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#151 atariksi OFFLINE  

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Posted Sun May 16, 2010 4:11 PM

You sure you understand the idiom that "it doesn't hold a candle". Take another example: Atari 800 doesn't hold a candle to Pentium IV PCs. That means that you can still have a few things that Atari 800 has superior to modern PCs (like fastboot, better joysticks, etc.) and still that statement is true. GroovyBee is wrong and you are too for agreeing with him. Sorry, but just biasing a machine for a certain hardware aspect doesn't make it superior. It doesn't hold a candle to so many other features of A8 which NES and other 8-bit consoles lack.


I understand that and YOU can stop being so condescending. The feature line items the A8 had over the NES were basically irrelevant to the hordes playing the SMB series, Kirby series, and other well regarded franchises on the title. My point was the NES was very good at such games and developing them was relatively easy. Can the A8 be cudgeled into doing such a game? Sure, but it isn't easy or quick and the results are debatable. We basically have Crownland and a small handful of other titles to hold up in that regard and the number will stay small because the limited talent and expense pool for creating them probably isn't going care about the no doubt voluminous feature list you'll reply to this with.
...

Are we talking about the same point here-- doesn't look like it. When you compare a computer system with a console, the computer automatically gets a whole bunch of advantages so even with you more tiles or another channel or two of sounds don't hold a candle to what the A8 can do. A8 is well-rounded in terms of its computing capabilities whereas NES and some others like 7800 are stressing just sprites or tiles. NES has very little RAM, no scanline based IRQs, no WSYNC, serialized joystick ports, less colors, very little sprite collision/priority registers, NO KB/Disk drive, etc. etc. Doesn't matter if you can build a few games targetting its strengths that show up a little better.

The NES IS superior for big-world tile based games and those were the "killer apps" for the console. To be sure, the A8 has it all over the NES for Ballblazer but Ballblazer wasn't what was making the NES a hit. The A8 can no doubt show some superiorities in other areas but so what? They aren't terribly relevant to type of gaming that started predominating in the mid eighties.

And while I'm on the point of "quick and easy", the A8 can truly do some astounding things in the hands of a super talented developer even things that aren't easily replicated elsewhere. But to middle of the bell curve devs, the A8 doesn't yield it's treasures easily or quickly and platforms like the NES did.
...

It's the reverse; it's the middle of the bell curve applications/games where A8 wins. See explanation above. A8 shows the major strengths; NES is good just for a few games biased towards its tiles. And that cartridge connector isn't a big thing either. Stressing one aspect of the hardware and then claiming it superior over A8 is the exact faulty logic that I was disputing.

#152 atariksi OFFLINE  

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Posted Sun May 16, 2010 4:13 PM

That Sync line isn't on Atari's 6502s, at least not the Sally version.


The 68000 isn't getting those idle cycles getting used freely either-- there's some logic involved. My point was the bus usage and 6502 is more optimal in using its bus but 68000 clock speed is higher so it makes up for those inefficient bus cycles.

#153 Rybags OFFLINE  

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Posted Sun May 16, 2010 6:41 PM

It allows other devices to use the bus on otherwise idle cycles without stalling the CPU, which the 6502 doesn't do.

Otherwise, the ST would effectively run at 4 MHz, where in reality it only has 50% of the bus cycles given to it but doesn't suffer anywhere near a 50% throughput penalty.

#154 philipj OFFLINE  

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Posted Sun May 16, 2010 7:51 PM

You sure you understand the idiom that "it doesn't hold a candle". Take another example: Atari 800 doesn't hold a candle to Pentium IV PCs. That means that you can still have a few things that Atari 800 has superior to modern PCs (like fastboot, better joysticks, etc.) and still that statement is true. GroovyBee is wrong and you are too for agreeing with him. Sorry, but just biasing a machine for a certain hardware aspect doesn't make it superior. It doesn't hold a candle to so many other features of A8 which NES and other 8-bit consoles lack.


I understand that and YOU can stop being so condescending. The feature line items the A8 had over the NES were basically irrelevant to the hordes playing the SMB series, Kirby series, and other well regarded franchises on the title. My point was the NES was very good at such games and developing them was relatively easy. Can the A8 be cudgeled into doing such a game? Sure, but it isn't easy or quick and the results are debatable. We basically have Crownland and a small handful of other titles to hold up in that regard and the number will stay small because the limited talent and expense pool for creating them probably isn't going care about the no doubt voluminous feature list you'll reply to this with.
...

Are we talking about the same point here-- doesn't look like it. When you compare a computer system with a console, the computer automatically gets a whole bunch of advantages so even with you more tiles or another channel or two of sounds don't hold a candle to what the A8 can do. A8 is well-rounded in terms of its computing capabilities whereas NES and some others like 7800 are stressing just sprites or tiles. NES has very little RAM, no scanline based IRQs, no WSYNC, serialized joystick ports, less colors, very little sprite collision/priority registers, NO KB/Disk drive, etc. etc. Doesn't matter if you can build a few games targetting its strengths that show up a little better.

The NES IS superior for big-world tile based games and those were the "killer apps" for the console. To be sure, the A8 has it all over the NES for Ballblazer but Ballblazer wasn't what was making the NES a hit. The A8 can no doubt show some superiorities in other areas but so what? They aren't terribly relevant to type of gaming that started predominating in the mid eighties.

And while I'm on the point of "quick and easy", the A8 can truly do some astounding things in the hands of a super talented developer even things that aren't easily replicated elsewhere. But to middle of the bell curve devs, the A8 doesn't yield it's treasures easily or quickly and platforms like the NES did.
...

It's the reverse; it's the middle of the bell curve applications/games where A8 wins. See explanation above. A8 shows the major strengths; NES is good just for a few games biased towards its tiles. And that cartridge connector isn't a big thing either. Stressing one aspect of the hardware and then claiming it superior over A8 is the exact faulty logic that I was disputing.


It would seem like that a computer would be better structured then a game console just made for sprite animation... Considering the times, most of the arcades were mostly sprite based machines, not including the vector arcades, thus defined what was needed to make video games during that time. Game systems like the NES were task specific graphics and sound computers to produce a certain product, which were the sprite based video games, that sold very well during that time. But the A8 computers seemed more flexible then an NES because of it's well rounded system design. Keep in mind that video game crash, due to an over satuation of sprite based games, made sprites the norm/industry standard; so for sprite based games the NES served its purpose. But to me it seems like the A8 (as you-all call them) has more flexibility especially when you consider how much more RAM it had over the NES. That alone seems like it would've gave some kind of graphical momentum over the NES even though it couldn't display sprites and tiles as fast as an NES. 64K is a lot of RAM compared to 2K was it the NES sported?

#155 Keaton Blue OFFLINE  

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Posted Sun May 16, 2010 8:25 PM

A find this all very exciting! Especially as a musician I can see the benefits of a lot of this! I'm very curious about AMY sound chips and new quad POKEYs. Would it be possible to modify the POKEY to get rid of the detuning problem on a hardware level?

#156 atariksi OFFLINE  

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Posted Mon May 17, 2010 5:11 AM

It allows other devices to use the bus on otherwise idle cycles without stalling the CPU, which the 6502 doesn't do.

Otherwise, the ST would effectively run at 4 MHz, where in reality it only has 50% of the bus cycles given to it but doesn't suffer anywhere near a 50% throughput penalty.


Not really. If I have Move D0,$4D, it takes 4 cycles for opcode fetch (2 actually use the bus and 2 are internal operations or do nothing), 4 cycles for operand fetch, and 4 cycles for read from location $4D. On 6502, it would be LDA $4D which is 1 cycle for opcode fetch, 1 cycle for operand fetch, and 1 cycle to read from location $4D. So 68000 takes 12 cycles but some external chip like a DMA controller which is synched up with the 68000 can utilize the second of the 2 cycles for each of the 4 cycles for another bus cycle. So even in this case, it's not as effective as 6502 which automatically optimized the bus usage. The 6502 instructions like TAY, TYA, etc. which do not need bus on 2nd cycle can be further optimized by some external chip to use that second cycle for DMA or coprocessing although they didn't put such a chip in on Atari 800. Also, there are exceptions on 68000 where the second 2 cycles aren't available and 68000 has to be halted and delays the instruction execution.

#157 atariksi OFFLINE  

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Posted Mon May 17, 2010 5:20 AM

You sure you understand the idiom that "it doesn't hold a candle". Take another example: Atari 800 doesn't hold a candle to Pentium IV PCs. That means that you can still have a few things that Atari 800 has superior to modern PCs (like fastboot, better joysticks, etc.) and still that statement is true. GroovyBee is wrong and you are too for agreeing with him. Sorry, but just biasing a machine for a certain hardware aspect doesn't make it superior. It doesn't hold a candle to so many other features of A8 which NES and other 8-bit consoles lack.


I understand that and YOU can stop being so condescending. The feature line items the A8 had over the NES were basically irrelevant to the hordes playing the SMB series, Kirby series, and other well regarded franchises on the title. My point was the NES was very good at such games and developing them was relatively easy. Can the A8 be cudgeled into doing such a game? Sure, but it isn't easy or quick and the results are debatable. We basically have Crownland and a small handful of other titles to hold up in that regard and the number will stay small because the limited talent and expense pool for creating them probably isn't going care about the no doubt voluminous feature list you'll reply to this with.
...

Are we talking about the same point here-- doesn't look like it. When you compare a computer system with a console, the computer automatically gets a whole bunch of advantages so even with you more tiles or another channel or two of sounds don't hold a candle to what the A8 can do. A8 is well-rounded in terms of its computing capabilities whereas NES and some others like 7800 are stressing just sprites or tiles. NES has very little RAM, no scanline based IRQs, no WSYNC, serialized joystick ports, less colors, very little sprite collision/priority registers, NO KB/Disk drive, etc. etc. Doesn't matter if you can build a few games targetting its strengths that show up a little better.

The NES IS superior for big-world tile based games and those were the "killer apps" for the console. To be sure, the A8 has it all over the NES for Ballblazer but Ballblazer wasn't what was making the NES a hit. The A8 can no doubt show some superiorities in other areas but so what? They aren't terribly relevant to type of gaming that started predominating in the mid eighties.

And while I'm on the point of "quick and easy", the A8 can truly do some astounding things in the hands of a super talented developer even things that aren't easily replicated elsewhere. But to middle of the bell curve devs, the A8 doesn't yield it's treasures easily or quickly and platforms like the NES did.
...

It's the reverse; it's the middle of the bell curve applications/games where A8 wins. See explanation above. A8 shows the major strengths; NES is good just for a few games biased towards its tiles. And that cartridge connector isn't a big thing either. Stressing one aspect of the hardware and then claiming it superior over A8 is the exact faulty logic that I was disputing.


It would seem like that a computer would be better structured then a game console just made for sprite animation... Considering the times, most of the arcades were mostly sprite based machines, not including the vector arcades, thus defined what was needed to make video games during that time. Game systems like the NES were task specific graphics and sound computers to produce a certain product, which were the sprite based video games, that sold very well during that time. But the A8 computers seemed more flexible then an NES because of it's well rounded system design. Keep in mind that video game crash, due to an over satuation of sprite based games, made sprites the norm/industry standard; so for sprite based games the NES served its purpose. But to me it seems like the A8 (as you-all call them) has more flexibility especially when you consider how much more RAM it had over the NES. That alone seems like it would've gave some kind of graphical momentum over the NES even though it couldn't display sprites and tiles as fast as an NES. 64K is a lot of RAM compared to 2K was it the NES sported?


They try to expand the RAM through cartridges which is inefficient/expensive and then you mine as well consider plug-in expansions for Atari computer as well. But the scanline IRQs lacking is a killer as now you can't create incarnations of sprites and reuses of colors and other registers. So Atari 800 although with 4 sprites and 4 missiles can end up with more sprites on screen (depending on application).

A find this all very exciting! Especially as a musician I can see the benefits of a lot of this! I'm very curious about AMY sound chips and new quad POKEYs. Would it be possible to modify the POKEY to get rid of the detuning problem on a hardware level?


The only problem I ever had with POKEY sounds was when I was trying to play-back DAC-based sounds and had disk loading going on in the background.

#158 atariksi OFFLINE  

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Posted Mon May 17, 2010 5:26 AM

It allows other devices to use the bus on otherwise idle cycles without stalling the CPU, which the 6502 doesn't do.

Otherwise, the ST would effectively run at 4 MHz, where in reality it only has 50% of the bus cycles given to it but doesn't suffer anywhere near a 50% throughput penalty.


Not really. If I have Move D0,$4D, it takes 4 cycles for opcode fetch (2 actually use the bus and 2 are internal operations or do nothing), 4 cycles for operand fetch, and 4 cycles for read from location $4D. On 6502, it would be LDA $4D which is 1 cycle for opcode fetch, 1 cycle for operand fetch, and 1 cycle to read from location $4D. So 68000 takes 12 cycles but some external chip like a DMA controller which is synched up with the 68000 can utilize the second of the 2 cycles for each of the 4 cycles for another bus cycle. So even in this case, it's not as effective as 6502 which automatically optimized the bus usage. The 6502 instructions like TAY, TYA, etc. which do not need bus on 2nd cycle can be further optimized by some external chip to use that second cycle for DMA or coprocessing although they didn't put such a chip in on Atari 800. Also, there are exceptions on 68000 where the second 2 cycles aren't available and 68000 has to be halted and delays the instruction execution.


Most assemblers it's Move $4D,D0 instead of Move D0,$4D (intel notation prefers destination first whereas motorola is usually destination 2nd).

#159 frogstar_robot OFFLINE  

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Posted Mon May 17, 2010 6:27 AM

It would seem like that a computer would be better structured then a game console just made for sprite animation... Considering the times, most of the arcades were mostly sprite based machines, not including the vector arcades, thus defined what was needed to make video games during that time. Game systems like the NES were task specific graphics and sound computers to produce a certain product, which were the sprite based video games, that sold very well during that time. But the A8 computers seemed more flexible then an NES because of it's well rounded system design. Keep in mind that video game crash, due to an over satuation of sprite based games, made sprites the norm/industry standard; so for sprite based games the NES served its purpose. But to me it seems like the A8 (as you-all call them) has more flexibility especially when you consider how much more RAM it had over the NES. That alone seems like it would've gave some kind of graphical momentum over the NES even though it couldn't display sprites and tiles as fast as an NES. 64K is a lot of RAM compared to 2K was it the NES sported?


Stuff a resident interpreter and hang a keyboard off a console and you have a "computer". There is no technical reason why the NES chipset couldn't have been made a computer though marketing reasons on the other hand.... It is true the A8 and other home computers of the era have a RAM advantage over the NES but cart based systems could make up for that in their carts. Kirby's Adventure was a 768K cart for instance. Carts could occasionally contain extra RAM, supplemental sound chips, or even rudimentary graphics accelerators. NES carts tended to be physically segmented into code and data portions with minimal work required to decode that data and throw it to the screen.

#160 frogstar_robot OFFLINE  

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Posted Mon May 17, 2010 6:31 AM

A find this all very exciting! Especially as a musician I can see the benefits of a lot of this! I'm very curious about AMY sound chips and new quad POKEYs. Would it be possible to modify the POKEY to get rid of the detuning problem on a hardware level?


Putting four POKEYs in an A8 is somewhat new. Quad POKEYs aren't new at all. A single chip containing four POKEYs used to be a common arcade part. As for the detuning, I've read of experiments with varying the clock rate to the POKEY but have no idea what their success was. A POKEY used in this way would have to be configured strictly as a sound generator. Diddling it's clock would wreak havoc with IO devices hanging off it.

#161 GroovyBee OFFLINE  

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Posted Mon May 17, 2010 6:40 AM

But the scanline IRQs lacking is a killer as now you can't create incarnations of sprites and reuses of colors and other registers. So Atari 800 although with 4 sprites and 4 missiles can end up with more sprites on screen (depending on application).


:roll: You haven't heard about MMC3 the most popular mapper on the NES? Or checking for sprite-0 hits on a standard NES?

#162 atariksi OFFLINE  

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Posted Mon May 17, 2010 12:04 PM

But the scanline IRQs lacking is a killer as now you can't create incarnations of sprites and reuses of colors and other registers. So Atari 800 although with 4 sprites and 4 missiles can end up with more sprites on screen (depending on application).


:roll: You haven't heard about MMC3 the most popular mapper on the NES? Or checking for sprite-0 hits on a standard NES?


Yeah, it's another hardware add-on through the cart. Nothing standard. I have so many hardware added on to my 800XL including a PC laptop so perhaps I should figure that into my Atari 800 spec as well.

Here's the memory map according to their docs:

0000h-07FFh Internal 2K Work RAM (mirrored to 800h-1FFFh)
2000h-2007h Internal PPU Registers (mirrored to 2008h-3FFFh)
4000h-4017h Internal APU Registers
4018h-5FFFh Cartridge Expansion Area almost 8K
6000h-7FFFh Cartridge SRAM Area 8K
8000h-FFFFh Cartridge PRG-ROM Area 32K

So just talk about the standard internal registers not something in the Cartridge expansion area.

As far as sprite hit detection, I don't see any IRQ associated with it; if you have to poll it, that's useless and furthermore the limited collision detection allows only one collision detection per frame as there's no HITCLR like Atari 800. Even PCs have a scanline counter although they don't support vertical splits, but NES doesn't even that.

#163 atariksi OFFLINE  

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Posted Mon May 17, 2010 12:10 PM


It would seem like that a computer would be better structured then a game console just made for sprite animation... Considering the times, most of the arcades were mostly sprite based machines, not including the vector arcades, thus defined what was needed to make video games during that time. Game systems like the NES were task specific graphics and sound computers to produce a certain product, which were the sprite based video games, that sold very well during that time. But the A8 computers seemed more flexible then an NES because of it's well rounded system design. Keep in mind that video game crash, due to an over satuation of sprite based games, made sprites the norm/industry standard; so for sprite based games the NES served its purpose. But to me it seems like the A8 (as you-all call them) has more flexibility especially when you consider how much more RAM it had over the NES. That alone seems like it would've gave some kind of graphical momentum over the NES even though it couldn't display sprites and tiles as fast as an NES. 64K is a lot of RAM compared to 2K was it the NES sported?


Stuff a resident interpreter and hang a keyboard off a console and you have a "computer". There is no technical reason why the NES chipset couldn't have been made a computer though marketing reasons on the other hand.... It is true the A8 and other home computers of the era have a RAM advantage over the NES but cart based systems could make up for that in their carts. Kirby's Adventure was a 768K cart for instance. Carts could occasionally contain extra RAM, supplemental sound chips, or even rudimentary graphics accelerators. NES carts tended to be physically segmented into code and data portions with minimal work required to decode that data and throw it to the screen.


But those carts are not standard hardware so if you did make it into a computer, you would have people writing programs on disks or through the web that you have to execute through standard hardware. And furthermore, you need more than just a keyboard, you need some I/O ports for disk drives or other expansion (as the joystick ports are serial) and a good OS. But then you'll be out of RAM so perhaps you need to define a standard cartridge that everyone MUST have that contains an OS, keyboard drivers, etc. It never happened so no sense in doing hypothetical comparisons.

#164 Havok69 OFFLINE  

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Posted Mon May 17, 2010 1:21 PM

Atari FTW!

#165 Keatah ONLINE  

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Posted Wed Jun 1, 2011 11:10 AM

bump!

#166 fibrewire OFFLINE  

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Posted Wed Jun 1, 2011 11:16 PM

There is no technical reason why the NES chipset couldn't have been made a computer though marketing reasons on the other hand.... It is true the A8 and other home computers of the era have a RAM advantage over the NES but cart based systems could make up for that in their carts.

A good comparison of capability is that NES games can *ALMOST* be played on the Atari 800 - download the ATR...

#167 fibrewire OFFLINE  

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Posted Thu Sep 1, 2016 4:44 PM

Here is KERI !!! This brings us extremely close to being able to do a new 8bit recreation!!!


attachicon.gifkeri.jpg



Curt

Any chance you could post up the GDS files of the chips you found?



#168 mytekcontrols OFFLINE  

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Posted Fri Sep 2, 2016 2:44 AM

Any chance you could post up the GDS files of the chips you found?


I'd be very surprised if Curt replies to your request. He doesn't seem to hang out here anymore that I've seen. But it sure would be cool if he did. Good luck.

- Michael

#169 AtariGeezer ONLINE  

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Posted Fri Sep 2, 2016 3:56 AM

I'd be very surprised if Curt replies to your request. He doesn't seem to hang out here anymore that I've seen. But it sure would be cool if he did. Good luck.

- Michael

He was last online: Aug 29 2016 8:17 PM



#170 mytekcontrols OFFLINE  

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Posted Fri Sep 2, 2016 4:49 AM

He was last online: Aug 29 2016 8:17 PM


Last post was nearly 3 months ago, with another 2 months before that, and that was it for 2016. So basically not very active on AA anymore. Since I first started on AA a little over a year ago, I tried multiple times to get in touch with Curt via PM's and a few email attempts letting him know that I had developed a product that would take advantage of the keyboard port on the 7800XM thinking that would be of interest to him, but never got a response. Can't fault the guy, since I know he's been through a lot. Anyway just saying... that's been my experience, and hopefully others have better luck.

- Michael

EDIT: I met Curt about 15 years ago and found him to be a great guy, and quite the resource for all things Atari. It would be great to have him back as involved as he once was on AA, and I'm sure he is missed by many.

Edited by mytekcontrols, Fri Sep 2, 2016 4:59 AM.


#171 Matej OFFLINE  

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Posted Mon Apr 24, 2017 3:12 AM

Any news on AMY, QUADPOKEY, STEREOPOKEY, KERI, ANTIC-E???



#172 DavidMil OFFLINE  

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Posted Thu Aug 17, 2017 10:43 PM

Anyone heard anything? I have a feeling this is a dead thread...

 

DavidMil



#173 mytekcontrols OFFLINE  

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Posted Thu Aug 17, 2017 11:07 PM

Sadly I think this is no more  :(

 

- Michael



#174 DrVenkman OFFLINE  

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Posted Fri Aug 18, 2017 6:21 AM

Love Curt’s ambitions and ideas but his health problems have derailed most of those, apparently. *sigh*




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