Does DOS 2.5 really support 4 drives?

[bugbiter]

I've been wondering for a long time..

 

All the Atari computer and drive manuals say that up to 4 drives can be connected to the Atari and after all you can set 4 different drive numbers with the switches on the back of the drives.

But I can only acces D1: and D2. with DOS 2.5. I get an Error 160 with drives 3 and 4. Am I doing something wrong?

Or is it true that Atari's own DOS never supported 4 drives?

[Madi]

From Mapping the Atari, Chapter 17:

 

"DOS 2.5 supports drives 1-8, but

is initialized to drives 1, 2, and 8, so if you have other drives, change
location 1802 ($70A); that is, if you have three drives and the
RAMdisk, POKE 1802, 135. All bits in location 1802 now represent possible drives."

Binary (‭10000111‬)

for 4 drives and Ramdisk= 143 ($8F) (10001111)

 

See this topic

madi

Edited September 8, 2016 by Madi

[Roydea6]

goto basic and type

 

POKE 1802,15

 

goto back to DOS

 

use the 'H' option

 

1

y

[+kheller2]

Keep in mind this allocates buffers for those drives and your RAM footprint will be reduce appropriately

[fujidude]

Keep in mind this allocates buffers for those drives and your RAM footprint will be reduce appropriately

 

Thus why it isn't just always enabled that way.