GAMECART, a hidden register in the STE

[czietz]

The excellent "We Love Atari (Volume Two)" also reveals the probable reason for the existence of the GAMECART register. Page 154 has an internal Atari memo for a (never realized) "STE Game Machine" codenamed "Project Robin" that would use the GSTMCU and have 512k of cartridge ROM.

[tyk]

Usually, as you might know, the cartridge port uses addresses $FA0000 - $FBFFFF, where $FAxxxx is decoded to select signal ROM4 and $FBxxxx is decoded to ROM3. With the GAMECART bit set, $D80000 - $DBFFFF will map to ROM4 and $DC0000 - $DFFFFF to ROM3. Access to $FA0000 to $FBFFFF will then cause a bus error. Unfortunately this expanded address range (512 kB instead of 128 kB) cannot be used without HW mod, because only address lines up to A15 are present at the cartridge port, only allowing one to directly address 2*64 kB.

In Atari Compendium:"Newer Arari computers support larger cartridges"...could be there bank switching method like in 8-bit systems like MSX or Nintendo had their 512 KB (4 MBits) cartridges with 16bit addressline in same timeperioid? We might need proto-cartridge to know that bankswithing method. And the newer computers can be TT/Falcon and their 68030 on-chip MMU might help that without bank switching chip in cartridge. With 2 banks even easy method goes with buss error trap jumps to switch bank.

[lostdragon]

The excellent "We Love Atari (Volume Two)" also reveals the probable reason for the existence of the GAMECART register. Page 154 has an internal Atari memo for a (never realized) "STE Game Machine" codenamed "Project Robin" that would use the GSTMCU and have 512k of cartridge ROM.

Please excuse the necrobump, but as someone who's been assisting various sites look into the ST console, aka Project Robin...


Does the memo specifically state STE hardware rather than STFM?

Reason i ask is Curt Vendel had stated...


"Atari was considering an ST based game system as early as 86'" which puts the STE hardware out of the equation.

UK Press claimed Atari were aiming for a middle of 1989 release for it.


I did try reaching out to Rob Zdybel some years ago, had a colleague of his who worked with him at the same time on planned games for it vouch for me, had no reply from Rob about it.

Later discovered Rob had lost everything in a house fire? Plus in an interview with him he seemed to think console wise, Atari went from the 7800 to Jaguar, no mention of XEGS or Lynx..

The colleague couldn't even remember what games they worked on, only that they were original titles, not arcade conversions.

[czietz]

Does the memo specifically state STE hardware rather than STFM?

It does:

robin.jpg

Reason i ask is Curt Vendel had stated...
"Atari was considering an ST based game system as early as 86'" which puts the STE hardware out of the equation.

But that does not exclude that they had a game console idea earlier on, as well. Atari had a lot of ideas that went unrealized.

[tOri]

Hi,

Hat off czietz...

Truly awesome stuff Thanks!

tOri

[lostdragon]

Thanks for sharing, czietz, had a friend of mine send the page scan, just after you kindly shared.


At this stage, it does seem as if the idea of a Games console based on existing ST technology, was considered at various stages of the platforms life cycle.

Ergo, there was no ST Console pitch, but ST Console pitches, each abandoned because it simply wasn't cost effective?

[lostdragon]

Does the memo specifically state STE hardware rather than STFM?

It does:
robin.jpg

Reason i ask is Curt Vendel had stated...
"Atari was considering an ST based game system as early as 86'" which puts the STE hardware out of the equation.

But that does not exclude that they had a game console idea earlier on, as well. Atari had a lot of ideas that went unrealized.

Bob Gleadow Atari UK in a press interview at the time, talked of the ST Console having "An extended graphics capability '.



He ruled out hardware sprites, but talked of" hardware-controlled" horizontal and vertical scrolling... which does tie-in with the STE hardware.



He also claimed 3 ST consoles were already in the hands of (unnamed) US Software houses and UK software houses would get theirs in late December 1988.

[elliot]

"Atari was considering an ST based game system as early as 86'" which puts the STE hardware out of the equation.

Is it possible the the STE was being planned as early 86 or they were still thinking about console versions when it was? If so for this option to creep into the to specification is not unreasonable and then dropped much later when they had the Jag on the horizon.

There are a few extra ground lines on the cartridge port, maybe they planned on using those rather than a larger port, you only need two more lines to access 512k right. I suspect that (seeing as they are ground) using an older FM cart on and STE with those lines enabled as data would have zero effect as long as the register was not enabled. An older 128K ROM would just work but if it was a larger one the first 128K would boot and simply enable the register and then jump to the new range maybe - pure speculation of course there are probably some "gotchas" in this idea.

Are the extra address lines even physically exposed on the MMU (or wherever chip they should be exposed on)? If so could one simply run a 2/3pin cable outside the case and then plug into the side of the Expanded Cart that is plugged into the cart port?

[lostdragon]

I remember a few years ago, when looking into the ST Console and Panther console, on behalf of GTW, i listened to the Antic interview with Rob Zdybel, where Rob made clear he had touched everything Atari had created, seen and unseen.


He was asked about the ST Games console..

But said he could not recall anything about such a console, the JAGUAR was the Games console..






A statement i always found strange as that suggested he was unaware of systems such as the XEGS, Panther and Lynx.

I remember reaching out to Gary Johnson, who worked with Rob on some projects, he couldn't remember much either.


So the research pretty much hit a dead end.


As for the Flame Wars book..


Been having a quick skim through..


This passage caught my eye..



"To be or not to be… Enhanced


In 1989, Atari launched an enhanced version of ST, the STE, with more colours and DMA
sound, but it still could not match the Amiga’s technological lead. In 1990, the Mega STE was
released with Blitter, optional FPU"


Maybe i am reading it completely wrong but, it appears to suggest the Blitter didn't become standard on Atari machines until the 1990 Mega STE.

My memory is awful, but doesn't the time line actually go something like..

1987: The Atari Mega ST 2 ships with a blitter chip.Officially called the "Atari ST Bit-Block Transfer Processor", stylized as BLiTTER.


1989 the 520 and 1040 STE machines arrive, Blitter included on both as standard?

[czietz]

My memory is awful, but doesn't the time line actually go something like..
1987: The Atari Mega ST 2 ships with a blitter chip.Officially called the "Atari ST Bit-Block Transfer Processor", stylized as BLiTTER.
1989 the 520 and 1040 STE machines arrive, Blitter included on both as standard?

Your memory is correct. The Blitter was already standard(*) in the Mega ST (not Mega STE), which was released in 1987. Same goes for the 520/1040STE.

(*) According to https://www.stcarchiv.de/stc1987/09/mega-st some of the very first Mega STs were shipped without Blitter, but just because of poor manufacturing yield.

[Cyprian]

In 1989, Atari launched an enhanced version of ST, the STE, with more colours and DMA
sound, but it still could not match the Amiga’s technological lead.

I guess you mean gaming capabilities because in 1985 in many aspect Atari was head of Amiga, e.g.:
- memory: 4MB vs 256kB (OCS 512kB in 1987, and ECS 2MB in late 1990) ;
- graphics: - high res 31Khz VGA vs poor 15Khz TV (ECS had VGA support in late 1990);
- HDD: fast DMA channel vs never reached (IDE without DMA in 1992);
- HDD: boot from HDD (Amiga had it limited in 1987, full in 1992);
- FDD - true Floppy Disk controller vs faked one (never reached, Amiga had fake two pass controller, second pass by blitter);
- OS: full in ROM vs never reached (Workbech was loaded from FDD);
- OS: multiplatform (Intel/Motorola) vs MorphOS in 2000.

[lostdragon]

My memory is awful, but doesn't the time line actually go something like..
1987: The Atari Mega ST 2 ships with a blitter chip.Officially called the "Atari ST Bit-Block Transfer Processor", stylized as BLiTTER.
1989 the 520 and 1040 STE machines arrive, Blitter included on both as standard?

Your memory is correct. The Blitter was already standard(*) in the Mega ST (not Mega STE), which was released in 1987. Same goes for the 520/1040STE.

(*) According to https://www.stcarchiv.de/stc1987/09/mega-st some of the very first Mega STs were shipped without Blitter, but just because of poor manufacturing yield.

Many thanks, having turned 50,both my memory and eyesight are not anything like they used to be

So, it's a small oversight by the authors.

Maybe something that could be addressed in a revised edition?.

[lostdragon]

In 1989, Atari launched an enhanced version of ST, the STE, with more colours and DMA
sound, but it still could not match the Amiga’s technological lead.

I guess you mean gaming capabilities because in 1985 in many aspect Atari was head of Amiga, e.g.:
- memory: 4MB vs 256kB (OCS 512kB in 1987, and ECS 2MB in late 1990) ;
- graphics: - high res 31Khz VGA vs poor 15Khz TV (ECS had VGA support in late 1990);
- HDD: fast DMA channel vs never reached (IDE without DMA in 1992);
- HDD: boot from HDD (Amiga had it limited in 1987, full in 1992);
- FDD - true Floppy Disk controller vs faked one (never reached, Amiga had fake two pass controller, second pass by blitter);
- OS: full in ROM vs never reached (Workbech was loaded from FDD);
- OS: multiplatform (Intel/Motorola) vs MorphOS in 2000.

That quote is from the book, but yes, I understood it as them referring to the gaming abilities of both platforms.

[12MHz]

Hi Christian,

it would be interesting to know whether one of the operating systems already provides for booting in the new address range. If it were available in the TT, it would be interesting to know whether this is already implemented in TOS 3.06 or possibly in the latest operating system, TOS 4.04?

Best regards
Robert

[LaceySnr]

Minor point reading this, but the STE hardware would make sense given that's where the expanded controller points came into play too

[SyntaxError]

Interesting discovery. But for me, sadly, it is just another proof that something was wrong in Atari in those years....

ia ia... Atulhu f Tagh, after the jag it was clear Ctulhu himself was on the board of directors , i think there's always been something wrong with Atari heheh, all the more interesting

[czietz]

it would be interesting to know whether one of the operating systems already provides for booting in the new address range. If it were available in the TT, it would be interesting to know whether this is already implemented in TOS 3.06 or possibly in the latest operating system, TOS 4.04?

No. No TOS version accesses the GAMECART register, which would be the prerequisite for booting a cartridge from the alternative addresses. In any case and as stated in the original post, the cartridge port is limited by the amount of address lines. Hence, you wouldn't gain anything from switching to the alternative addresses.