Jump to content
IGNORED

XL/XE compatible Atari 800?


Tempest

Recommended Posts

Cool, a Plug'N Pray board would be awesome indeed! That way it can easily be reverted to a stock 800 correct?

 

Well, I have to get some additional signals off the motherboard into the card bay, but there is no cutting of the motherboard. Stock boards can be replaced to revert back to 800 mode. If you do a forum search on the other thread I have on this you can see where I snaked the additional wires into the card bay through the plastic tabs in the back.

 

I was thinking of making a video showing my 800 working in stock 48K mode, pulling the stock boards out and replacing them with the "proof-of-concept" prototypes, to show it working as a 320K/576K 130XE. This way, folks can see how it really works.

Link to comment
Share on other sites

  • 3 months later...
Any news on this? My Atari 800xl is looking quite sad these days and I'd like to get my 800 back out...

 

Tempest

 

Some.. I outgrew the original CPLD and had to move to a device with more I/Os (currently using 49), not to mention it's been through a few re-designs. I'm running simulations to figure out some VHDL bugs before I commit to silicon on the real thing. I can confirm the final design will be a single board that replaces all the memory boards and plugs into the OS personality slot. Going to need about 20 connections to the motherboard, but no cutting required.

 

Currently implemented features (or at least they are in the simulator ;) ):

 

Four extended memory mappers (selected by jumpers):

- 100% compatible 130XE mode with full ANTIC enhance, switchable built-in BASIC, Selftest, OS (needs only single 128K static ram)

- 320K Scott Peterson mode, no ANTIC enhance (needs both 128K and 512K static rams)

- 576K Scott Peterson mode, no ANTIC enhance, no switchable BASIC (needs both 128K and 512K static rams)

- 576K Mathy-style mode, ANTIC enhanced, switchable built-in BASIC, Selftest, OS (needs both 128K and 512K static rams)

 

Theoretically the missing PBI signals have been implemented, but have not been tested yet.

 

Not much free time due to job demands, but still progressing.

 

On a side note, having a purely static design has some interesting possibilities. For example, implementing a simple transparent DMA that runs during ANTIC refresh cycles since you can't disable them and don't need them...

Link to comment
Share on other sites

  • 3 weeks later...

For those interested in this, I have an update!

 

The OS board went through a several redesigns from the original proof-of-concept if you look at the previous threads. I outgrew the original CPLD I planned to do it on (thus the empty socket) and moved on to a larger device because I ran out of I/O pins. Lots of ribbon cable for all those signals. Haven't put jumper blocks on the board so those two blue wires is what I use to select the different memory modes. So this is now a working single-board 800 personality module prototype that provides full XL/XE compatibility (you lose ports 3/4), and you can still switch back to stock by swapping boards.

 

So here's a rundown of the core features that work:

 

Built-in switchable BASIC C

Switchable RAM-under-OS/ROM OS

Switchable selftest ROM

128K 130XE mode, with ANTIC-enhance (yeah, VideoBlitz works)

320K Peterson mode

576K Peterson mode

 

Still to do:

 

The other 576K mode is slightly broken-- main memory looks fine but I have garbage starting at $5000 in each extended bank so not sure what's happening there. Although the darn simulator said it should work...

 

Figure out why my 8MB Atarimax flash cart doesn't work! I can flash one, but I can't run it. In the process of all this I realized a subtle difference on 400/800 and XL/XE that might be a deal breaker here. The 400/800 have the RAS signal where the XL/XE have PHI2. Going to have to investigate further.

 

Test PBI signals with real device. The logic is implemented for this but I need to fab a connector on another board that can plug into a RAM slot and then fire up a real PBI device (MIO). I just implemented it for the sake of completeness to have a single chip that has everything for a complete static-ram based design without needing FREDDIE, the MMU, or the EMMU.

 

Only thing missing is the HELP key...

 

Many, many, thanks to the fine folks at Satantronic for their XRAM utilty which made debugging memory problems much easier!

post-1647-1202359326_thumb.jpg

Link to comment
Share on other sites

Got the other 576K mode working.

 

As I have a few spare I/O pins left as well as some free logic cells, so I might as well add the capability for two different 1088K modes by piggy-backing another 512K static on top of the other.

 

I also want to add the Compyshop 320K mode (bringing the total number of extended memory maps to seven)-- can anyone with this upgrade in their XE confirm how bit 7 is connected? Is it latched during extra memory access? Or is the self-test ROM permanently disabled?

Link to comment
Share on other sites

  • 2 weeks later...

Hello.

 

Will this expansion be compatible with Atari 400 too? I have a friend with this machine and he seems quite interested on this expansion.

 

What differences will have against other expansions (forgetting the obvious ones) like the Mega-HZ's 576kb for Atari XL machines? What about stuff like stereo POKEY?

 

Regards.

Link to comment
Share on other sites

Hello.

 

Will this expansion be compatible with Atari 400 too? I have a friend with this machine and he seems quite interested on this expansion.

 

What differences will have against other expansions (forgetting the obvious ones) like the Mega-HZ's 576kb for Atari XL machines? What about stuff like stereo POKEY?

 

Regards.

 

This particular board design is not directly compatible with the 400 due to there being no OS board slot. This is designed to reside in the 800 personality module slot. This does not mean this is not applicable to the 400, only that it requires a slightly different board to reside in the single RAM slot instead of the OS slot. It's essentially the same logic design sans two 800 specific signals.

 

There is no difference in the expansion modes, they work exactly like a 130XE. You don't need this mod to retrofit a 400/800 with dual-POKEYs for stereo sound.

Link to comment
Share on other sites

Warerat...How do you get around the 'help key' problem (as 800's don't come with a help key, but there again, not much software uses it)

 

Also does your upgrade have a switch that switches the D301 location from xl/e mode to 800 mode (as d301 is also used for the additional two joystick ports

 

When in xl/e mode does it still recognise the D800 800 bankswitch location

Link to comment
Share on other sites

Warerat...How do you get around the 'help key' problem (as 800's don't come with a help key, but there again, not much software uses it)

 

Also does your upgrade have a switch that switches the D301 location from xl/e mode to 800 mode (as d301 is also used for the additional two joystick ports

 

When in xl/e mode does it still recognise the D800 800 bankswitch location

 

No HELP key. I'm not drilling any holes for switches for it-- I'll let someone else come up with an innovative way. A small circuit that takes a combination of keys to trigger the help key might work here. I can play Yoomp on my 800 without the HELP key so I'm happy.

 

If you're intimately familiar with the differences between the 800 and the XL, you'll appreciate the amount work I put into this to make it as unobtrusive as possible to the original design (that means that the machine will function as it did originally without any of this stuff plugged in). That being said, it's not a simple "switch" to turn the 800 into XL. I've discussed this before, if you search in the prior threads, so I'll say it again:

 

If you want 800 mode, you unplug the connector from the personality module, unplug the personality module, plug in your original 800 OS card, and plug in your original 800 memory boards. Now you're back to stock 800. In 800 mode, you run 800 software and 800-compatible hardware. In XL mode, you run XL-compatible software. That's the whole point. The new personality module switches the memory map of the 800 to XL, so no, you can't run 800 software while in XL mode.

 

You've asked this before, so I'll refer you to: http://www.atariage.com/forums/index.php?s...=84836&st=0

 

That's not to say it's impossible to do it by flipping a switch, only that I'd have to rework the existing design, and possibly move to a larger CPLD to support it. The entire premise of this when I started was to 1) Stay with Atari's original intent by allowing you to change the "personality" by swapping boards, and 2) Provide all the extended features provided by the base XL/XE and upgraded memory. I've reached those goals.

Link to comment
Share on other sites

Warerat...How do you get around the 'help key' problem (as 800's don't come with a help key, but there again, not much software uses it)

 

Also does your upgrade have a switch that switches the D301 location from xl/e mode to 800 mode (as d301 is also used for the additional two joystick ports

 

When in xl/e mode does it still recognise the D800 800 bankswitch location

 

No HELP key. I'm not drilling any holes for switches for it-- I'll let someone else come up with an innovative way. A small circuit that takes a combination of keys to trigger the help key might work here. I can play Yoomp on my 800 without the HELP key so I'm happy.

 

If you're intimately familiar with the differences between the 800 and the XL, you'll appreciate the amount work I put into this to make it as unobtrusive as possible to the original design (that means that the machine will function as it did originally without any of this stuff plugged in). That being said, it's not a simple "switch" to turn the 800 into XL. I've discussed this before, if you search in the prior threads, so I'll say it again:

 

If you want 800 mode, you unplug the connector from the personality module, unplug the personality module, plug in your original 800 OS card, and plug in your original 800 memory boards. Now you're back to stock 800. In 800 mode, you run 800 software and 800-compatible hardware. In XL mode, you run XL-compatible software. That's the whole point. The new personality module switches the memory map of the 800 to XL, so no, you can't run 800 software while in XL mode.

 

You've asked this before, so I'll refer you to: http://www.atariage.com/forums/index.php?s...=84836&st=0

 

That's not to say it's impossible to do it by flipping a switch, only that I'd have to rework the existing design, and possibly move to a larger CPLD to support it. The entire premise of this when I started was to 1) Stay with Atari's original intent by allowing you to change the "personality" by swapping boards, and 2) Provide all the extended features provided by the base XL/XE and upgraded memory. I've reached those goals.

 

No more re-working please :D

If it is XL compatible then pretty much everything that I want to do/play is available as original or hacked image. I can't actually remember using the help key at any time.

Heres to an early release of this baby :thumbsup: :D

Link to comment
Share on other sites

Update...

 

Got the Atarimax flash carts working-- needed an extra enable to the on-board decoder for the cart slots to insure proper timing. Only thing I haven't tested are PBI interface and I really haven't stressed out the latched 576K mode, although it seems to work OK and the memory tests OK running XRAM.

 

So at this point I'm convinced the design works and have "locked the pins".

Link to comment
Share on other sites

Update...

 

Got the Atarimax flash carts working-- needed an extra enable to the on-board decoder for the cart slots to insure proper timing. Only thing I haven't tested are PBI interface and I really haven't stressed out the latched 576K mode, although it seems to work OK and the memory tests OK running XRAM.

 

So at this point I'm convinced the design works and have "locked the pins".

 

GREAT NEWS!

Link to comment
Share on other sites

Warerat...How do you get around the 'help key' problem (as 800's don't come with a help key, but there again, not much software uses it)

 

Also does your upgrade have a switch that switches the D301 location from xl/e mode to 800 mode (as d301 is also used for the additional two joystick ports

 

When in xl/e mode does it still recognise the D800 800 bankswitch location

 

No HELP key. I'm not drilling any holes for switches for it-- I'll let someone else come up with an innovative way. A small circuit that takes a combination of keys to trigger the help key might work here. I can play Yoomp on my 800 without the HELP key so I'm happy.

 

If you're intimately familiar with the differences between the 800 and the XL, you'll appreciate the amount work I put into this to make it as unobtrusive as possible to the original design (that means that the machine will function as it did originally without any of this stuff plugged in). That being said, it's not a simple "switch" to turn the 800 into XL. I've discussed this before, if you search in the prior threads, so I'll say it again:

 

If you want 800 mode, you unplug the connector from the personality module, unplug the personality module, plug in your original 800 OS card, and plug in your original 800 memory boards. Now you're back to stock 800. In 800 mode, you run 800 software and 800-compatible hardware. In XL mode, you run XL-compatible software. That's the whole point. The new personality module switches the memory map of the 800 to XL, so no, you can't run 800 software while in XL mode.

 

You've asked this before, so I'll refer you to: http://www.atariage.com/forums/index.php?s...=84836&st=0

 

That's not to say it's impossible to do it by flipping a switch, only that I'd have to rework the existing design, and possibly move to a larger CPLD to support it. The entire premise of this when I started was to 1) Stay with Atari's original intent by allowing you to change the "personality" by swapping boards, and 2) Provide all the extended features provided by the base XL/XE and upgraded memory. I've reached those goals.

 

I would assume, after this upgrade, that an Atari 800 Translator disk would work just like on an XL/XE to run 800 software.

Link to comment
Share on other sites

I would assume, after this upgrade, that an Atari 800 Translator disk would work just like on an XL/XE to run 800 software.

 

since warerat designed it to have the personality module easily swapped, It would be almost as easy as swapping floppies. I would assume that it would work but you would not have joystick 3 and 4.

Link to comment
Share on other sites

I would assume, after this upgrade, that an Atari 800 Translator disk would work just like on an XL/XE to run 800 software.

 

since warerat designed it to have the personality module easily swapped, It would be almost as easy as swapping floppies. I would assume that it would work but you would not have joystick 3 and 4.

 

Correct, you'd need a translator disk to run 800 software on your 800. This is the entire XE RAM/ROM system on a board. So the only thing 800 about the 800 with this is the case.

 

There will be provisions for adding the 32-in-1 OS upgrade. However, I can't stress enough that in XL mode, ports 3/4 are not to be used at all- and I'm sure there will be some who insist on plugging a joystick into them. Beware, because they are in output mode (as opposed to input to read the joystick) and your 800 wouldn't appreciate you directly manipulating the basic, os, and memory bits with a joystick. Imagine pushing the joystick up and having the OS ROM disappear... ;)

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...