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

[neuromancer]

Thx neuromancer, you are welcome to visit my site anytime. Which Atari do you own? I have 130XE with SIO2PC installed and 1050 disk drive. I will go for more stuff soon, I want to join all Atari collectors worldwide

I also have a 130XE and 1050 drive - somewhere along the line the psu's for both have gone awol - I will track them down though...

I have a soft spot for the original Atari 400 - when I was much younger a friend's dad had one - compared to my ZX81 it was one hell of a machine. He had a replacement fully-moving keyboard for it. A few years later he moved to Germany for a couple of years where the Atari scene was massive. As a result I got access to a stack of demos and games

[neuromancer]

I use Spin to emulate the speccy. Is it generally considered to be accurate?

I've not used that one - I think the litmus test is to run Uridium on it and see if it renders the multi-colour trickery correctly...

[necronom]

As soon as I saw the first post mentioning Uridium, I had a look on ZX Spin and didn't see anything impressive, then I tried Klive, and it worked as it's supposed to.

I wonder how he broke the colour limit. Clever.

[Arjun]

ZX Spin is one of the most accurate speccy emulators for windows out there. Period.

[neuromancer]

ZX Spin is one of the most accurate speccy emulators for windows out there. Period.

Seems there's a bit of contention on this one - can Spin accurately emulate those Uridium effects?

[neuromancer]

As soon as I saw the first post mentioning Uridium, I had a look on ZX Spin and didn't see anything impressive, then I tried Klive, and it worked as it's supposed to.

I wonder how he broke the colour limit. Clever.

There was a type-in listing in YS which claimed to break the 2 colours per 8x8 block limit; I typed the whole, long, tedious list of machine codes in via the loader and was so eager to see it in action that I ran it without saving (what on earth was I doing? I'd had enough experience of my ZX81 crashing at random to know better by the time I had a speccy)

Needless to say it didn't work - I lost the whole thing.

I typed it in again, saved it, ran it - watched it crash...

I found that edition of YS in the loft at my parent's house last week - there were annotations on the listing where I'd double and tripple checked everything I'd typed.

I've always wondered if it was some demented joke, or if it only worked on certain issues of speccy. I never saw and corrections printed in later issues of YS.

If anyone can shed any light on this my sanity would benefit!

[andrew_rollings]

ZX Spin is one of the most accurate speccy emulators for windows out there. Period.

Seems there's a bit of contention on this one - can Spin accurately emulate those Uridium effects?

Yes, and then some.

[Matt_B]

The basic trick to multicolour rendering on the Spectrum is changing the attributes between scanlines. Then, the next time the ULA reads them for the following line, you'll get different colours. Because it's so timing critical, it's really hard to get it working inside an action game where code will take different amounts of time to execute depending on the exact state of things.

It's pretty easy to get good results with static screens though and this is used in a lot of games. I even managed to work a 25 byte routine into my 1K minigame Deathrider that puts coloured stripes across the title logo whilst it's waiting for a game to start.

Spin does support multicolour rendering, but I belive it's turned off by default as few games use it and it's rather processor intesive.

[neuromancer]

The basic trick to multicolour rendering on the Spectrum is changing the attributes between scanlines. Then, the next time the ULA reads them for the following line, you'll get different colours. Because it's so timing critical, it's really hard to get it working inside an action game where code will take different amounts of time to execute depending on the exact state of things.

It's pretty easy to get good results with static screens though and this is used in a lot of games. I even managed to work a 25 byte routine into my 1K minigame Deathrider that puts coloured stripes across the title logo whilst it's waiting for a game to start.

Spin does support multicolour rendering, but I belive it's turned off by default as few games use it and it's rather processor intesive.

Thanks Matt_B, that's interesting stuff.

I'm currently learning some z80 assembler (arriving via a tortured path including various 8bit basics-> vfp-> java-> c#-> c ->z80 assm)

I've got a number of books but they're all stuck at the same level (either 'introducing' or hardcore detailed (rodney zaks)) - it's difficult to find books that explain how to achieve various effects. Not so hard with the atari 8bit - the books are there (if you have the money...)

[OriginalJax]

I've got a number of books but they're all stuck at the same level (either 'introducing' or hardcore detailed (rodney zaks)) - it's difficult to find books that explain how to achieve various effects. Not so hard with the atari 8bit - the books are there (if you have the money...)

While a lot of 'tricks' are portable across machines sharing the same processor, they are generally restricted to things like fast approximation of a square root, or other algorithms. The 'tricks' alluded to in this thread (and those elsewhere) are largely hardware-dependent, so researching those will require detailed hardware documentation (right down to hardware timing diagrams, in some cases) or access to Spectrum source code with a description of what they're doing, and why.

O-Jax

[necronom]

Spin does support multicolour rendering, but I belive it's turned off by default as few games use it and it's rather processor intesive.

Yes, it was switched off. I found the option, and it works now.

[Pengwin]

Out of the four options here, I would have to vote spectrum (and i did). However, I agree with Gury, the Atari 8-bit range were and still are great machines, way ahead of their time when they first emerged.

[TMR]

The basic trick to multicolour rendering on the Spectrum is changing the attributes between scanlines. Then, the next time the ULA reads them for the following line, you'll get different colours. Because it's so timing critical, it's really hard to get it working inside an action game where code will take different amounts of time to execute depending on the exact state of things.

If memory serves, some more complex timing jobs vary between different models of Spectrum as well...?

The same trick should be possible on the VIC 20 (although with a slower CPU and very little memory to unroll the code into... still, at least the chars are wider!) as well but doesn't work on the C64 or Plus/4 without the use of Flexible Line Interpretation or a variant due to the way the VIC-II and TED chips work for fetching colour. Y'can't really do it on an Atari 8-bit because they don't have colour memory (you can split at least some of the five colours you get on a per scanline basis easily enough though) whilst the BBC and CPC use palette-based screens and don't have to worry about attribute cells. =-)

[Emperor Fossil]

Spin does support multicolour rendering, but I belive it's turned off by default as few games use it and it's rather processor intesive.

Yes, it was switched off. I found the option, and it works now.

Allrighty. I guess I'll stick to spin...


...when I'm not basking in the glory of the c64 in vice64x, that is.

[oswald]

Some nice static images, but that seems to be about it.

not those are ingame shot of many 50fps games. maybe show something similar your machine can do instead of telling us stories about your imaginary c64 friend. but you will fail to do that.

Lol! You've missed the point here. All the machines here can do nice piccies, but that's hardly going to prove the worth of the machine. That's just childish. So is trying to prove how good a game is by showing a few screen grabs. Don't be daft.

For Speccy greatness, try:

Ant Attack (Cuz the C64 one was just so darn'ed clunky)
Aliens (Oozing atmosphere, and closer to the film)
Elite (It doesn't flicker and its got new missions!)
Cybernoid II
Egghead entertains
Oracle's Cave
Trashman
Skooldaze
Chase HQ


My favorite C64 games:

Forbidden Forest
Eidolon (The best port of this game me finx)
Paralax

too bad for you that for the c64 commercial games were produced till 94-95... at the final years the c64 competed with the pc and amiga platforms, at that time the days of speccy/beeb/cpc/atari were over since LONG years. the list of your speccy greatness games has games that on the c64 are considered as crap since we had much better ones...

if it comes to what do you *think* which was the better machine, you are free to *think* speccy, beeb, or cpc was. however any objective comparison brings out c64 as the best by far. (lifespan, number of available games, nr of machines produced, price/performance ratio, best available games, whatsoever)

"All the machines here can do nice piccies, but that's hardly going to prove the worth of the machine."

its so pathethic when you pretend you dont understand my arguments. the c64 can do piccies be it static / non static that outclasses any other 8 bits. The c64 has games that look better and play better than any other 8 bits, the c64 can display static pics that are lightyears nicer than any other 8 bit platforms. The c64's today active userbase are 100x bigger than any other 8bits. For what I know here in hungary you cant find a single man at age 20-35 who doesnt knows what a c64 is, but and thats the same for most euro countrys I bet, while I would be suprised if anyone knew about the beeb/cpc/atari. More ppl had speccys, but anyone who wanted a decent gaming machine used a c64 at 85-90 here.