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bob1200xl

7.16mhz 1200XL

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So, this is the accelerator.

 

Pull the CPU and old RAM, add 5 wires to the bottom of the board, plug in the new board. All CPU access to RAM is now at 7.16mhz. All other system activity is at 1.79 mhz. The new board has a 14mhz oscillator, a high-speed SRAM, a 65816, and an ATMEL CPLD (ATF750C).

 

Most everything works pretty well. Many games and such look and play the same - they are ROMs and do not move the OS into RAM. Some m/l, bit-banging code has problems - SAM sounds like a chipmunk, for example. If you run the OS from RAM, everything gets faster, of course. TBXL screams...

 

Anticipating questions:

 

U-Build-It ===> $50?

 

64K.

 

600XL, 800XL, 1200XL (with the XL OS mod)

 

Always ON.

 

Don't know - have not tried it...

 

 

Bob

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Looks really good, Bob.

 

In fact, I think the simplicity of the design could make it become Hugely popular..

 

You gonna publish schematics/parts/instructions/CPLD code?

 

Or at least make them and sell them?

 

Ive alwayse admired the straightforward, well-thought-out, and (not overcomplicated) nature of your upgrade projects.

 

I think this has the potential to become the new standard for acceleration on the ATARI 8-bit scene.

 

Just look what MyIDE has done in less than 5 years..

 

Anywayze.. awesome upgrade, man..

Edited by MEtalGuy66

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post-14708-1220486813_thumb.jpg

 

So, this is the accelerator.

 

Pull the CPU and old RAM, add 5 wires to the bottom of the board, plug in the new board. All CPU access to RAM is now at 7.16mhz. All other system activity is at 1.79 mhz. The new board has a 14mhz oscillator, a high-speed SRAM, a 65816, and an ATMEL CPLD (ATF750C).

 

Most everything works pretty well. Many games and such look and play the same - they are ROMs and do not move the OS into RAM. Some m/l, bit-banging code has problems - SAM sounds like a chipmunk, for example. If you run the OS from RAM, everything gets faster, of course. TBXL screams...

 

Anticipating questions:

 

U-Build-It ===> $50?

 

64K.

 

600XL, 800XL, 1200XL (with the XL OS mod)

 

Always ON.

 

Don't know - have not tried it...

 

 

Bob

I would buy a kit at that price

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U-Build-It ===> $50?

 

I'd make a run of these if the plans and such were available.

 

Steve

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I'd buy one too!

 

Would it be possible to vary the speed? I can imagine situations where 200% or even 125% of original speed would be desirable...

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Jacobus:

 

As the crystal is a fixed frequency you won't be able to vary it (at least, not easily).

 

I'm more interested in the empty sockets - I presume they're for additional RAM? What's the max per socket?

 

And have you tried softloading Drac030's '816 ROM? Does it speed things up?

 

 

Yummy, yummy, yummy... Steve - put me down for (at least) one...

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At $50, I'd probably go for 2.

 

Very nice upgrade - something you can get immediate benefit from. And, opens up enormous gaming possibilities.

 

So, have you run stuff like Fractalus on it?

 

ed - also, do you think it will translate well to PAL? Guessing here that you'd probably need a slightly slower master clock.

Edited by Rybags

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Cool. So I assume all the RAM lives on the board then? Does your clock generator replace the system one - and if not, how do you sync your clock with the system clock? How does ANTIC deal with the board - you just halt the '816 for 4 cycles at a time rather than 1? Do you support 130XE banked RAM modes, and if so, do you match up the banked RAM with '816 extended RAM? How do you implement /HALT - are you using /BE + locking the clock input high?

 

Good work - simple yet awesome!

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I'm not inclined to make or sell them if another viable channel is available. (in other words, someone else is doing them well) I might be available to program the CPLD (takes 15 seconds...) and the PAL for people. The rest is just hardware.

 

I'll wait until the ABBUC contest is over before I document it. (CUPL and PCB layout)

 

Looks really good, Bob.

 

In fact, I think the simplicity of the design could make it become Hugely popular..

 

You gonna publish schematics/parts/instructions/CPLD code?

 

Or at least make them and sell them?

 

Ive alwayse admired the straightforward, well-thought-out, and (not overcomplicated) nature of your upgrade projects.

 

I think this has the potential to become the new standard for acceleration on the ATARI 8-bit scene.

 

Just look what MyIDE has done in less than 5 years..

 

Anywayze.. awesome upgrade, man..

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There is no such provision for doing that - it would mean re-programming the CPLD. You'd be on your own there...

 

Bob

 

 

I'd buy one too!

 

Would it be possible to vary the speed? I can imagine situations where 200% or even 125% of original speed would be desirable...

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Sounds interesting. Speaking of MyIDE though... would this upgrade work with a MyIDE cart or internal upgrade? The MyIDE cart loads it's own OS into RAM, so your upgrade should speed up hard drive access times with MyIDE ? Cartridge access is still at 1.79Mhz?

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The empty sockets were in anticipation of complex logic requirements that didn't materialize. Not for RAM...

 

No, I have not tried the '816 OS.

 

Bob

 

 

 

Jacobus:

 

As the crystal is a fixed frequency you won't be able to vary it (at least, not easily).

 

I'm more interested in the empty sockets - I presume they're for additional RAM? What's the max per socket?

 

And have you tried softloading Drac030's '816 ROM? Does it speed things up?

 

 

Yummy, yummy, yummy... Steve - put me down for (at least) one...

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Have not tried Fractalus...

 

I don't know enough about PAL to answer that. I imagine there are a couple of hardware types over there that can make PAL work.

 

Bob

 

 

 

At $50, I'd probably go for 2.

 

Very nice upgrade - something you can get immediate benefit from. And, opens up enormous gaming possibilities.

 

So, have you run stuff like Fractalus on it?

 

ed - also, do you think it will translate well to PAL? Guessing here that you'd probably need a slightly slower master clock.

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All your RAM is on the board. The clock generator replaces the system clock. You not only have to stop the CPU for the four cycles that ANTIC is on the buss, you have to align with the master clock as well. This means that the minimum HALT duration is 4 cycles - could be a high as 7! No banked RAM support - 64K only. HALT asserts BE, yes.

 

Bob

 

 

Cool. So I assume all the RAM lives on the board then? Does your clock generator replace the system one - and if not, how do you sync your clock with the system clock? How does ANTIC deal with the board - you just halt the '816 for 4 cycles at a time rather than 1? Do you support 130XE banked RAM modes, and if so, do you match up the banked RAM with '816 extended RAM? How do you implement /HALT - are you using /BE + locking the clock input high?

 

Good work - simple yet awesome!

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I do not have a MyIDE. I have considered the newer, high-speed CF cards, however. They can probably run at 7mhz.

 

The FRAM memory in the video cartridge should, also.

 

Cartridge is accessed at 1.79 mhz.

 

Bob

 

 

Sounds interesting. Speaking of MyIDE though... would this upgrade work with a MyIDE cart or internal upgrade? The MyIDE cart loads it's own OS into RAM, so your upgrade should speed up hard drive access times with MyIDE ? Cartridge access is still at 1.79Mhz?

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post-14708-1220486813_thumb.jpg

 

So, this is the accelerator.

 

Pull the CPU and old RAM, add 5 wires to the bottom of the board, plug in the new board. All CPU access to RAM is now at 7.16mhz. All other system activity is at 1.79 mhz. The new board has a 14mhz oscillator, a high-speed SRAM, a 65816, and an ATMEL CPLD (ATF750C).

 

Most everything works pretty well. Many games and such look and play the same - they are ROMs and do not move the OS into RAM. Some m/l, bit-banging code has problems - SAM sounds like a chipmunk, for example. If you run the OS from RAM, everything gets faster, of course. TBXL screams...

 

Anticipating questions:

 

U-Build-It ===> $50?

 

64K.

 

600XL, 800XL, 1200XL (with the XL OS mod)

 

Always ON.

 

Don't know - have not tried it...

 

 

Bob

 

Very nice. I would like at least one. But have a couple questions concerning compatibility:

- Is it compatible with the 800XLF (equipped with Freddie)?

- Is it (or can it be make) compatible with AtariMax's 32in1 OS upgrade?

- Is it (or can it be make) compatible with the 512Kb memory upgrade by Wolfram Fischer?

 

Thanks,

Jozsi

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And have you tried softloading Drac030's '816 ROM? Does it speed things up?

 

It is not intended to speed things up. It just allows new programs to fully utilize the 65C816 potential (i.e. the "native", 16-bit mode).

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Don't know about the XLF. The 'hooks' into the hardware are minimal - it's mostly a matter of physical layout.

 

I think the 32in1 is just a physical issue, also.

 

RAM has been moved to the new board - you can't use the old memory at all.

 

 

Bob

 

 

 

 

 

 

Very nice. I would like at least one. But have a couple questions concerning compatibility:

- Is it compatible with the 800XLF (equipped with Freddie)?

- Is it (or can it be make) compatible with AtariMax's 32in1 OS upgrade?

- Is it (or can it be make) compatible with the 512Kb memory upgrade by Wolfram Fischer?

 

Thanks,

Jozsi

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Don't know about the XLF. The 'hooks' into the hardware are minimal - it's mostly a matter of physical layout.

 

I think the 32in1 is just a physical issue, also.

 

RAM has been moved to the new board - you can't use the old memory at all.

 

Bob

 

Would you please tell me the "hook" points? I'll try to check them on my MB. Should anything need to be desoldered on the motherboard?

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What does it do? Or, how does it do it?

 

What it does is run code in RAM much faster than a stock Atari. You don't have to change the program at all, you just need to execute it from RAM. David Ahl's Benchmark runs in 15 seconds under TBXL, for example. It does not speed up SIO transfers because they are done in hardware. It generally doesn't affect the audio because that is also hardware. Keyboard delay and repeat are normal. For things like BASIC, it is generally enough to just move the OS into RAM. This allows the FP code and the drawing routines to run at 7.16mhz. Graphics that took 1 minute to draw will now take 20 seconds.

 

How does it work? The circuit looks at the output from the Atari PAL at the start of every cycle. (this is the chip that selects the OS, cart, RAM, or I/O that we will access) If we are going to RAM from the CPU, the 7.16mhz clock is selected. Anything else slects the 1.79mhz clock.

 

Does that answer your question?

 

Bob

 

 

 

In layman's terms, what does it do?

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In layman's terms, what does it do?

 

Ditto. What could it do for my RAMBO 256K 1200xl? I suspect that if I have to ask this question, I probably don't need it, but it sounds cool anyway.

 

Edit: ignore the above, Bob1200xl posted before I finished typing.

Edited by yorgle

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Memory has to be removed. The PAL has to be replaced. (CO61618) The CPU has to be socketed - that's where the new board plugs in. You need to disable the old clock and connect the clock from the new board. This is probably the main problem with the Freddie chip machines. I supply a 3.58mhz clock and the Freddie hardware needs 14mhz.

 

I really have not looked at it closely... I would suggest that anyone who wants to run fast just pick up an XL machine and modify that.

 

Bob

 

 

 

Don't know about the XLF. The 'hooks' into the hardware are minimal - it's mostly a matter of physical layout.

 

I think the 32in1 is just a physical issue, also.

 

RAM has been moved to the new board - you can't use the old memory at all.

 

Bob

 

Would you please tell me the "hook" points? I'll try to check them on my MB. Should anything need to be desoldered on the motherboard?

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That's awesome. I would buy one too. The acceleration might help the 8-bit ethernet project. This could make text web browsing or e-mail work efficiently on a stand alone Atari.

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This is probably the main problem with the Freddie chip machines. I supply a 3.58mhz clock and the Freddie hardware needs 14mhz.

 

I really have not looked at it closely... I would suggest that anyone who wants to run fast just pick up an XL machine and modify that.

 

Bob

 

A 65816 can address 16 megabytes without bank switching if you want a machine with more memory. Only issue is the software that requires Freddie style bank switching. You probably have to do some fancy wiring to make your machine backward compatible with software that uses 130XE bankswitching. Not a whole lot of software was released, some people probably just won't even bother with a Freddie.

 

Maybe if 65816 became more of a widespread thing, some may write some games to take advantage of a faster machine. Using Native 65816 code, a game can manipulate many more onscreen objects at once. Can write more elaborate DLIs and a more versatile player/missile 'multiplexer'.

Edited by peteym5

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