SIO2SD Format / DOS XL disc buffers

[+slx]

I have finally managed to update my SIO2SD to the latest (3.1RC2) firmware and to create an EMPTY disc in D2:

Trying to Format that Disc from DOS XL results in SIO2SD showing a new ATR file but DOS XL shows an access error and does neither fully format nor otherwise access the new .ATR (which is shown mounted to D2: on the display.

 

As the DOS XL is my workig copy from the 80s it might have been configured (patched?) to be used on a single drive only to save buffer memory. Unfortunately I didn't find any online reference on how/where to set/POKE what to ensure enough buffers to use more drives.

 

Is there such a thing for DOS XL?

 

Thanks for any hints - especially a manual link!

 

 

[Rybags]

I would think it should be the same as Atari DOS 2.x

 

$70A - drive enable bits (bit 0 = drive 1)

$709 - # of sector buffers allowed

 

Just downloaded it, and that seems to be right for DOS XL 2.2.

Not sure if change takes effect straight up or you have to write DOS back to disk though.

Edited September 21, 2014 by Rybags

[+slx]

Googled the OS/A+ manual in the meantime and it's the same locations. I have 6 file buffers and 2 discs enabled. Still there's the "blowing" (phhht) sound when I try to access D2 in any way.

 

Any idea what else might be faulty. Is there a "write protect" in SIO2SD?

[Rybags]

You have to make sure the image is mounted to D2: on the SIO2SD.

Not sure about write protect - probably yes for the physical switch on the card, unsure if it adheres to the FAT read-only attribute or that in the ATR.

But if the device itself has created the image file then it should be r/w.

[+slx]

I booted DOS XL 2.30p from the Strotmann wiki on Atari800MacX and tried to access the newly created .ATR mounted as D2: and still get the "write protected" error. I checked that the .ATR file is read/write for OS X.

 

I just found that SIO2SD has a "write protect" option via the SETUP menu. I'll need to look up whether that is set to "permanent write protect" (although that would still not explain why I can't write to that ATR on the emulator.)

 

Any hints on where the write protect flag of an ATR is?

[Roydea6]

Byte F on the ATR header / If one(1) then write protect / if zero(0) then not protected..

[+slx]

Byte F on the ATR header / If one(1) then write protect / if zero(0) then not protected..

Thanks!

[+slx]

Checking the .ATR created by SIO2SD with a hex editor showed it to be empty. I have now created an empty .atr with Atari800MacX and will try to write to that using SIO2SD tomorrow.

 

Is SIO2SD supposed to "expand" an empty .atr when it is written to?

I need to learn Polish....

[Rybags]

An ATR when created shouldn't be empty, it should have a header which needs descriptors like which sector size and # of sectors in use, then zeroes in the data portion.

If it's coming up with file length 0 then something's wrong... unless somehow it's only initialized once you mount it but I doubt it'd work that way.

[+slx]

It seems to have the header only and nothing thereafter, not even zeroes. The length (paragraph) info in the header matches the zero length file, indicating zero length. So I suppose the SIO2SD firmware is at fault. It works great when I copy an emulator-created ATR onto the SD card and those match your description. A header showing the right length and then lots of zeroes.