Re: D9060 Help Needed

From: William Levak <wlevak_at_sdf.lonestar.org>
Date: Fri, 11 Dec 2009 06:03:35 +0000 (UTC)
Message-ID: <Pine.NEB.4.64.0912110537350.26858@sdf.lonestar.org>
On Thu, 10 Dec 2009, Mike Naberezny wrote:

> Hi Jim,
>
> On 11/30/09 10:06 AM, Jim Brain wrote:
>> I mainly wanted one so I can see how CBM planned HDD storage (I have
>> noticed an addition ',1' on the end of error strings, but maybe that's
>> just BASIC 4.0's ?ds$ doing that.)
>
> I have noticed that CBM DOS 2.7 (8250 and SFD-1001) returns an extra number 
> after the track and sector.  I've never read anything about this but I 
> believe it is the last-accessed drive number (0 or 1).

Correct.

> This can even be seen on the SFD-1001, which is a single drive.  If you try 
> to access the second drive on an SFD-1001 with DIRECTORY D1 or similar and 
> then PRINT DS$, you'll get "74,DRIVE NOT READY,0,0,1".  You'll get the same 
> result using the equivalent BASIC 2.0 commands.

The SFD-1001 and 8250 use the same DOS ROMs.  The controller ROM on the 
SFD-1001 returns a "DRIVE NOT READY" condition if you try to access the 
non-existent drive 1.

> The D9090 may have the same behavior and you accidentally accessed drive 1, 
> or it perhaps it has a different meaning that is specific to DOS 3.0.

The "Commodore Disk Reference Manual for D9090 D9060 8250 8050 4040 2031"
does not mention the "extra" number for the D9090/60, but it probably does 
mean the same thing.


wlevak@sdf.lonestar.org
SDF Public Access UNIX System - http://sdf.lonestar.org

       Message was sent through the cbm-hackers mailing list
Received on 2009-12-11 07:00:03

Archive generated by hypermail 2.2.0.