Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site cadovax.UUCP Path: utzoo!watmath!clyde!bonnie!akgua!sdcsvax!sdcrdcf!trwrb!trwrba!cadovax!keithd From: keithd@cadovax.UUCP (Keith Doyle) Newsgroups: net.micro.atari Subject: Re: Atari 800XL superior to c64? Message-ID: <340@cadovax.UUCP> Date: Thu, 20-Dec-84 15:01:57 EST Article-I.D.: cadovax.340 Posted: Thu Dec 20 15:01:57 1984 Date-Received: Sun, 23-Dec-84 01:22:03 EST References: <212@eneevax.UUCP> Organization: Contel Cado, Torrance, CA Lines: 77 >I have noticed several comments in this newsgroup stating that >the graphics on the atari is superior to the c64. I personally >have a c64 although today the atari is a better buy. However, I >always thought that the c64 had better graphics and sound >hardware than the atari. I realize that for basic programming >the atari graphics and sound is very easy to use since the >keywords are built into basic. But for applications programs >and games the c64 seems to have the edge. It has 16 colors in >the hi res mode (limited to two different colors in any 8x8 block) >vs only 2 shades for the atari. The sprites in the c64 can be >moved in the x and y directions where as the player missiles >in the atari can only be moved horizontally. The sound chip on >the c64 is a real synthesizer with ADSR features, filtering, the >ability to modulate one voice with another, and external input >as compared with atari's more primitive distortion parameters. >I have heard that the 800XL's have a newer antic chip that >allows more graphics modes, but on the surface at least the >c64 seems to have the edge. I am sure that there are some arguments >for the atari that I may have missed and I would enjoy hearing >more pro's and con's about the two machines. Some of these features are hard to compare. Your description of the Commodore '16 colors in hi res' obviously has limitations, (only 2 in any 8x8 etc.) The Atari features are different and may also have limitations. True, the Atari technically only has 2 colors in hi-res, but with proper use of the display list, you can have 128 colors (or is it 256?), limited to two different shades on any raster line. With the display list, you can mix graphics and text modes on the screen like crazy, ie: a screen with 1. four raster lines of hi-res, then 2. a text line, then 3. 20 pixel lines at medium res, etc. ad infinitum (or at least until the bottom of the screen) The display list will also facilitate scrolling of all or part of the screen either horizontally or vertically without moving any of the actual data. Display list interrupts can be used to divide the 4 (actually 5) players into seperate entities, provided they only move horizontally. (actually you might even be able to do vertical movement like this with some cute tricks). In this way, each of the 5 players could be divided into up to 192 individual horizontal moving 'sprites'. Of course at 192, each sprite is 8 horizontal by 1 vertical. Collision detection is built in for player-player, player-background, etc. but I suppose the Commodore may have this feature. I've heard nothing about any display-list type features in the C64. If there are any, I'd like to hear about them. I must admit though, the Atari sound generators are not particularly impressive. The best feature is that there are 4 of them and you can combine them for more sophisticated effects. The worst feature is that there is only 1 'tone' while there are 7 'noises'. The 1 'tone' is approximately a sine wave, so you don't have much control over timber. You can change the clock rate to the generators in order to drop to lower octaves (more bass!) and you can inter-combine them in some odd ways that I haven't gotten around to experimenting with. I don't particularly miss an ADSR, as this is a slow enough function that it can be 'simulated' with a clock interrupt routine. (nice not to have to do it that way though) One feature however, is the volume-only mode, where you turn off the sound generators, and use the volume control as a 4 bit D/A. S.A.M. uses this for it's speech synthesis output, and does an excellent job, however, you have to turn off all interrupts and DMA etc. because they affect the timing adversely. This means a blank screen when you use this sound feature. I don't know much about the C64 except it has 32 sprites. I guess it just uses the T.I. 9918? (no display list or associated interrupts). All I know about the sound generators is what was said in the above referenced article. I would like to know what versions of FORTH people are using on the C64. I use it exclusively for Atari programs, and would like to know what the best commercially available C64 version is. Keith Doyle {ucbvax,ihnp4,decvax}!trwrb!cadovax!keithd "You'll PAY to know what you REALLY think!"