OS larger than 16kB

[flashjazzcat]

35 minutes ago, thorfdbg said:

Any kind of hard disk handler will take even more of my precious RAM.

For info: the PBI driver consumes no system RAM at all. PBI devices usually include their own ROM and RAM which is typically mapped underneath the FP ROM ($D800-$DFFF) or in the $D1xx region.

[_The Doctor__]

thorfdbg the whole reason the original 800 had a dual floating bus with slots continuing the evolution but not entirely migrating across the 1000 series through the 1400's and ending up with a (the) PBI OS we currently have was and is so we would not use up system RAM and could swap out the area with whatever pbi ID device that needs it at that time. This is why the MIO can swap in and out without damaging anything, same as the CSS black box (though it eats all ID's). This window or keyhole allows the OS the be altered transparently(for the most part) by the connected device. It won't eat your ram or other resources, the benefits have been instrumental in allowing the A8 to reach some of it's potential and is being used by many of wonderful, indispensable products (New as well as Old).

 

I glazed over and hope if it's not too much trouble to explain what's at issue, I miss quite a bit these days... the vultures circle...

please clarify for my benefit in some other way what's bad about the pbi portion of the Atari OS so I can understand, do we need to modify or change it in some way?

Edited February 7, 2021 by _The Doctor__

[thorfdbg]

On 2/5/2021 at 8:53 PM, flashjazzcat said:

For info: the PBI driver consumes no system RAM at all. PBI devices usually include their own ROM and RAM which is typically mapped underneath the FP ROM ($D800-$DFFF) or in the $D1xx region.

The corresponding DOS does, or whatever was booted through the PBI functions - or the DOS in general. I found this quite annoying back then that you always needed to boot the Dos from the floppy, and that it took RAM away from the user. Thus, from the 64K of RAM the system had, only half of it was left for the user. A harddisk wasn't an option for most users back then - instead, Atari should have integrated a suitable DOS into the extended ROM. That would have been much more beneficial to most users than the PBI - for which no equipment existed while Atari was selling the XL line.

[thorfdbg]

23 hours ago, _The Doctor__ said:

please clarify for my benefit in some other way what's bad about the pbi portion of the Atari OS so I can understand, do we need to modify or change it in some way?

I would not call it "bad". Just "under-documented" and "over-engineered" and "bulky". It partially could replace SIO functions, also CIO functions, it also had a relocatable loader, and a HATABS extension. Yet, for most users at its time, it was left unused, and just took away precious ROM space.

[flashjazzcat]

22 minutes ago, thorfdbg said:

The corresponding DOS does, or whatever was booted through the PBI functions - or the DOS in general.

I guess, but most productivity software is written with DOS in mind, since DOS has been around since the 400/800 and no non-relocatable application or driver would be assembled to an address lower than $1F00 unless the intention is to severely limit the user base. And as neat as it might be to have DOS built into the OS, there is a limit to what facilities can be achieved using this approach. I don't see any reason why you couldn't implement a PBI-based DOS, with all ROM and RAM (for buffers, etc) wholly contained on the external device. No code size limits and as much functionality as you want with absolutely the bare minimum of system RAM used.

22 minutes ago, thorfdbg said:

That would have been much more beneficial to most users than the PBI - for which no equipment existed while Atari was selling the XL line.

Probably so, but it's now 2021 and we have an increasinlgly large number of peripherals and upgrades which leverage the PBI. Large extended memory upgrades are highly prolific, as are hard disk host adapters. Any OS which doesn't support them is now limiting its audience.

Edited February 8, 2021 by flashjazzcat

[thorfdbg]

49 minutes ago, flashjazzcat said:

And as neat as it might be to have DOS built into the OS, there is a limit to what facilities can be achieved using this approach.

Would a Dos 2 compatible Dos with a command line interface, designed for the 1050 work? IOWs, everything a RAM-based DOS could achieve can be done. Frankly, if I want a hard disk....well, there are certainly other systems that take more profit from it. The Atari 8 bit is just a nice legacy game machine.

[+Stephen]

32 minutes ago, thorfdbg said:

The Atari 8 bit is just a nice legacy game machine.

That is not true for many of us that use these machines.  Hard drives were available as far back as 1983.  If all you want is a game machine, get a 5200.  You don't need a keyboard, SIO port, any kind of expansion, etc.

[flashjazzcat]

1 hour ago, thorfdbg said:

Would a Dos 2 compatible Dos with a command line interface, designed for the 1050 work? IOWs, everything a RAM-based DOS could achieve can be done. Frankly, if I want a hard disk....well, there are certainly other systems that take more profit from it. The Atari 8 bit is just a nice legacy game machine.

I feel we are in danger of straying away from the original point. You asked who could possibly require PBI support in the OS (which you seemed to consider unnecessary): the answer is probably a four-figure number of U1MB/Incognito and HDD host adapter users. Even SDX users without a hard disk of any kind can benefit from U1MB/Incognito PBI-hosted high-speed SIO driver (one must otherwise explicitly instruct SDX to use the OS SIO routines, assuming the OS has divisor 0 capabilities built into it). I've explained that PBI handlers do not consume main memory and that any application designed to use a file system will generally avoid the RAM typically used by DOS, but if you simply consider OS-agnositic high-speed SIO and mass storage devices with hierarchical file systems completely unnecessary on the platform, then certainly no PBI support and a built-in DOS 2 file system will suffice. Many others will see the situation quite differently.

Edited February 8, 2021 by flashjazzcat

[Mark2008]

4 hours ago, Stephen said:

That is not true for many of us that use these machines.  Hard drives were available as far back as 1983.  If all you want is a game machine, get a 5200.  You don't need a keyboard, SIO port, any kind of expansion, etc.

Preach it!

 

Btw, this topic just makes me recall the Liber809, which I believe you can still buy, and lets you use Nitros-9 on an atari.  

CPU swap is a big deal, no doubt, but true multi-user multitasking, sweet!

[phaeron]

8 hours ago, thorfdbg said:

I would not call it "bad". Just "under-documented" and "over-engineered" and "bulky". It partially could replace SIO functions, also CIO functions, it also had a relocatable loader, and a HATABS extension. Yet, for most users at its time, it was left unused, and just took away precious ROM space.

The relocating loader is not part of the Parallel Bus Interface. It was added in the 1200XL OS prior to the PBI and is not needed to run PBI devices. The design of and support code for PBI devices is considerably simpler than that for loadable/relocatable handlers.

[thorfdbg]

On 2/8/2021 at 9:48 PM, flashjazzcat said:

 I've explained that PBI handlers do not consume main memory and that any application designed to use a file system will generally avoid the RAM typically used by DOS, but if you simply consider OS-agnositic high-speed SIO and mass storage devices with hierarchical file systems completely unnecessary on the platform, then certainly no PBI support and a built-in DOS 2 file system will suffice. Many others will see the situation quite differently.

Look, I consider it rather telling that Atari itself never produced a device that used their own interface. When they provided new hardware, they rather used the joystick ports - consider the kludgy XEP-80. The whole thing solved a problem nobody had back then. It became somewhat relevant later with third-party additions, but at that time, Atari had given up the platform already.

 

To boot from an external parallel device, a considerably simpler construction would have been possible - just a small SOI patch-up or an improved bootstrap would have done.

 

[flashjazzcat]

8 minutes ago, thorfdbg said:

Look, I consider it rather telling that Atari itself never produced a device that used their own interface.

8 minutes ago, thorfdbg said:

Atari had given up the platform already.

Observation and explanation.

10 minutes ago, thorfdbg said:

To boot from an external parallel device, a considerably simpler construction would have been possible - just a small SOI patch-up or an improved bootstrap would have done.

I had completely failed to mention what Avery pointed out already: that the relocating loader is not even necessary for PBI device support. If you look at the code in Avery's OS which actually polls for and invokes PBI device handlers, you'll see how concise and uncomplicated it is.

 

As said: whether Atari exploited it or not, the PBI/ECI is quite widely utilised today, and not before time.

[_The Doctor__]

600XL 1064 expansion board

1090 expansion (though cancelled)

pbi diagnostic board for the 800XL

eci cart pbi diagnostic board for the 130XE

ICD MIO within 4 years CSS immediately after that

internal test sets and fixtures

manufacturing test fixtures.

modern day stuff like larger memory expansions across the lines, diagnostics like syscheck, as well as a multitude of storage solutions both hard disk and floppies and on and on...

yeah I think we've got it going on.

there were mods for the 800 and the 1200XL to add the bus to them...

with incognito the pbi is also supplied on the 800...

 

This is just what popped into my head in seconds.... I sure there is much more I haven't mentioned and though I've made mention of previously, like custom manufacturing/factory pbi interfaces and cards... cable television system units... many more. Yes the 800line the XL line the XE line ran factories, cnc machines, you name it. Some were PBI some were bus, some sio, and some i/o port... and some utilized all of the above.

 

It's safe to say PBI was used very much by both the earlier home Atari users as well as those in Professional settings, not to mention the Factory floor...

I really have to agree that if someone thinks all of this and the pbi should be tossed out, perhaps they really should consider the 5200 as their main machine... oh but wait there is the expanded 5200 cartridge path and what's that... there is a connect and port for expansion on the 5200 as well... oh no...

Edited February 11, 2021 by _The Doctor__