Ultimate1MB

[drac030]

Just setup two different playfields (for example a single blank pixel and a set pixel) in standard and extended RAM, then place a player over the pixel and check the collision register.

 

Or setup a DL with DLI in ext RAM, and without in base RAM, switch the CPU to the ext and see if the DLI got triggered.

[HiassofT]

Or setup a DL with DLI in ext RAM, and without in base RAM, switch the CPU to the ext and see if the DLI got triggered.

That's a clever idea, thanks for sharing it!

 

so long,

 

Hias

[flashjazzcat]

The trouble with ANTIC mode per se is that there aren't separate bank registers for ANTIC and CPU. If ANTIC could address one ext bank while the CPU could address a different ext bank, it would be most useful. As it stands - with ANTIC and CPU sharing banking bits - it's not that useful in any app which runs under a DOS.

[HiassofT]

Or setup a DL with DLI in ext RAM, and without in base RAM, switch the CPU to the ext and see if the DLI got triggered.

I just had another idea: setup 2 different DLs and count how many cycles were stolen by Antic.

 

For example: one DL with Antic mode 2, another one with a blank line ($70). Wait for the DL to start, wait some 180-200 cycles and then check if VCOUNT has changed.

 

so long,

 

Hias

[HiassofT]

The trouble with ANTIC mode per se is that there aren't separate bank registers for ANTIC and CPU. If ANTIC could address one ext bank while the CPU could address a different ext bank, it would be most useful. As it stands - with ANTIC and CPU sharing banking bits - it's not that useful in any app which runs under a DOS.

I totally agree, IMHO the XE separate ANTIC mode is pretty much useless.

 

<mode=dreaming>

A separate bank register for ANTIC would be really nice, and it would be even better if we could also use different banks for CPU reads and CPU writes. This would make copying/moving data from one bank to another a lot easier.

 

But, I know, such a banking scheme doesn't fit into PORTB anymore and would require more/other memory locations and, of course, new software.

</mode>

 

so long,

 

Hias

[STeSearcher]

What kind of custom chips?

 

Such as a GAL which has to be programmed. Many mods for the Atari (ST's too) use custom programmed chips.

[+rdemming]

What kind of custom chips?

 

Such as a GAL which has to be programmed. Many mods for the Atari (ST's too) use custom programmed chips.

 

In the 80's the term "custom chips" refered to chips that were custom designed/made for some company/device. Like the Atari 8-bit ANTIC, ST shifter, Amiga Paula etc. Non custom chips were of the shelf chips like 68000, ST MPF, ST YM soundchip.

 

I would call GAL/PAL/CPLD/FGPA/etc. just programmable logic chips instead of custom chips.

 

And yes, this extension contains a programmable CPLD chip. Using discrete logic chips (74xx chips), these kinds of extensions would be too big because of the high chip count then.

 

Robert

Edited April 28, 2010 by rdemming

[STeSearcher]

/snip

I would call GAL/PAL/CPLD/FGPA/etc. just programmable logic chips instead of custom chips.

 

And yes, this extension contains a programmable CPLD chip. Using discrete logic chips (74xx chips), these kinds of extensions would be too big because of the high chip count then.

 

Robert

 

Ah, ok...thanks!

[griz]

I'm going to need at *least* two of those!

 

Me too! Thanks for doing this Candle.

 

that one goes into Your 600xl

 

Will it fit inside a 600XL? Will the 600XL require the 64K upgrade first?

[flashjazzcat]

Will it fit inside a 600XL? Will the 600XL require the 64K upgrade first?

Apparently it'll fit in a 600XL. The computer will certainly require a (simple, ten minute) 64K upgrade first.

[candle]

"whatever flashjazzcat and rdemming says"

[drac030]

I just had another idea: setup 2 different DLs and count how many cycles were stolen by Antic.

 

For example: one DL with Antic mode 2, another one with a blank line ($70). Wait for the DL to start, wait some 180-200 cycles and then check if VCOUNT has changed.

 

That will probably work, but it has the disadvantage of being dependent on the CPU speed. If the machine is (by chance) accelerated, the test will fail. I liked your previous idea (with collisions) better

 

I agree that the CPU/ANTIC separate ext RAM addressing has limited use, but it anyways gives a tiny bit more possibilities than an expansion without that feature, so I'd personally like 320k CompyShop (with separate ANTIC/CPU access) better than a 1 MB without.

[+JAC!]

Not at all :-)

Just setup two different playfields (for example a single blank pixel and a set pixel) in standard and extended RAM, then place a player over the pixel and check the collision register.

 

so long, Hias

 

Hehe- Hias I love this one. Reminds me of that copy protection that I once saw on C64. It used a 1 hires pixel sprite and collision detection to determine the 8 bits in a write-only register of the 6510 which could not be read using LDA.

 

BTW: I would buy one of these!

[Shawn Jefferson]

I totally agree, IMHO the XE separate ANTIC mode is pretty much useless.

 

It's not all that useful, and probably not worth making any software specifically for since there are so many upgrades out there that don't support it.

 

However, by moving the screen and display lists into a seperate bank it gives you more flexibility on memory placement with your programs, and saving even a little of the 64k is probably worth it. Any CPU access to extended memory could/would have to happen during the VBI I guess.

 

As it is, I'm not that happy with the way that Atari decided to make the memory banking area 16k, right in the "middle" of the memory map-just that fact cuts down the utility of it quite a bit, IMO.

[Rybags]

IMO it is useful just for the fact that you can exclude CPU or Antic from the switching.

 

Leaves you free to put screen data in the standard area, then the CPU can wander off and do whatever it wants in the extended area.

Or on the other hand, tuck the screen away in extended and leave the full 62K main area free for program and data.

[+Philsan]

Sebastian, I am unable to solder but I don't like external wires connected to joystick ports and I love old computers aesthetics...

I have a completely socketed 800XL, so if only two wires must be soldered... one expansion for me, please!

[candle]

yes, it would require only two wires in that case - one for PHI2 signal, the other for R/W signal - both are not present on MMU nor on system ROM chip, thus have to be sourced from somewhere else

Edited April 30, 2010 by candle

[+Philsan]

it contains 512k flash chip that stores SpartaDos X (448kB for SDX) and up to 4 system roms

I have always used "standard" hardware and "traditional" DOS 2.5 so I have two simple questions.

Nowadays what is the importance of having 4 system roms?

Differences between SpartaDos X and RealDos?

[+bob1200xl]

What you need is a 65816 with an ANTIC banking register added. Moving data between banks or main memory is as simple as: LDA $aabbcc,Y STA $ddeeff,Y and ANTIC has his own 64K bank - the whole thing...

 

This would all work with an unmodified XL OS and in 8-bit 6502 emulation mode in the 65816. Might be worth some new s/w.

 

 

Bob

 

 

 

 

The trouble with ANTIC mode per se is that there aren't separate bank registers for ANTIC and CPU. If ANTIC could address one ext bank while the CPU could address a different ext bank, it would be most useful. As it stands - with ANTIC and CPU sharing banking bits - it's not that useful in any app which runs under a DOS.

I totally agree, IMHO the XE separate ANTIC mode is pretty much useless.

 

<mode=dreaming>

A separate bank register for ANTIC would be really nice, and it would be even better if we could also use different banks for CPU reads and CPU writes. This would make copying/moving data from one bank to another a lot easier.

 

But, I know, such a banking scheme doesn't fit into PORTB anymore and would require more/other memory locations and, of course, new software.

</mode>

 

so long,

 

Hias

[atariksi]

What you need is a 65816 with an ANTIC banking register added. Moving data between banks or main memory is as simple as: LDA $aabbcc,Y STA $ddeeff,Y and ANTIC has his own 64K bank - the whole thing...

 

This would all work with an unmodified XL OS and in 8-bit 6502 emulation mode in the 65816. Might be worth some new s/w.

 

 

Bob

 

Yeah, I would be interested in a plug-in board if I can use a 65816 even at same speed at 1.79Mhz. No soldering.

[atariksi]

yes, it would require only two wires in that case - one for PHI2 signal, the other for R/W signal - both are not present on MMU nor on system ROM chip, thus have to be sourced from somewhere else

 

That would mean 4 places to solder or are you going to attach the two wires on the board already so we just solder to the PHI2 and R/W lines on MB?

[HiassofT]

Hi Bob!

 

What you need is a 65816 with an ANTIC banking register added. Moving data between banks or main memory is as simple as: LDA $aabbcc,Y STA $ddeeff,Y and ANTIC has his own 64K bank - the whole thing...

 

This would all work with an unmodified XL OS and in 8-bit 6502 emulation mode in the 65816. Might be worth some new s/w.

Thanks for the info, this sounds really interesting! I haven't had my hands on a 65816 yet, but this feature sounds really cool. I guess I'll have to download a datasheet and start reading :-)

 

so long,

 

Hias

[atariksi]

yes, it would require only two wires in that case - one for PHI2 signal, the other for R/W signal - both are not present on MMU nor on system ROM chip, thus have to be sourced from somewhere else

 

That would mean 4 places to solder or are you going to attach the two wires on the board already so we just solder to the PHI2 and R/W lines on MB?

 

So if you put a two-pin header on the 1MB board and same on a 65816 PCB, then you could just put a two pin wire from one board to the other and avoid all soldering. For those that don't take the 65816 PCB, they just solder or squeeze in the two wires on the PHI2 and R/W on the processor (6502C).

[candle]

i find connectors verry usefull things

probably the most important invetion of mankind

that is - just afeter a DOS

[atariksi]

i find connectors verry usefull things

probably the most important invetion of mankind

that is - just afeter a DOS

 

I would say electricity would be a more important invention. Connectors without soldering are better than with soldering. Not only does it help you sell more to nontechnical people but it also allows you to easily reverse things in case your machine fails and you want to transplant the device into another machine. I'm sure many people have extra Ataris in case one fails.

 

DOS is a very good product but being forced to use it is not a good thing. The more choices you have the more creative you can be.