OS dumps & ATARI Translator

[Ricky Spanish]

So we can dump the computers OS, yet, can't upload them the same way, so how does the ATARI TRANSLATOR DISK upload the 400/800 OS to our XL computers?

I know it blocks the factory OS and places the 400/800 OS into ram. But that's all I know. Asking cause I think it would be nice just to upload an OS without having

to buy different hardware / replace chips etc. Thanks. 

[TGB1718]

It would need to load the OS into low RAM so no need to access the disk via OS during the install, then

switch out the OS and copy the replacement OS up to the correct location.

 

Did something similar for a printer driver, copied the OS to RAM, switch out the OS, copy the OS back

to RAM, make changes to the OS now resident in RAM, printer driver with no extra RAM usage

 

 

[Rybags]

You can copy the OS to Ram and modify it in place.  Or have one you load from disk to replace the stock OS.

Running an OS from RAM has the risk of being overwritten.

Translator OS I believe does have some modifications though minor.

 

You need a code stub in lower Ram so that your replacement OS survives a warmstart (reset).

Modifications needed to the OS would be such things as making sure the top of memory test doesn't exceed address $BFFF.

 

For testing purposes it's handy to be able to load a different OS.  But in the real world you'd still want one on switchable flash or Eprom.

[ACML]

If you want to directly load the Atari 400/800 OSa or OSb or Omniview 80 OS, try these:

 

Atari XL to OSB Translators.ATR Omnivew 80 Disk Version.atr Rev-A OS.xex Rev-B OS.xex XL to 800 Emulator.xex

[Ricky Spanish]

55 minutes ago, ACML said:

If you want to directly load the Atari 400/800 OSa or OSb or Omniview 80 OS, try these:

Actually I want to place 1200xl rev11 OS into my 1200xl. But I'm sure those are very useful for those that need it !

[Rybags]

Something I forgot - with the XL OS you'd have a hard time with Self-Test and possibly the 1200XL rainbow logo.  The switchable part that loads at $5000 is right in the middle of main Ram, so having that reside there isn't very practical.

I suppose in lieu of BYE you could probably have it as a loadable binary file.

[Ricky Spanish]

On 8/28/2022 at 8:15 PM, Rybags said:

Something I forgot - with the XL OS you'd have a hard time with Self-Test and possibly the 1200XL rainbow logo.  The switchable part that loads at $5000 is right in the middle of main Ram, so having that reside there isn't very practical.

I suppose in lieu of BYE you could probably have it as a loadable binary file.

Is rev 10 and rev 11 that much different ? AFAIK all the memory locals are the same. 

[+DrVenkman]

1 hour ago, Ricky Spanish said:

Is rev 10 and rev 11 that much different ? AFAIK all the memory locals are the same. 

In my limited tests, rev 11 is more compatible than rev 10 with some earlier 400/800 software. Had the 1200XL not been canceled so abruptly it would have undoubtedly become the standard. It's not that hard at all to put into real hardware with a pair of 8Kb EEPROMs and a little bit of minimal hardware work if necessary to reconfigure some motherboard jumpers.

 

 

 

[Ricky Spanish]

14 minutes ago, DrVenkman said:

In my limited tests, rev 11 is more compatible than rev 10 with some earlier 400/800 software. Had the 1200XL not been canceled so abruptly it would have undoubtedly become the standard. It's not that hard at all to put into real hardware with a pair of 8Kb EEPROMs and a little bit of minimal hardware work if necessary to reconfigure some motherboard jumpers.

 

 

 

Did you make those ?

[+DrVenkman]

1 minute ago, Ricky Spanish said:

Did you make those ?

The two EPROMs? Yep. 

[Ricky Spanish]

38 minutes ago, DrVenkman said:

The two EPROMs? Yep. 

You willing to make a couple more ?  

[+DrVenkman]

9 minutes ago, Ricky Spanish said:

You willing to make a couple more ?  

Unfortunately I don't think I have any more compatible EPROMs. And mailing them to Canada would be probably be more expensive than it's worth, lol. I expect there's got to be someone around here who can use domestic Canada Post for you.   

There's a whole thread around here from two-three years ago that has the details on how to do the conversion. It's a lot simpler if your 1200XL came from the factory with EPROMs already, which some did. All three of mine came with mask ROMs though, so I didn't have that luck.

 

 

[Ricky Spanish]

3 minutes ago, DrVenkman said:

Unfortunately I don't think I have any more compatible EPROMs. And mailing them to Canada would be probably be more expensive than it's worth, lol.

Everything I bought cames outta the states lol. The 256k DRAMs / Sdrive Max / UAV / 256 RAMBO. Except for my Hercules cables. Even then I still had to pay USD haha.

[+kheller2]

From kr0tki’s documents on every OS version:

“

Rev. 11 was developed by Robert Scott Scheiman,[38], and it fixed several problems of the previous revision with function of the Reset key.[29] The order of routines was also changed, apparently to fit in a few unofficial OS vectors for better compatibility with programs designed for the 400/800 OS revisions. The most noticeable difference is in the power-up display - in rev. 11 an ® mark was added to the Atari logo.

 

”

[Ricky Spanish]

7 minutes ago, kheller2 said:

and it fixed several problems of the previous revision with function of the Reset key.

What's the problem the RESET key ?

[_The Doctor__]

the 1200xl had some reset issues that I believe bob1200xl or was it? that addressed hardware issue for the reset circuits and timing (cap? chip?) and the rev 11 OS addressed the issues as best it could in the firmware (OS ROM/prom)

[Rybags]

From a quick look - Rev 10 doesn't have the soft delay loop on cold/warmstart.

The delay exists in all future OS releases and I would say the reason is as a Reset key debounce.

There is s short time where the OS clears Page 3 which contains the magic number sequence indicating the machine has already had a coldstart.

If those numbers aren't present the OS assumes a coldstart is required.  A bouncing key or the user pressing Reset twice with the right timing can cause a (usually unwanted) coldstart.

 

With practice I was able to generate a coldstart this way on my 800XL probably better than 1 in 10 attempts.  I guess without this delay it could have been a problem on the machines with that OS revision.

[_The Doctor__]

sounds about right.