was dead, the 2600 was dead after releasing a poor port of Pac-Man, ET, and a flood of poor games coming from all those different companies. People were looking for better game technology and the C64, A8, and eventually the NES all had them. All it took for one to become popular was a "Killer Application" and that ended up being Super Mario Bros. Link to comment Share on other sites More sharing options...
Fröhn Posted January 15, 2009 Share Posted January 15, 2009 (edited) 24280 actually. Only 1 Refresh cycle steal on first line of 40 byte text modes. Seems it isn't as easy as you think to calculate the free cycles, because 23928 is right and 24280 is wrong: 114*312 -9*312 (DRAM refresh cycles) +8*25 (DRAM refresh cycles on badlines only waste 1 not 9) -40*200 (bitmap fetches) -40*25 (char matrix fetches) -(25+2+2+3) (display list fetches) = 23928 Here's the code to prove it: a8measure.zip Loop cycles: 6+(64*5+1)*73+73*5+1+23*5+1+2+2+3 = 23928 Edited January 15, 2009 by Fröhn Link to comment Share on other sites More sharing options...
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