Poll: Better graphics -- Hardware upgrade development

[+CharlieChaplin]

Hmmm,

think i have heard about this GTIA and Antic upgrade years before. Someone told me it was written by Chuck Steinman (the same guy, that wrote an article about the Pokey/Gumby upgrade for stereo sound) and appeared in Atari Classics. Alas, I don`t have any AC magazines, so I could never read that article and I have not found it online yet.

 

But, like the Pokey upgrade this Antic/GTIA upgrade should have been done internally - inside the machine, not via the parallel bus. remember: only the 600XL and 800XL machines do have them. The XE (alas not all XE`s, only some of them!) do have the Cart.port+ECI port which almost does the same job as the XL parallel bus. But this means, one would have to develop two different upgrades: one for XL type computers and one for XE type computers. and there would still be some Atarians left alone (those who merely have 400/880 computers and those who merely have Xe`s without ECI port)...

 

So, why not thinking about an internal upgrade ?!? Maybe one can piggy-back the additional ANTIC and GTIA chips right on the already existing ANTIC and GTIA chips and then do some wiring inside the computer... Personally, I think this is a great project. But it should be possible to "do-it-yourself". If one can only BUY your upgrade, then it will not have much chance... So maybe you can a) sell the upgrade on a pcb and b) also give details, plans and schematics (as well as programming hints and tips), so anyone can do it alone/at home... Ok, just some thoughts. Hopefully, they were not too negative. Besides, I am still interested in that article (maybe from Chuck Steinman, maybe appeared in AC...) that explains on how to install a second Antic and GTIA into your Atari computer... greetings from ABBUC, Andreas Magenheimer.

[+CharlieChaplin]

Just a small reminder:

- atari 400: no parallel bus !

- atari 800: no parallel bus !

- atari 1200XL: no parallel bus!

- atari 1400XL: not sure ?!? (probably no parallel bus!)

- atari 1450XLD: not sure !?! (the built-in floppy uses the parallel bus!)

- atari 65XE : some with & some without ECI port

(of course no XL parallel bus !)

- atari 130XE: has cart. port and ECI port !

(which can be used as an XL parallel bus)

- atari 800XE: some with & some without ECI

(no XL parallel bus!)

- atari XEGS: no parallel bus...

 

whereas:

- atari 600XL: has parallel bus !

- atari 800XL: has parallel bus !

 

From this point of view, the parallel bus graphic upgrade doesn`t sound so good or does it ?!? Anyway, it is a good project !! greetings, Andreas Magenheimer.

[+CharlieChaplin]

Just a small reminder:

- atari 400: no parallel bus !

- atari 800: no parallel bus !

- atari 1200XL: no parallel bus!

- atari 1400XL: not sure ?!? (probably no parallel bus!)

- atari 1450XLD: not sure !?! (the built-in floppy uses the parallel bus!)

- atari 65XE : some with & some without ECI port

(of course no XL parallel bus !)

- atari 130XE: has cart. port and ECI port !

(which can be used as an XL parallel bus)

- atari 800XE: some with & some without ECI

(no XL parallel bus!)

- atari XEGS: no parallel bus...

 

whereas:

- atari 600XL: has parallel bus !

- atari 800XL: has parallel bus !

 

From this point of view, the parallel bus graphic upgrade doesn`t sound so good or does it ?!? Anyway, it is a good project !! greetings, Andreas Magenheimer.

[+CharlieChaplin]

Just a small reminder:

- atari 400: no parallel bus !

- atari 800: no parallel bus !

- atari 1200XL: no parallel bus!

- atari 1400XL: not sure ?!? (probably no parallel bus!)

- atari 1450XLD: not sure !?! (the built-in floppy uses the parallel bus!)

- atari 65XE : some with & some without ECI port

(of course no XL parallel bus !)

- atari 130XE: has cart. port and ECI port !

(which can be used as an XL parallel bus)

- atari 800XE: some with & some without ECI

(no XL parallel bus!)

- atari XEGS: no parallel bus...

 

whereas:

- atari 600XL: has parallel bus !

- atari 800XL: has parallel bus !

 

From this point of view, the parallel bus graphic upgrade doesn`t sound so good or does it ?!? Anyway, it is a good project !! greetings, Andreas Magenheimer.

[+CharlieChaplin]

Oops,

whats that ?!? My computer gave me an error when posting the message, so I posted it again and again, until it worked. and now I see the posting is there 3 times ?!? Sorry for that ... -Andreas magenheimer.

[Goochman]

Well B&C has new 800XL's for $100 - maybe we could get a packaged deal, $150 for a 800XLDGAP (Double Gtia Antic Pokey )

 

Therefore no hacking up our existing stock!

[Shawn Jefferson]

The 1400XL and XLD have parallel buses, but I don't think you need worry about people trying to run a double GTIA/ANTIC combo in those models particularly.

 

Can't someone offer a send in your computer and get GTIA/ANTIC installed service? They could do ram upgrades and stereo sound upgrades at the same time as well. Although that might eat up a lot of power...

[Thelen]

I think that the main problem is, that a complete board won't fit inside an XL or XE machine. and not all people can solder and wire (lot's of wires - I'm getting sick of soldering wires ) the whole thing up (without any faults). I think an external board is a great idea, you don't have to modify your atari (or really small things), and you can swap the unit !

 

Thelen

[analmux]

@ CharlieChaplin

 

Hmmm, think i have heard about this GTIA and Antic upgrade years before.

 

That's possible, but it might be different from this upgrade (without its own RAM perhaps?), because I found it out by myself one year ago.

 

...this Antic/GTIA upgrade should have been done internally

 

That was my first plan, but there is not much room left for it, cause it's a big board, and you must solder 50 wires to it, so the best way would be socketing, so the electric screening must be partially removed, but not every Atari has sockets. So there are lots of problems. Another way is a PB-device, although it would still need about 12 wires that are not mapped through the parallel-bus.

 

But this means, one would have to develop two different upgrades: one for XL type computers and one for XE type computers.

 

We are working on different types of PB-devices. One for XL and one for XE. Another solution (for the needed data and addresslines) could be the cartrigde port, but now we're aiming on the Parallel bus.

 

So, why not thinking about an internal upgrade ?!? Maybe one can piggy-back the additional ANTIC and GTIA chips right on the already existing ANTIC and GTIA

 

There's practically no room left above the Antic and Gtia, and an internal board can carry the risk of overheating.

 

But it should be possible to "do-it-yourself".

 

Well its a lot of work to do it yourself. You'd have to be very disciplined. But as soon as it is ready I will publish the full schematics and How-To-Install's on the net, but not everyone can produce board-prints themselves. You'd need a Ultra Violet lamp and some chemicals, and you must work with great care. Then you must drill 200 holes and solder 200 connections between the front and back side. But it is not impossible.

 

When people want to make the upgrade themselves partially, I'd love to only send them the bold boardprints, so they can solder the components on it theirselves.

 

When it's ready I'll also publish a detailed FAQ on programming the board, and connecting it to the computer.

 

Hopefully, they were not too negative.

 

No, they aren't. In the contrary, I think your questions are needed to clear things up (when I answer them ).

 

 

@ Shawn Jefferson

 

Can't someone offer a send in your computer and get GTIA/ANTIC installed service? They could do ram upgrades and stereo sound upgrades at the same time as well. Although that might eat up a lot of power...

 

We are now considering to offer an installation service, although we would do no Ram or Pokey upgrades, only double GTIA+ANTIC.

 

 

@ Thelen

 

I think an external board is a great idea, you don't have to modify your atari (or really small things), and you can swap the unit !

 

Yes indeed. But this should not grow bigger than just a hobby project, so we will only make the unit for people who have an Atari WITH parallel bus. Later we will consider making an alternative board that can be installed inside an Atari, for people that want to decide themselves how to install and use it.

 

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mux

[analmux]

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I must clear one thing up:

 

Because the parallelbus doesn't provide all the needed signals, there MUST be installed an extra connector, like an LPT-port. This can be done (by yourself) much more easy. But we will offer an installation service for the additional connector. It will be made on the backside, just above the parallelbus.

 

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mux

[analmux]

Another solution (for the needed data and addresslines) could be the cartrigde port

 

We might reconsider the way of connecting the unit. Because almost every Atari 8bit has a CP (=cartridge port), and the CP gives the needed signals too, it would be no problem to connect the unit to the CP instead of the PB (=parallel bus). Now we don't have to worry about the different PB's of the XL/XE anymore. Besides, the PB on an Atari 130XE IS in fact a cartridge port, with some extended pins, so we can save us the trouble and go for the cartridge. The additional connector though would still be needed.

 

Then, the unit could have a second connector on top to be able to use cartridges or IDE-controllers rewired through the unit.

 

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mux

[Goochman]

Maybe look at supporting the MyIDE cartridge already out there?

[Tickled_Pink]

What an amazing project. I must confess to have thought about this sort of thing for years.

 

At one time I tinkered around with the prospect of converting ST games to the 8-bit. I even managed to use graph paper to create a very neat 'Bubble Bobble' intro screen by copying the ST's intro, and also did a similar job with Xenon's sprites and in-game graphics. But they obviously lacked colour.

 

Now, with this upgrade I could make a near identical copy of ST game graphics ... cool!

[TMR]

Now, with this upgrade I could make a near identical copy of ST game graphics ... cool!

 

Well, you're going to be sacrificing a little resolution (320x200 to 160x200) so i wouldn't have said identical as such... =-) Why didn't you go ahead anyway, Xenon doesn't have to be all that colourful and the C64 graphics are an easy port away...?

 

i've just had a thought, what this hardware needs is emulator support; that way people without could enjoy the software and people who develop but don't have it can at least build software...?

[emkay]

 

i've just had a thought, what this hardware needs is emulator support; that way people without could enjoy the software and people who develop but don't have it can at least build software...?

 

For development on an emulator it would be useful to have at proper working one... don't you agree? By the technical solution Analmux uses, I think a "special Timing" would be necessary.... wasn't "special timings" a problem of every 8-bit emulation...?

 

Btw: What about your developing on the emulator ?

Any chance to see a final Intro/Demo/Game?

[TMR]

For development on an emulator it would be useful to have at proper working one... don't you agree? By the technical solution Analmux uses, I think a "special Timing" would be necessary.... wasn't "special timings" a problem of every 8-bit emulation...?

 

Ah, i'm used to emulators that are cycle perfect like the two main C64 ones are. But yes, an emu would have to be accurate before it could have an implementation of the hardware onboard so that's one less avenue available to promote the new kit. =-(

 

Btw: What about your developing on the emulator ?    

Any chance to see a final Intro/Demo/Game?

 

The first intro gets released in the next day or so, it's a small intro advertising C.G.M. UKScene Radio and is being released on both the Atari and C64. At the same time, 4-Mat's Bad Scene Poetry on the VIC20 is being uploaded (and that's bloody awesome!). i've got a few demo effects together for something a bit bigger but i'm technically in "game mode" right now so they're on the back burner with game projects getting priority.

 

Reaxion A8 is still on the go too; all game code is up and running (i haven't spotted any bugs but i'm not declaring it 100% just yet), the presentation side of the titles page is half done and Sack has sent a preview of the ingame music over. The highscore processing (a job i utterly hate!) has yet to be done along with tweaks to add a new font for credits and scroller on the titles page and the completion sequence has yet to be coded but i've just had a lot on recently with C64 code, life (the kids are off school so i've been busy with them) and i accidentally ended up learning the Nintendo NES a few nights back... =-)

[TMR]

Okay, all officially released and available to download from www.cosine.org.uk (with a new Atari 8bit demos section to boot! =-)

 

As i said up there, we've put out the C.G.M. UKScene Radio Intro for Atari 8bit and C64 (code and graphics by me, music by Sack) and at the same time released Bad Scene Poetry, an unexpanded VIC20 demo by 4-Mat. Enjoy and thanks to Heaven for crunching the Atari code down for me... =-)

[analmux]

Okay, I'm off to university the coming period, very busy. I think the betaversion of the graphics unit will be finished and tested in about six weeks. So expect more then.

 

@ TMR

 

i accidentally ended up learning the Nintendo NES a few nights back... =-)

 

Cool, I'm working on a NES project now. Trying to make a very hard Mario 2 & 3 version. I just managed to change the leveldata of both games. Also some changes in the enemydata (positions in the level, and type of nasty). Mario 2 will get more levels, I found a big amount of free space in the ROM image. Mario 2 also has space left for 2 more sprite-graphics sets and 2 more character-graphics sets.

 

I change all data, but not the code though.

 

Now I figured the leveldata of both games out, there might be a chance that I port the 2 games to atari 8bit (maybe next year), using lots of MCS and software sprites.

 

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mux

[TMR]

Cool, I'm working on a NES project now. Trying to make a very hard Mario 2 & 3 version. I just managed to change the leveldata of both games.

 

The NES is a git to code for, the screen handling especially is a pain in the bum and only getting 8 sprites on a row before it starts to flicker is pretty nasty too (each sprite is 8x8 pixels, so four reasonably sized 16 pixel objects a line is the max before there are issues).

 

i expect Reaxion NES has already wormed it's way onto my mental "products in progress" list... =-)

[analmux]

@ TMR

 

The NES is a git to code for

 

I know, that's why I do not waste any time to code it

 

the screen handling especially is a pain in the bum

 

I thought it's the easiest screen to handle on an 8bit. The screen wraps perfectly while scrolling, according to my experience.

 

and only getting 8 sprites on a row before it starts to flicker is pretty nasty too

 

Are they multiplexed (on different rows) by hardware, or by a raster interrupt (I suppose the NES must have a raster-interrupt).

 

If you play (f.e. world 4-2 of) Super Turrican on NES, you sometimes see more than 16 enemies (with a res. of 16*16 pixels) on a screen at the same time.

 

By the way, there are 2 types of sprites on the NES: 8*8 and 8*16 pixels.

 

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mux

[Tickled_Pink]

Now, with this upgrade I could make a near identical copy of ST game graphics ... cool!

 

Well, you're going to be sacrificing a little resolution (320x200 to 160x200) so i wouldn't have said identical as such... =-) Why didn't you go ahead anyway, Xenon doesn't have to be all that colourful and the C64 graphics are an easy port away...?

 

If I remember the specs of this project correctly (too lazy to look it up), it gives 16 colours in 320 x 192 which is almost identical to the specs of the ST in lo-res mode (16 colours in 320 x 200 - just a few scanlines short).

[Tickled_Pink]

Forgot something that's bugging me about this project. I still can't get my head around how it'll work in practice.

 

Okay, you have an extra Antic/GTIA and some dedicated memory. Someone has probably tried to explain this before but ... why won't programs slow down? Surely the dedicated RAM has to be filled, which will take extra time. Or is there something really clever happening?

[analmux]

@ Tickled_Pink

 

You're right:

 

There are two sources of speed-decrease:

 

-DMA which is cleverly filtered away by the separated bus.

-twice as much screendata to handle (this is what you mean).

 

Think of a charmode game with PM. Normally you have to worry about ±1 kb of screendata and 1280 (fine) or 640 (course) bytes PM-data.

 

With the upgrade unit it will be twice as much, and will indeed need twice as much time to handle.

 

But with clever DL-techniques and PM-engines you can reduce the amount of bytes to be handled to 80 (for the screen, with wrapped scrolling), and say 129 or 256 (for the PM-data) every frame.

 

It can hardly be a problem.

 

Remember that all the clever 6502 routines for generating more colours (DLIs and especially horizontal kernels) can be thrown in the thrash now, because you already HAVE many colours.

 

About the 320*192 mode: it will only provide a special palette: this means 16 colors in 2 different shades.

 

Colors form circuit 1 are mixed (like PM color ORring) with luminances from circuit 2. So there are just 2 lums and 16 colors. The 16 colors are not free choosable. I'll give some examples of HiRes soon.

 

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mux

[TMR]

I thought it's the easiest screen to handle on an 8bit. The screen wraps perfectly while scrolling, according to my experience.

 

The main problem is writing to it, the memory for the screen is two banks of 64K away from where the program ROM and RAM is so it's all done by writing to a couple of control registers. If you want to write ten bytes to $2020 (assuming your screen starts at $2000) you have to write $20 and $00 to a control register and then feed the ten bytes to a second register one at a time.

 

What's really nasty is that you can't do any of these changes during the display as far as i can tell, so you have to do everything in little chunks between the start of the vblank and the start of your actual screen. Writing to the RAM up where the screen is also messes up the smooth scrolling vectors so they need resetting too!

 

Are [NES sprites] multiplexed (on different rows) by hardware, or by a raster interrupt (I suppose the NES must have a raster-interrupt).

 

There are just 64 sprites available and you can put them wherever you want them (the first thing i did was put them all on screen at slightly different heights and move them a bit) but if more than 8 try to exist on the same rasterline only the lowest eight appear.

 

i've not found a raster interrupt yet, it just seems to know when it's vblank has happened.

 

If you play (f.e. world 4-2 of) Super Turrican on NES, you sometimes see more than 16 enemies (with a res. of 16*16 pixels) on a screen at the same time.

 

If 8x16 mode is used, that's 32 possible 16x16 pixels objects available. There'll still be a limit of eight sprites on a row in that mode, though.

[analmux]

...If you want to write ten bytes to $2020 (assuming your screen starts at $2000) you have to write $20 and $00 to a control register and then feed the ten bytes to a second register one at a time.

 

Off course. The Video Chip of the NES has its own RAM (4 or 8 kbytes I think) and the chip doesn't halt the CPU.

 

It's a bit like my extension unit. The Video Chip has a separated circuit. It even has it's own ROM chip (VROM), separated from the program ROM (PROM). The VROM contains all the character and sprite shapes. So there is no way to change characterdata on screen (for f.e. software sprites). Look at Super Turrican's parallax in level 3-1. It doesn't shift the bytes (like C64's Turrican II in level 3-1) but it's pageflipping between fonts. A nice thing about the NES is that it can have 4 redefinable fonts at the same time (the same applies for the spriteshapes).

 

The NES video can show 256 different characters BUT it has 4 blocks of 64 characters that can independently chosen from the VROM (4 blocks of 1kByte) Note: every character (8*8 pix) needs 16 bytes.

 

 

What's really nasty is that you can't do any of these changes during the display as far as i can tell

 

I think it's related to the DMA of the video chip. Though the Video chip has its own bus, it does need it fulltime on graphics fetch. The CPU isn't halted, so could write (via the control-registers and ports) to the VRAM (the video chip's own RAM) which leads to a bus conflict.

 

Have you ever looked at some code of a NES game? It has a NMI vector on $FFFA so it certainly has a VBlank (or similar) interrupt.

 

Look at the ROM of Super Mario Bros. It's 32 kbytes Program, and 8 kbytes graphics. The program is mapped from $8000-$FFFF (I think).

 

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mux