Commodore 64 vs Atari 800 Xl

[potatohead]

Yes, indeed! It's flat out amazing that it does anything at all! This makes me very seriously appreciate Batari Basic too. That actually takes the VCS from being one of the most difficult to program for, right down to flat out easy and fun, if limited. I've knocked out a few things with that tool, and just had fun. Damn cool!

I think the best feature of the 2600 is how it was engineered from a purely gaming standpoint from a company that was used to pushing the limits of digital circuits. Game consoles of the era were typically designed to be stripped down cost-reduced versions of normal computing terminal hardware and the 2600 was a totally new approach.

 

I would love to see that kind of work applied to more capable machines.

 

It would certainly be a fun project.

 

Agreed. The 7800 as a target would allow for some kernel variations, leaving the user to build graphic data, take I/O, and populate game loop.

 

Edit: (got interrupted with real work...)

 

The other thing I really like about the VCS is the heavy software driven design. The minimal digital circuit approach is cool in that a lot can happen with very little hardware. But, the fact that the CPU is mixed in there really knocked it out of the park. So many things ended up possible over time that were not at all in the planning and engineering stages. Fact is, bugs enable lots of great displays.

 

Maybe not bugs, just unplanned behavior.

 

The modern Propeller MCU is very similar. You get a small amount of silicon that can generate the color signal, serialize pixels and such, with most of the video residing in a kernel that looks an awful lot like the VCS. That thing went from basic bitmaps and sprites to being able to render WOLF3D, with some objects at speed in PAL. That was not planned at all. It's clear that chip will continue to ramp up for a very long time, ending up producing displays well beyond any initial expectations, just like the VCS did.

 

Recent home brews, Boulderdash, and some of the tech demos being done on VCS, bitmap displays and such are examples of the very same thing, just a different scale.

 

IMHO, doing things that way brings cheap, very useful products that can have considerable variance from their original planned specifications and market differentiators.

 

Grey matter, applied to the silicon over time = great stuff!

 

Back on the topic some, the higher level of hardware assist on VIC, compared to the higher level of CPU on the Atari 8 bits, means rougher development cycles and fewer ports and or lower quality as some of the stuff goes unused. But, it also means more "texture" in the type of display, as well as some room to push the chips in funky directions, arguably where not all of those are productive

 

On the VCS, these things played into it's favor, because the expectations were low, and the hardware actually quite capable. On the A8, it played against it in some ways, because ramping up took time, and the expectations ramped faster than the understanding of how to really run the machine did.

Edited May 11, 2010 by potatohead

[Bryan]

The Propeller stuff sounds like fun.

 

BTW, I would just like to say how thankful I am that certain parties who would normally be attracted to a thread like this have not discovered it.

 

Whether you agree with DimX or not, he's nowhere near as persistent or misinformed as some on AA.

[potatohead]

The Propeller stuff sounds like fun.

 

BTW, I would just like to say how thankful I am that certain parties who would normally be attracted to a thread like this have not discovered it.

 

Whether you agree with DimX or not, he's nowhere near as persistent or misinformed as some on AA.

 

Yeah, I hear that. This discussion weaving around some has been really great. It's got me wanting that SIO device sooner rather than later -->and a 7800 to run stuff on. (Mine is on loan to somebody)

[+remowilliams]

Whether you agree with DimX or not, he's nowhere near as persistent or misinformed as some on AA.

 

Very true and very sad all at the same time.

[oky2000]

And the sprites have a separate palette too, pretty decent design It's a shame Atari split into arcade/home computers really, that sort of technology in R&D would have been very useful to Atari in the mid 80s.

 

It was put in the 7800 instead I reckon the 7800 could do a pretty mean version of Gauntlet.

 

Well I don't know too much about 7800 under the hood, presume you mean best 8-bit version? Maybe, the NES version isn't that well converted, and the SMS version....I suspect someone with technical skills like Probe Software did those graphics. However the ST version is the best in the world as far as home computer conversions go (better than G2 on Amiga or ST), and with a 16mhz 68000 board positively flies.

 

I have Dark Chambers for the XE sealed (well we do have emulators ) but I don't think I have that for the 7800, not sure, my 7800s died a long time ago now sadly.

 

LoL I notice a couple of comments about people not finding this thread, I kinda left it imagining it would just come to a natural halt or get locked, was only reminded of it by Wood_JL in a PM the other day. Don't worry am not here to troll, as you were coders.

 

(although being a coder is only valid if you produce executable code to prove a point, eg a 32 colour anywhere on the screen 160x192 resolution screen mode blah blah, beyond that a person who owns and uses both and has done for decades has just as valid a point to make if your general question is the unanswerable is 'best' like before given both machine designs are compromised, just in very different ways that's all)

[GroovyBee]

Well I don't know too much about 7800 under the hood, presume you mean best 8-bit version?

 

Nope! I was referring to the palette per sprite and the R&D technology. You can have 8 sprites with a different 3 colour palette for each one on the 7800.

 

Maybe, the NES version isn't that well converted, and the SMS version....I suspect someone with technical skills like Probe Software did those graphics. However the ST version is the best in the world as far as home computer conversions go (better than G2 on Amiga or ST), and with a 16mhz 68000 board positively flies.

 

I've never played the NES or SMS versions. I used to play it on the ST tho.

 

I have Dark Chambers for the XE sealed (well we do have emulators ) but I don't think I have that for the 7800, not sure, my 7800s died a long time ago now sadly.

 

Dark chambers is OK on the 7800. The scrolling is very smooth. The 7800 is capable of pushing more baddies on screen than you see in the game. Sacrilege! You have broken 7800s? You should get them fixed immediately .

 

(although being a coder is only valid if you produce executable code to prove a point, eg a 32 colour anywhere on the screen 160x192 resolution

 

You've seen my 169 colour demo on the 7800 then .

[Bryan]

Yeah, I hear that. This discussion weaving around some has been really great. It's got me wanting that SIO device sooner rather than later -->and a 7800 to run stuff on. (Mine is on loan to somebody)

 

Sometime I've got to make up a test board for my PBI Maria board design. Basically, it has a 6502C, a Maria, 32K SRAM (with a 2nd socket to go to 64K), and a 256-byte dual-port RAM so the two CPU's can pass data. It would be a much nicer platform for Maria work than a 7800.

[potatohead]

Now that would be a killer A8 bit upgrade!

[GroovyBee]

Sometime I've got to make up a test board for my PBI Maria board design. Basically, it has a 6502C, a Maria, 32K SRAM (with a 2nd socket to go to 64K), and a 256-byte dual-port RAM so the two CPU's can pass data. It would be a much nicer platform for Maria work than a 7800.

 

If the coprocessor was an ARM then you'd be talking .

[Bryan]

If the coprocessor was an ARM then you'd be talking .

Hmm... I'm going to need a bit more glue logic.

[GroovyBee]

If the coprocessor was an ARM then you'd be talking .

Hmm... I'm going to need a bit more glue logic.

 

The ARM should be able to handle that for you . Check out Harmony/Melody carts on the 2600.

[Bryan]

If the coprocessor was an ARM then you'd be talking .

Hmm... I'm going to need a bit more glue logic.

 

The ARM should be able to handle that for you . Check out Harmony/Melody carts on the 2600.

Ah, I see what you mean. I thought you wanted the ARM free for general use (like... 60fps ray-traced games on the A8).

Edited May 12, 2010 by Bryan

[+SpiceWare]

The ARM should be able to handle that for you . Check out Harmony/Melody carts on the 2600.

I've been working on the ARM demo for the Harmony. Have a 3D wireframe going, updating at 60 fps. There's a quirk in the 3D -> 2D conversion I need to track down. My folks are coming in today from Trinidad for a visit, so it'll be another week before I can get back to it.

http://www.youtube.com/watch?v=wIrbCsqQEi8

[GroovyBee]

Ah, I see what you mean. I thought you wanted the ARM free for general use (like... 60fps ray-traced games on the A8).

 

With the dual port RAM it wouldn't make sense to feed the 6502 instructions like the Harmony board does. Ideally both processors would be left to do their own thing. Faking a limited address and data bus on the ARM is pretty trivial so that it can access the dual port RAM.

[Bryan]

With the dual port RAM it wouldn't make sense to feed the 6502 instructions like the Harmony board does. Ideally both processors would be left to do their own thing. Faking a limited address and data bus on the ARM is pretty trivial so that it can access the dual port RAM.

I'm not sure I follow, although I'm not very familiar with the Harmony cart (other than knowing it uses the CPU to provide bus signals in IO).

 

My plan was to have both CPU's running independently with a shared 256-byte window.

[GroovyBee]

My plan was to have both CPU's running independently with a shared 256-byte window.

Yep! That's what I was trying to say. Except that the one connected to MARIA would be an ARM and not a 6502. If MARIA could access 2 RAM banks such that the ARM can write to one while MARIA reads from the other (and then flip them over if needed) that would be even better.

[Bryan]

My plan was to have both CPU's running independently with a shared 256-byte window.

Yep! That's what I was trying to say. Except that the one connected to MARIA would be an ARM and not a 6502. If MARIA could access 2 RAM banks such that the ARM can write to one while MARIA reads from the other (and then flip them over if needed) that would be even better.

Hmm... that kind of explodes it from a simple project to something I'd probably never get around to (not to mention that throwing an ARM in there kinda offends my retro sensibilities).

Edited May 12, 2010 by Bryan

[GroovyBee]

Hmm... that kind of explodes it from a simple project to something I'd probably never get around to.

 

If MARIA was only creating a 160x192, 4BPP video buffer in RAM having the ability to get the ARM chip to create the whole image in that RAM once per video refresh cycle and then flip it over for MARIA to "read out" on the next would be the best way in my opinion.

 

However, if the 2nd processor is building display lists and getting MARIA to build the screen then flipping video RAM banks isn't really a priority. It depends on what you want to do at the end of the day.

[GroovyBee]

(not to mention that throwing an ARM in there kinda offends my retro sensibilities).

 

The ARM is just the 6502s big brother in my eyes .

[+SpiceWare]

I'm not sure I follow, although I'm not very familiar with the Harmony cart (other than knowing it uses the CPU to provide bus signals in IO).

Yep - the ARM drives what the 6507 sees on the bus. Batari set it up so when an ARM subroutine is called, the ARM puts NOP on the bus so the 6507 doesn't do anything while the subroutine is processing. It then stuffs a JMP onto the bus to put the 6507 back to the command that follows the ARM subroutine call.

[Garak]

The ARM is just the 6502s big brother in my eyes .

 

Perhaps that should be little brother since ARM was 'born' after the 6502.

[GroovyBee]

Perhaps that should be little brother since ARM was 'born' after the 6502.

 

True! But I could also have meant that the ARM had been pumping iron for some time too .

[sack-c0s]

I grew up with an archimedes when most people were fighting the ST/Amiga wars, so ARM still feels retro to me

Edited May 13, 2010 by sack-c0s

[oky2000]

I grew up with an archimedes when most people were fighting the ST/Amiga wars, so ARM still feels retro to me

 

 

Quite lucky really, read about them in ACE magazine in the 80s. I liked them but as Zarch and Lotus II were the only games on it I wanted to play, and one of those looked the same on the Amiga, I really couldn't justify the price. And then a few years ago when loads of schools had dumped their old stock and they ended up on ebay there was hardly any games to be found for sale or download.

 

Pretty rare machine now.

[TMR]

And then a few years ago when loads of schools had dumped their old stock and they ended up on ebay there was hardly any games to be found for sale or download.

 

Pretty rare machine now.

 

Schools dumping stock is why i've got an A3010, two A5000s and two A7000s... i want to set one of the latter up but it needs the operating system reinstalling and my current "project" on that front is trying to get the A600HD i was given at Retro Reunited booting from a CF card...