classic battle atari 8bit vs commodore 64

[supercat]

Digital recording requires (to do it efficiently and reliably) a different type of head and a different magnetic coating. Furthermore, IIRC digital recording on tapes wasn't used until the mid 80's.

 

Huh? Digital recording was used on tapes in the 1960's if not before.

 

While driving a conventional analog head with digital-drive methods on conventional audio tape will not yield results as good as what could be achieved using heads designed for the purpose, it would still be an easy improvement over using analog methods. When storing digital data on tape, square waves are supposed to be square. Why use circuitry to try to smooth off waveforms when the goal is to have nice sharp ones?

[Bryan]

Digital recording requires (to do it efficiently and reliably) a different type of head and a different magnetic coating. Furthermore, IIRC digital recording on tapes wasn't used until the mid 80's.

 

Huh? Digital recording was used on tapes in the 1960's if not before.

 

While driving a conventional analog head with digital-drive methods on conventional audio tape will not yield results as good as what could be achieved using heads designed for the purpose, it would still be an easy improvement over using analog methods. When storing digital data on tape, square waves are supposed to be square. Why use circuitry to try to smooth off waveforms when the goal is to have nice sharp ones?

 

I think the main difference is certified media. If you buy a data tape, it has been checked for consistency from end to end. Audio tape could be used only if a transition or two could be messed up every so often, which FSK can usually handle because of its slower response.

 

The circuit would translate from analog to digital. But the digital outputs doesn't necessarily means "data bit". You can use digital encoding techniques combined with FSK. We talked about this some time ago if you remember, and I understand that's precisley what some C64 turbo software do.

 

Hehe, I posted a reply without much time to catch up on the thread. I guess my post was a little redundant.

Edited July 29, 2007 by Bryan

[JamesD]

Cassette tape systems were based on tone-decoding, much like how tone dialing works. The signal on the tape would alternate between two frequencies and a simple circuit would recognize which one and alternate a data bit. It would take a certain number of cycles for the detector to change states, so your two frequencies had to be higher if you wanted faster rates. Higher frequencies mean better QC and more maintenance is required, and the higher bit rate means tape dropouts are more of a problem. Everyone picked a value that they thought would lead to the fewest service call, I bet.

Ok... I looked up the patent. It's actually related to what type of tape deck you use. If a cassette deck isn't computer compatible it doesn't invert the signal from the tape to it's proper phase. On the CoCo the load routines used the transitions instead of looking for a specific order of high and low parts of the sign wave and it was able to use about any decent cassette deck instead of just computer compatible ones. I think a side benefit was that if the sign wave on the tape was distorted slightly the machine didn't care as much as other systems.

 

http://www.freepatentsonline.com/4468752.h...amp;stemming=on

[ijor]

Huh? Digital recording was used on tapes in the 1960's if not before.

 

You are right, I mixed up things. They were used probably around the 50's, with the very first IBM tape units.

 

While driving a conventional analog head with digital-drive methods on conventional audio tape will not yield results as good as what could be achieved using heads designed for the purpose, it would still be an easy improvement over using analog methods. When storing digital data on tape, square waves are supposed to be square. Why use circuitry to try to smooth off waveforms when the goal is to have nice sharp ones?

 

I doubt very much you could use digital recording on a standard tape-deck and tape (at least at costs nearly as low as using analog recording).

 

Your problem is not the non-square waveform. You never get a sharp squarewave, not even with digital recording. Hook a scope to a floppy head and you will see what I mean.

 

I think the main difference is certified media. If you buy a data tape, it has been checked for consistency from end to end. Audio tape could be used only if a transition or two could be messed up every so often, which FSK can usually handle because of its slower response.

 

I think you are talking about a different thing.

 

One thing is higher quality media for recording digital data using analog linear recording (FSK is always analog recording). Another thing is digital magnetic recording, which saturates the surface and doesn't use FSK at all.

[supercat]

Your problem is not the non-square waveform. You never get a sharp squarewave, not even with digital recording. Hook a scope to a floppy head and you will see what I mean.

 

I did an ADC-based magstripe reader. That good enough?

 

The raw signals from the playback head are indeed not square, but they have extremely sharp transitions. The playback signal is the derivative of the recorded signal: ideally, the playback signal would be zero except for a brief but huge pulse at each flux reversal (since the derivative of a square wave is an impulse wave). In practice, the pulses aren't quite that sharp, but they're still much more crisp and precise than the audio output would be.

 

One thing is higher quality media for recording digital data using analog linear recording (FSK is always analog recording). Another thing is digital magnetic recording, which saturates the surface and doesn't use FSK at all.

 

I see no reason not to saturate the oxide on the cassette when recording data. In audio recording, saturating the oxide will cause distortion, which is bad; in digital recording, there are only two meaningful signal levels anyway, so why not saturate.

 

Once I find my DIN to RCA cable, I'll hook up my C128 and see what sort of performance I can get from its cassette deck.

[ijor]

In practice, the pulses aren't quite that sharp, but they're still much more crisp and precise than the audio output would be.

 

Of course. And that's for a variety of reasons, not only because of a difference in the original signal. But also because all the components in both the recording and reading channel. Replacing the whole system for components optimized for digital recording wouldn't be (at the time) so cheap at all.

 

I see no reason not to saturate the oxide on the cassette when recording data. In audio recording, saturating the oxide will cause distortion, which is bad; in digital recording, there are only two meaningful signal levels anyway, so why not saturate.

 

I didn't say you can't saturate. I said you won't get the same result as when using media designed specifically for this purpose. An audio tape is manufactured for wide dynamic range, for a mixed bias, etc. Exactly the opposite that you want when using digital recording.

[carmel_andrews]

Re; The C64 Vs A8, whilst both machines are ‘better spec’d’ against the competing machine in certain areas, if you add all the differences up, they cancel each other out, so the machines are pretty much the same

 

Someone mentioned the MSX…that was a good machine, technology wise, it was as good a machine the Z80 computer market got to competing technology wise with the A8 and the C64, unfortunately it suffered software wise (i.e. most of the games looked as though they’d been ported from the Amstrad or Speccy) the games might have looked mega. On a speccy/Amstrad but was nothing special or so-so on an MSX

 

Whilst the MSX did have a fairly sizeable portfolio of ‘MSX exclusive’ software, unfortunately very little of it originated or was produced by non Asian/Japanese companies, in Europe/UK even the Amstrad CPC series was better supported then the MSX, essentially the MSX suffered the same problems the PC Engine suffered from, namely lack of support for non Asian or Japanese games companies

 

Also, I forgot to mention that the companies behind the MSX also tried to ‘amiga-ise’ the MSX range, unfortunately the machine itself wasn’t seen much (or rarely) outside Asia or Japan, I can’t remember the spec’s exactly but it had more colours, more sprites, higher resolution then the Amiga and like the ST featured a Midi port and had improved sound capabilities and apparently it had something similar to the A8’s Display list but this time you could reprogram the graphics resolution of the machine’s graphics hardware (going from a review I remember seeing in a general computer magazine in the 87/9 period, even the reviewer stated that the likelihood of this machine coming to Europe/UK in any quantity was remote at best)

[Bryan]

Hey, don't hijack our tape recording/6800 CPU thread with your A8 v C64 trolling.

 

oh wait...

[thomasholzer]

ZZAP!64 mentions, the A8 crunches code twice as fast as the C-64

[JamesD]

Someone mentioned the MSX…that was a good machine, technology wise, it was as good a machine the Z80 computer market got to competing technology wise with the A8 and the C64, unfortunately it suffered software wise (i.e. most of the games looked as though they’d been ported from the Amstrad or Speccy) the games might have looked mega. On a speccy/Amstrad but was nothing special or so-so on an MSX

The MSX was very popular in some countries and has one of the more active communities in the 8 bit world.

http://www.msx.org/msxforum.html

 

Hey, don't hijack our tape recording/6800 CPU thread with your A8 v C64 trolling.

He clearly digressed into MSX land making the post perfect for this thread.

However... in the interest of dragging the off topic portion of his post more on topic with our off topic thread...

But did the MSX have a decent tape interface? Hmmmmm?????

And did any of them use a 64180 instead of a Z80? It is 20% or more faster than the Z80 once in native mode.

There... that should do it!

 

ZZAP!64 mentions, the A8 crunches code twice as fast as the C-64

And Franky say relax!

(sorry... couldn't resist the 80s reference)

 

Actually, if you are just number crunching that's true.

But then the BBC Micro and some Ohio Scientific machines were faster than the Atari.

(I say some because it was an option you had to buy on OSI)

So? Does that make them better than the Atari?

 

Once you start coding games and clock cycles get stolen here or there to do this or that... the water gets muddy.

If you were to write an arcade game in BASIC, the C64 has a clear advantage do to the more modern sprite hardware.

The Atari requires you to move sprite data within the player missile buffer for up and down movement.

The C64 BASIC is slightly faster unless you upgrade the Atari.

 

That brings up something I thought Atari really missed the mark on. The upgradeable language on a cart was one of the best ideas they had... and they dropped it rather than creating their own Extended Basic which would have demonstrated the design feature as an advantage.

They could have just marketed someone else's upgrade. The floating point speed should have been dealt with early on as well.

That killed them in a lot of magazine benchmarks.

But then the C64 had plug in BASIC expansions and you could always switch to RAM mode to load a language so I guess that isn't such a big deal.

 

FWIW, the TANDY CoCo also didn't appear to be blindingly fast in BASIC benchmarks either but most machines after the first board revision or two supported a high speed poke where the CPU went roughly twice as fast. The COCO 3 had a ROM version that speeds up BASIC execution by 30% just by changing the way the keyboard was read... which would have made it one of the fastest machines out there once in double speed mode. But I never saw magazines mention any of that outside the Coco realm. The Coco 3 also has an 80 column text mode. The C128 and Apple II series are the only other popular 8 bit gamer systems that had that feature built in that I'm aware of.

 

CPU speed does matter but there are a lot of other factors that determine whether one machine is "better" than another. It's very subjective and depends on what criteria you compare machines by.

Edited July 30, 2007 by JamesD

[Fröhn]

ZZAP!64 mentions, the A8 crunches code twice as fast as the C-64

And Franky say relax!

(sorry... couldn't resist the 80s reference)

 

Actually, if you are just number crunching that's true.

 

 

But then the BBC Micro and some Ohio Scientific machines were faster than the Atari.

Also the ZX Spectrum is faster than the Atari.

 

If you were to write an arcade game in BASIC, the C64 has a clear advantage do to the more modern sprite hardware.

The Atari requires you to move sprite data within the player missile buffer for up and down movement.

The C64 BASIC is slightly faster unless you upgrade the Atari.

On C64 almost all games were coded in assembler. C64 BASIC was only useable for disk IO and text output, but nothing else. Concerning games, C64 BASIC was only used for a few text adventures and text based strategy games. When you started coding on C64, you learned pretty fast that there was no way to avoid assembly language

 

But then the C64 had plug in BASIC expansions and you could always switch to RAM mode to load a language so I guess that isn't such a big deal.

Yes, but those BASIC cartridges had a big flaw: You could only run the programs if you owned the cart. So nobody used them to write their programs too.

 

CPU speed does matter but there are a lot of other factors that determine whether one machine is "better" than another. It's very subjective and depends on what criteria you compare machines by.

Especially for A8 and C64 it's the graphic and sound hardware which defines those machines. Back then the CPU defined almost nothing. The Commodore PET had 1 MHz 6502 in 1976. C64 came out with 1 MHz 6502 in 1982, still it's clear that the C64 is the way better computer.

[Bryan]

That brings up something I thought Atari really missed the mark on. The upgradeable language on a cart was one of the best ideas they had... and they dropped it rather than creating their own Extended Basic which would have demonstrated the design feature as an advantage.

They could have just marketed someone else's upgrade. The floating point speed should have been dealt with early on as well.

That killed them in a lot of magazine benchmarks.

But then the C64 had plug in BASIC expansions and you could always switch to RAM mode to load a language so I guess that isn't such a big deal.

Atari did offer a version of Microsoft Basic, as well as several other languages. They just cost more money.

 

The Commodore PET had 1 MHz 6502 in 1976. C64 came out with 1 MHz 6502 in 1982, still it's clear that the C64 is the way better computer.

Uh oh... bashing the 800, 64, Apple, Spectrum and all is okay, but you DO NOT want to piss off the PET fanboys!!!!

[JamesD]

Atari did offer a version of Microsoft Basic, as well as several other languages. They just cost more money.

Yeah, but they weren't an upgraded version of Atari BASIC so they wouldn't run the old code as well as new.

It should have just shipped with newer machines and people with older versions could buy the upgrade.

 

There's no reason BASIC XL or something similar couldn't have be sold by Atari.

Does anyone actually have Microsoft Basic for the Atari? I've never seen the cart myself.

 

The Coco had Color Basic or Extended Color Basic but the overwhelming majority of machines had Extended Basic installed even though it cost more.

It was so popular it was standard on later machines.

 

The Commodore PET had 1 MHz 6502 in 1976. C64 came out with 1 MHz 6502 in 1982, still it's clear that the C64 is the way better computer.

Uh oh... bashing the 800, 64, Apple, Spectrum and all is okay, but you DO NOT want to piss off the PET fanboys!!!!

Hey, the PET wins the 'Way Cool Futuristic Looking' award hands down. Funny thing is... nobody makes a computer that looks anything like it now.

Edited July 30, 2007 by JamesD

[thomasholzer]

Actually MS Basic 1 and 2 are available for A8 (Yes, I own both).

 

 

>>>>>JamesD say: Yeah, but they weren't an upgraded version of Atari BASIC so they wouldn't run the old code as well as new.<<<<<

 

>>>>>Tom say: Don't do it<<<<<

Not MS Basic, but better:

Turbo Basic XL:

Among the extra features of Turbo-Basic XL, added to ATARI BASIC, are the following:

speed

enhanced sound and graphics commands

more flexible I/O commands, including disk access

structured programming constructs

simple debugging facilities

running stand alone programs

free

 

This was a very popular Basic for XL here in Europe

 

 

 

>>>>>But then the BBC Micro and some Ohio Scientific machines were faster than the Atari.

Also the ZX Spectrum is faster than the Atari.<<<<<

 

So what you're saying is that the C64 is the slowest of the lot!

Edited July 30, 2007 by thomasholzer

[Fröhn]

>>>>>But then the BBC Micro and some Ohio Scientific machines were faster than the Atari.

Also the ZX Spectrum is faster than the Atari.<<<<<

 

So what you're saying is that the C64 is the slowest of the lot!

No, I am saying the the C64 is the slowest when it comes to plain numbercrunching with the CPU. As soon as you do something which relies on the graphic and sound hardware, things can change very quickly. No 8 bit CPU can compensate the lack of VIC-II sprites for example.

[JamesD]

Not MS Basic, but better:

Turbo Basic XL:

Among the extra features of Turbo-Basic XL, added to ATARI BASIC, are the following:

speed

enhanced sound and graphics commands

more flexible I/O commands, including disk access

structured programming constructs

simple debugging facilities

running stand alone programs

free

 

This was a very popular Basic for XL here in Europe

Now imagine how popular it would be if Atari had included it with later machines.

[thomasholzer]

I'm just running 'The Big Demo', Pokey could match Sid easily.

 

 

In Germany, the Atari 8-bit line was the second best selling 8-bit computer, after C-64. Not bad.

 

In UK A8 came third (or second, the Spectrum was a mere calculator).

Edited July 31, 2007 by thomasholzer

[dr_bob]

Just curious , but as a real games machine , did the Atari 8 have many mainstream releases after say 1987 outside the UK /Ireland??

I originally had an atari 800xl , but eventually sold it and bought a 2nd hand c64 around 1988 , basically as there were no new games releases , and no conversions of any of the arcade games I liked(the likes of ghosts and goblins /bombjack etc).

One thing about the C64 is that it seemed to have a much longer life software wise?

[Fröhn]

I'm just running 'The Big Demo', Pokey could match Sid easily.

Uhm if one thing is certain, it's that SID produces far nicer music than POKEY. And what "The Big Demo"? I only found "The B.I.G Demo" for Atari ST, but none like that for A8.

 

In Germany, the Atari 8-bit line was the second best selling 8-bit computer, after C-64. Not bad.

 

In UK A8 came third (or second, the Spectrum was a mere calculator).

You forgot the Amstrad CPC which outsold the A8 in both countries.

 

And concerning the "Spectrum was only a calculator". Wasn't it you who wanted to boil the quality of a computer down to pure CPU power just a few posts earlier? You propably didn't like it when I then said that the Spectrum has more CPU power than the A8

[Gury]

Big Atari 8-bit Demo (from the publishers of Megazine / Pokey disk magazine http://www.pokey.nl/xoops/modules/news/ ):

http://atari.fandal.cz/detail.php?files_id=3503

 

Pokey is great sound chip. I always enjoyed good music made on Atari 8-bit platform.

 

Concerning ZX Spectrum vs A8 CPU power speed. Difference is very small, in most circumstances (with the help of custom chips or without them) A8 outperforms Spectrum.

Edited July 31, 2007 by Gury

[Xebec's Demise]

Even without knowing any of the technical differences, as a kid I thought the Atari was way better. The commodore 64 came in that ugly brown case with rounded edges - the design really looked crummy. Even the name Commodore, reminds me of a Russian dictator or something. But, probably most important was that Atari was a familiar name in the Arcade machines and the games like Pac-man where highly recognized - what kid did not want to have an arcade machine at home. The graphics usually seemed to be better on the Atari games.

 

I guess Commodore won out with better marketing and support?

Edited August 1, 2007 by Xebec's Demise

[supercat]

Uhm if one thing is certain, it's that SID produces far nicer music than POKEY. And what "The Big Demo"? I only found "The B.I.G Demo" for Atari ST, but none like that for A8.

 

One difficulty with the SID is that Commodore changed the behavior of the filter between early and late model C64's. Although the later C64's have technically better filters, the sharper attenuation can cause some music to be a bit squelched. Dragonriders of Pern, for example, sounded better on early C64's than later ones.

[JamesD]

Concerning ZX Spectrum vs A8 CPU power speed. Difference is very small, in most circumstances (with the help of custom chips or without them) A8 outperforms Spectrum.

A 3.5MHz Z80 and a 1.7MHz 6502 are similar in speed. It really depends on whether you write optimal code for one or the other.

One of the big problems with many game ports is that the authors that did the porting may have known one of the processors well and not the other.

If the custom chips start stealing clock cycles on the Atari that also makes a difference. But then the Atari games can look much more colorful and PM graphics really speed up sprite movement in some games.

 

One real advantage of the Speccy was the graphics display. It has a fast layout for writing graphics to the display on games that can't use hardware sprites.

8 bits = 8 pixels and 256 pixels wide... just the the magic width to use 8 bits in width calculations. This makes the math on 3D games simpler and faster than if a 16 bit value is required. The color handling is a bit ugly compared to systems with the same number of colors where you can set the color down to individual pixels but a lot of games make very effective use of it too.

 

To be honest, I think it's a little easier to code on the Z80. You don't have to do theatrics with page 0 to do the same type of things.

However, as a result, I think 6502 coders wrote more optimal code out of necessity from the beginning where you could write downright slow code on the Z80 and get away with it.

But then, on the Speccy forums I've seen really good Z80 coders cut half the clock cycles out of what looks like a pretty efficient routine and it's magazines published some pretty optimal routines for many things back in the day so even beginning programmers could start out with some optimal routines supporting their code. Even if their game logic wasn't optimal they could still push graphics to the display pretty fast.

Edited August 1, 2007 by JamesD

[Gury]

That's true. That's also the reason my second choice would be one of the Spectrums (ZX Spectrum 48K or one of the 128K variations, made later). As mentioned before, CPC is slower in this area, because CPU inside can't compensate optimally for the amount of RAM (16K), which must be handled for displaying the graphics. I am aware of great coders for Z80 CPU, most great software was made for ZX Spectrum, where most afford was put in optimizing the code, making good physics and other behaviours in games.

[carmel_andrews]

Atari hampered the graphics capability by only making ANTIC partially programmable

 

What they should have done is totally open up Antic to be fully programmable, including a feature that was used on the later version of the msx gfx chip, which was reprogrammable graphics modes (incl the resolution), given antic some onboard memory (say betw. 16-32k init. and eventually 64-256k as memory became cheaper) so that you could do more memory based interupt routines (rather then timing/cycle based routines) also re programmable colour pallete (i.e 3 or 4 16/32 bit colour registers or a series of 8bit colour registers, including mixing of colours therefore extending the colour range infinitely) and because antic would have it's own memory and be fully programmable, like the 6502, the memory could also be used for store sprite graphics/data and graphics data and that the only limits for sprites on a screen was only limited by the amount of memory antic had built in

 

Also, since it was Atari's original intention to have the A8 being hardware expandable, if you've ever read the hardware manual (disk or print version) you'll know that the Atari memory map allows for multiple versions of the graphics/sound hardware chip set to exist in the memory map, i think it mentioned about 10 antic chips, 14 GTIA's and god knows how many pokey's

 

Just imagine what sort of capability (hardware wise) such a machine was capable of, and not just a fully programmable Antic chip, apply that to the GTIA and pokey, give them full programmability and also on board memory and for each additional Antic, pokey or GTIA set you have in the system can be programmed to act as a separate hardware system, i.e just imagine an antic/gtia combo that was also capable of hardware blitting, vertical and horiz. screen splitting (hardware) like the STe, Polygon gfx capability, multiple bit planes,unlimited colours, unlimited pmgs on a screen, mip/bump mapping, texture mapping, gouroud shading etc etc and all the gfx capab. of a moden pc/gaming system