Atari vs C64 // was: 8-Bit Computer Poll

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Best 8-Bit

ZX Spectrum
109
41%
Commodore 64
121
46%
Amstrad CPC 464
25
10%
BBC Micro
8
3%
 
Total votes: 263

oswald
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Post by oswald » Fri May 18, 2007 1:27 pm

gury wrote:
oswald wrote: look at the speccy, its faster than c64 or atari. and then look at the speccy games. maybe cpu speed aint everything? software sprites are horribly slow.
Totally wrong!!! Please don't make such assumptions before checking them Oswald.

1 Mhz of 6502 is 3~ Mhz of Z80. So, ZX Spectrum is usually faster than C64, but not faster as Atari 8-bit is. It has 2x as such power. Atari can afford software sprites, because it has custom chips which help limit CPU overhead in such circumstances. There is also ZX emulation in development and it will be optimized.

There is no "better" machine, all are good for what they can do!
its not just comparing mhz's... when it comes to math the z80 is much faster with 16 bit registers, generally there's much more registers, and much more complex instructions, whith the clever usage of all that you can write faster code.

secondly check some speccy demos. I saw speccy doing quite the same stuff in 4x4 what atari demos do. gouraud / phong shading / texturing etc. in a speed like the atari. so whats the plus? well the speccy 4x4 screen is a bitmap fully drawn by the cpu!!! also can you scroll the whole bitmap at 50fps with only using the cpu and copying bytes on atari? well the speccy can, check commando...

emkay
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Post by emkay » Fri May 18, 2007 2:17 pm

oswald wrote: secondly check some speccy demos. I saw speccy doing quite the same stuff in 4x4 what atari demos do. gouraud / phong shading / texturing etc. in a speed like the atari. so whats the plus? well the speccy 4x4 screen is a bitmap fully drawn by the cpu!!! also can you scroll the whole bitmap at 50fps with only using the cpu and copying bytes on atari? well the speccy can, check commando...
If you want, the ATARI can build 100fps. But, you would need a TV set for handling 100Hz also ;-)

The software-scrolling at a resolution of 256 x 192 with 50Hz is no problem either.

oswald
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Post by oswald » Fri May 18, 2007 2:34 pm

so you can move a whole bitmap at 50fps with the cpu ONLY ? according to my calculations a c64 needs ~2.8 frames to copy 32*192 bytes (256x192 in pixels) the code would be lda abs sta abs,x unrolled for each byte. dont think you can do 50fps on the atari. you're like 1.7 ? how many mhz do u have? :) you would need 2.8 mhz...

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focusgaming
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Post by focusgaming » Fri May 18, 2007 2:53 pm

I voted for the Spectrum, but it was a tough choice as the C64 was techinally better I just had more speccy games and more fun! :D
Lee
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http://www.focusgaming.co.uk
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TMR
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Post by TMR » Fri May 18, 2007 2:54 pm

oswald wrote:so you can move a whole bitmap at 50fps with the cpu ONLY ? according to my calculations a c64 needs ~2.8 frames to copy 32*192 bytes (256x192 in pixels) the code would be lda abs sta abs,x unrolled for each byte. dont think you can do 50fps on the atari. you're like 1.7 ? how many mhz do u have? :) you would need 2.8 mhz...
Bit less, he said 256x192 (same as the Spectrum but smaller than the default screen size or the C64). That's 6,144 bytes of data that needs shifting a frame and we're not talking about mapping software sprites in over that either... might be possible if it's just a ROL scroll but it'll be bloody close to the wire! If i get time, i'll give it a try.

markstclair2010
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Post by markstclair2010 » Fri May 18, 2007 3:00 pm

zzzzz

Somebody hand me a joystick (preferably a C=64 stick).

oswald
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Post by oswald » Fri May 18, 2007 3:01 pm

emkay, how can u display a 100hz picture? that would mean the gfx chip need to read at double speed.

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Allas
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Post by Allas » Fri May 18, 2007 5:29 pm

Another thing, someone knows what are the equivalent of a SIO2PC device in C64 machines. I have a ton of software of C64 in diskettes, but I want a connection via PC to download the last stuff.

Please, give me solutions that don't burn my C128.
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TMR
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Post by TMR » Fri May 18, 2007 5:40 pm

TMR wrote:That's 6,144 bytes of data that needs shifting a frame and we're not talking about mapping software sprites in over that either... might be possible if it's just a ROL scroll but it'll be bloody close to the wire! If i get time, i'll give it a try.
Scrap that, i've just tried it and even a single scanline test using unrolled code takes about three scanlines to move; even if i'm generous and say two scanlines that's still 384 scanlines to move that entire screen with 18,432 bytes of code needed as well since it's unrolled! Going to vertical scroll will take twice as many memory transactions (one ROL per byte for horizontal compared to an LDA and STA for vertical) so it's a total non-starter and would need 36K of code even if it wasn't.

And here's an interesting side effect; i just tried the same 32 ROLs on a C64 and it's only taking four scanlines... now, if the Atari is twice the speed of the C64 i'd expect that to be six scanlines but it isn't... in fact, if i put the screen back out to 40 bytes wide on the Atari, it's taking three and a half scanlines when processing during the screen (the C64 code was deliberately passing over a badline as a worst case) so i'm spotting some huge discrepancies here!

oswald
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Post by oswald » Fri May 18, 2007 7:29 pm

Allas wrote:Another thing, someone knows what are the equivalent of a SIO2PC device in C64 machines. I have a ton of software of C64 in diskettes, but I want a connection via PC to download the last stuff.

Please, give me solutions that don't burn my C128.

sorry but there's no plug n play solution, you'll have to soldier a cable, and get a gui for this tool:

http://www.trikaliotis.net/cbm4win

dont forget to dl cbm4win gui aswell.

there was star commander which looked the same and worked the same as norton commander, except it was able to handle c= drives, but under xp its unreliable. try it however if you have a dos only machine (or if you like to boot into dos in case of transfering)

potatohead
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Post by potatohead » Fri May 18, 2007 9:36 pm

Well TMR, software sprites can have hardware assist or not. Hardware assist could be in the form of a blitter chip, for example. This is why I phrased things as I did, not out of poor understanding of how sprites do and don't work.

(kinda pops the bubble huh?)

As for the data movement not being a big deal, it all comes down to time per frame. If the game engine runs faster than necessary for that frame, it's all just fine. Generally speaking, this can often happen when comparing the work required for a given display. Again, put in the context of the two machines, it will be a draw more often than not.

IMHO, the two machines are well balanced in this regard. The faster CPU clock in the Atari against hardware sprites in the C64. There are quite a number of scenarios where these two factors balance out, which is the basis for my comment.

Of course, to you, the C64 is the ultimate censored! That's fine, but it really is showing you know.

I've had really great game experiences on both machines.

I'll even go so far as to say the C64 is an excellent 8 bit gaming machine. I enjoyed the hell out of mine back then. But it's not valid to just claim blanket superiority as you project here, but go right on ahead. Call your mamma in the room and show her the fanboy you really are!

BTW: I didn't keep the C64 however. Still have my VCS & still have my original Atari 400 from that time period. Both of these machines remain distinctive in my mind. I like the game experiences, I like the design, solid construction, variety of input devices, colors, sounds, etc...

I put the A400 out in the game room, people come by and check it out! It looks cool, plays 4 player games, etc... The C64 looks like crap, by comparison. Sorry, but that's just another element to the discussion not being considered here.

It's a holistic thing, not just a few tech specs...

emkay
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Post by emkay » Sat May 19, 2007 3:45 am

TMR wrote:

And here's an interesting side effect; i just tried the same 32 ROLs on a C64 and it's only taking four scanlines... now, if the Atari is twice the speed of the C64 i'd expect that to be six scanlines but it isn't... in fact, if i put the screen back out to 40 bytes wide on the Atari, it's taking three and a half scanlines when processing during the screen (the C64 code was deliberately passing over a badline as a worst case) so i'm spotting some huge discrepancies here!
Hm.... thought you know the A8? Counting Diplay lines means counting Antic's DMA Access. The speed you are searching for, is in the VBI time, which you cannot display.
Have you tried your routines at page 0 ?

emkay
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Post by emkay » Sat May 19, 2007 3:51 am

oswald wrote:emkay, how can u display a 100hz picture? that would mean the gfx chip need to read at double speed.
That was only theory. Ofcourse Antic is "hard wired" to 50/60Hz. But you can adjust the screen down to 576 Bytes to have a viewable resolution and a real fullscreen.
Try to calculate, how much frames per second, the A8 can build there (theoretically).

oswald
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Post by oswald » Sat May 19, 2007 4:50 am

we had a lot of talk about prices, this commercial is more than a proof how cheap the c64 was:


http://www.youtube.com/watch?v=BdfxfrTXyvc

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TMR
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Post by TMR » Sat May 19, 2007 5:01 am

emkay wrote:Hm.... thought you know the A8? Counting Diplay lines means counting Antic's DMA Access.
i thought you knew it Emkay, you were going on about how the Atari is twice as fast as the C64 earlier and that's patently not true is it? i knew the DMA pulls took time away from the program but i honestly hadn't run any speed tests like this previously and merely got on with coding the things i wanted to move - but it seems that nobody else in this discussion has really done that kind of side-by-side check either and, with all the graphics fetches, the Atari is nowhere near double the speed of the C64 so quite a few of claims made in the Atari's favour previously are going to vary from inaccurate to very wrong indeed. Even if there's a vast speed increase during flyback (the only time i know i can't see) it's not going to make up the difference.
emkay wrote:Have you tried your routines at page 0 ?
i must admit that i didn't try running my routine from the zeropage, mainly because it was just a trial of a larger routine that expands out to over 16K in length and i don't think the 256 byte zeropage could hold that...

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