Atari 800 right Slot

[jmmhooper]

This might be common knowledge but I wanted to ask. I read in an FAQ that there were only a few cartridges designed for this right slot in the 800? So it is basically a useless slot?

[fibrewire]

Well, you could use it to hold your "Cart Wallet" a cart that has been converted into a wallet

[Bryan]

Yeah, it's of no use to the average user. I guess Atari originally envisioned a more complex scheme where different programs and utilities could be combined. Having one cartridge and a disk drive is much more flexible.

[labrat]

Stash cart! I like it.

 

Well, you could use it to hold your "Cart Wallet" a cart that has been converted into a wallet

[kurtm]

Yeah, it's of no use to the average user. I guess Atari originally envisioned a more complex scheme where different programs and utilities could be combined. Having one cartridge and a disk drive is much more flexible.

 

The disk drive is more flexible, yes. But at the time when the 800 first came out, the disk drives were damned expensive. On top of the 800 being quite expensive. Cartridges a lot less so. The biggest problem was the 400 only had the one slot, so few wanted to make a product that only worked with the less common, high-end machine.

 

--Kurt

[jmmhooper]

Thanks for the feedback. I guess those carts that work in the right slot are real rare hard to find now?

[doctorclu]

Thanks for the feedback. I guess those carts that work in the right slot are real rare hard to find now?

 

Let's see, I have the Monkey Wrench which adds more functions to basic. That was used in the right hand slot.

I also have Magic dump, which screen dumps what is on the screen. I am curious to try that one out actually.

 

A lot more recently Mr Atari played with the MyIde cartridge to where you could load a drive and work with the right hand slot. I am kinda tempted to play with that now too.

[Atari8bitCarts]

Does anyone have Gemini's Magic Dumps instructions book? How do you use them (1 and 2).

[FifthPlayer]

I'm pretty sure the right cartridge slot was discussed in the Joe Decuir interview with ANTIC. If I remember correctly, he said they envisioned a scenario with a "master cartridge" going into the left slot, then content cartridges plugging into the right slot. For instance, an educational system (Left Slot) with the lesson packs as Right Slot cartridges.

 

Of course, the 400/800 hadn't been released yet, so they had no idea if the cart slots would actually be used in that fashion.

[ryanmercer]

I'm pretty sure the right cartridge slot was discussed in the Joe Decuir interview with ANTIC. If I remember correctly, he said they envisioned a scenario with a "master cartridge" going into the left slot, then content cartridges plugging into the right slot. For instance, an educational system (Left Slot) with the lesson packs as Right Slot cartridges.

 

 

 

That's pretty much what I remember too, although not sure if that's the correct guy or podcast but I remember hearing it on one of them int he past year or so.

[AE.drums]

I had a 80 column display expansion board made by "Austin Franklin"; this device used one of the memory slots AND the right cartridge slot to work. I believe the 80 column expansion board was contained in the memory slot and the firmware drivers where contained in the cartridge. I discovered a lot of programs would not run unless I removed the controlling right cartridge. This is the ONLY released device I know of that did in fact make use of the right cartridge slot.

[DavidMil]

I still have my bright orange Thompson Electronics 'ProBurner'. A right hand cartridge that could burn eproms up to 27128 (16K x 8. This cartridge allowed

you to look at ROM carts in the left socket and burn duplicate eproms. It also has a machine language monitor. I remember that I used it to modify my

Eastern Front game. I loaded the game from the cartridge and then I gave all the Luftwaffe 255 starting points. Then I wrote the game to a diskette and

played it from the disk.

 

David Milsop

Kingwood, Texas

Edited January 16, 2017 by DavidMil

[+JAC!]

In the OS docs and the Profibuch I can only see that the OS detects cartridges that end/mirror up to $BFFA-$BFFF.
As a consequence I'd expect that if you only plugin a right slot 4k/8k cart, it cannot have and auto-start code.
The system would boot as normal/start BASIC and then you can access rhe right cart directly at $8000-$9FFF.

 

Is that correct?

 

- Peter/JAC!

[ClausB]

No, the 800 OS will initialize and run a right cart at $9FFA too.

[luckybuck]

Sorry JAC!, but Claus must be right, due to:

 

Monkey Wrench, The (1981)(Eastern House Software)(US)

 

If you were right, then there is no way to tell Atari BASIC about the additional functions Eastern House has provided for the user...

 

Right cart must be max from $8000 to $9FFF as far as I know.

Monkey Wrench, The (1981)(Eastern House Software)(US)!.car.txt

Monkey Wrench II, The (1985)(Eastern House Software)(US)!.car.txt

[JR>]

Anybody ever tried putting these on a maxflash cart and using it in the right slot?

[luckybuck]

:-)

 

First, we should sum up all right carts to be used for that porpose...

-> FAQ

-> back here

-> maybe adapting code?

Edited May 31, 2018 by luckybuck

[Faicuai]

 

Anybody ever tried putting these on a maxflash cart and using it in the right slot?

 

 

Funny that I have owned a MaxFlash for quite a while, and never thought of such basic idea (!!!)

 

But I guess we will need to first, understand the internal connection / "wiring" of the right-slot, how the O/S detects it, and hot it overall handles it, with respect to the left-cart (and what needs to be either wired or SW-provisioned on the right cart for it to work as intended...) For example, if we boot the 800 with Incognito and XL/XE rom, what would happen with the right-cart "presence" if we hold Option-key during boot?

 

And this may also takes us to the next question:

 

Could The!Cart be plugged and booted from the Right-slot, too? that would allow us to program it with (all?) the available right-cart images we can find...

 

The right-slot seems to me an ideal place for things like math co-processors, O/S handlers that could be handled on an ON/OFF basis (or "transactional" in nature, and in terms of information actually exchanged with the host-machine), add-on WiFi Bluetooth connectivity, etc. (although there is a price to pay for allowing the right cart to chew-up another window of linear / RAM space, though).

 

The kind of (of modular) system you could potentially build AND house in the 800 is (I could say) beyond any other model of Atari's entire 8-bit lineup... :-)

[+JAC!]

Wha tI found so far:

 

Monkey Wrench does not autostart but needs to be initialized by the user using X=USR(....) etc.

http://atariage.com/forums/topic/125889-monkey-wrench/page-2?do=findComment&comment=3913997

 

>Could The!Cart be plugged and booted from the Right-slot, too?
It does offer emulation for Right-Slot 8k when plugged into an (left/only) slot of an XL/XE.
Not sure what happens in the right slot... but please don't try it for now :-)

 

From the original OS A/OS B listing, the only reference to $9FFx is in comment, not in the code.

;
;
; THE FOLLOWING EQUATES ARE IN THE CARTRIDGE ADDRESS SPACE.
;
;
; "B" CARTRIDGE ADDR'S ARE 8000-9FFF (36K CONFIG. ONLY)
; "A" CART. ADDR'S ARE A000-BFFF (36K CONFIG. ONLY)
;
; "A" CART. ADDR'S ARE B000-BFFF (48K CONFIG. ONLY)
;
*=$BFFA
CARTCS: .RES 2 ;CARTRIDGE COLD START ADDRESS.
CART: .RES 1 ;CARTRIDGE AVAILABLE FLAG BYTE.
CARTFG: .RES 1 ;CARTRIDGE FLAG BYTE. BIT 0=FLAG1,
CARTAD: .RES 2 ;2-BYTE CARTRIDGE START VECTOR

[+tf_hh]

Wha tI found so far:

 

Monkey Wrench does not autostart but needs to be initialized by the user using X=USR(....) etc.

http://atariage.com/forums/topic/125889-monkey-wrench/page-2?do=findComment&comment=3913997

 

>Could The!Cart be plugged and booted from the Right-slot, too?

It does offer emulation for Right-Slot 8k when plugged into an (left/only) slot of an XL/XE.

Not sure what happens in the right slot... but please don't try it for now :-)

 

IMHO the right cart is only initialised when there´s no left cart plugged in or the left cart is not flagged as runnable:

 

 

When the left cart ("A") is started, a JMP is used - so there´s a never-come-back to the point where cart "B" (the right one) will be executed...

[+JAC!]

I was looking for the wrong thing ($9FFF instead of -$2000) in the OS. I checked in the OS sources from kr0tki and yes, this code is there in the original OS A/OS B. It is no longer there in the later versions of the hardware there was no right slot anymore. So my "problem" is that I am testing the "Right Slot" with The!Cart on an XL. There is correctly boots to BASIC, while on an Atari 800 is starts as expected. At least in Altirra (have no 800 here).

 

 

Regarding: "so there´s a never-come-back to the point" to cart "B"
I tried with MonkeyWrench+BASIC. They are not using the CARTCS but the CARTAD vector of the cartridge. And that is called via JSR. So after the initialization of the right cart there simply is an RTS, the left cart is also called.

 

[Rybags]

A 16K left cart can actually be detected and run as a right cart, even on the 400 (given the OSes are exactly the same).

 

What prevents that is that you need "magic" numbers - it's usually sufficient to just have a nonzero value in $9FFC to prevent accidental attempt at running the phantom right cart.

Unlike left cart, there's no diag mode capability for the right slot.

If a right cart is present (ie proper flags set also), bit 0 of $9FFD has to = 1 to allow a disk boot to be attempted.

 

The Init processing for cartridges is such that the right cart is processed first. As such that would allow for successful implanting of alternate device handlers or even a cart based Dos, and adjustment of memory pointers as needed before a language processor gets control.

 

Cart pinouts - mostly the same except that right cart only gets one sense and one select line - so left cart can map 16K but right cart only 8K.

[Faicuai]

 

IMHO the right cart is only initialised when there´s no left cart plugged in or the left cart is not flagged as runnable:

 

Unbenannt.png

 

When the left cart ("A") is started, a JMP is used - so there´s a never-come-back to the point where cart "B" (the right one) will be executed...

 

VERY interesting...

 

If there is effectively "point of no return" to RIGHT-Cart, upon LEFT-Cart initialization, that suggests the idea of having the LEFT-Cart "bootstrapping" the RIGHT one, at some point in time, or simply by external command AFTER LEFT-Cart booting completes... This is where we can draw some conclusions of how a [ LEFT-Cart + RIGHT-Cart ] scheme operation may have been envisioned by system designers (probably).

 

But that takes us then to ANOTHER issue....

[Faicuai]

I was looking for the wrong thing ($9FFF instead of -$2000) in the OS. I checked in the OS sources from kr0tki and yes, this code is there in the original OS A/OS B. It is no longer there in the later versions of the hardware there was no right slot anymore. So my "problem" is that I am testing the "Right Slot" with The!Cart on an XL. There is correctly boots to BASIC, while on an Atari 800 is starts as expected. At least in Altirra (have no 800 here).

 

RightSlot.png

 

Regarding: "so there´s a never-come-back to the point" to cart "B"

I tried with MonkeyWrench+BASIC. They are not using the CARTCS but the CARTAD vector of the cartridge. And that is called via JSR. So after the initialization of the right cart there simply is an RTS, the left cart is also called.

 

Both.png

 

Well, the bottom-line is:

 

1. There IS "bootstrapping" code for RIGHT-Cart on OS/a/b but THERE IS NONE in XL/XE...
2. The above means that there is NO RIGHT-Cart control in such OS.

 

And if we would ever consider enhancing the current-state of affairs, to bring BACK RIGHT-Cart to XL / XE series (for complete cross-platform equivalence), then:

 

1. I wonder if by means of (say) excellent Sys-Check, our XLs could run with TWO carts. attached at the same time (LEFT on central port, and RIGHT on Sys-Check port)
2. In the above case (XL/XE or especially Atari 800 / Incognito running XL/XE OS), some form of extra code is needed to recognize and handle a physically-present RIGHT-cart.
3. The question then is where to add such code... FJC's wonderful BIOS? or just on The! Cart, so we have a "luxury" (x2) The!Cart setup on the A800? Left one for most of what we know, and right one for all right-cart stuff available plus any other appropriate use in the future....

[Rybags]

I've not used Monkey Wrench but assumed it just used a "wedge" which on Atari is usually implemented by redefining the E: HATABS entry and just intercepting entered text.

If that is the case then it's sort of strange that it'd need a USR command from Basic to get it going. No reason why it couldn't during it's Init setup the required intercepts and it could even detect Basic by doing a checksum - though of course that could easily break due to Rev A-C differences.