formatting floppies

[LouisStDubois]

This doesn't have much to do with MASM, but I'm having problems formatting on this Tandy 1000 TX (80286) in DOS 3.3.  I have as my "A" drive a 5.25" and as the "B" drive a 3.5" fdd.  When I try to format with the B drive it will format the 3.5 ordinarily 720k disk as a 360k disk.  I've tried the f:/720k switch and get "invalid parameter" every time, no matter how I reconfigure the syntax.  I don't know enough about this version of DOS to be able to tell whether I'm asking it to do something it won't support.  I'm getting my "f" switch information from a manual for DOS 5.0.  I've tried to locate the various DOS capabilities by version on the net but haven't had any luck.  I've read a little about including a config.sys file to do something to possibly address this problem, but am unsure how to go about that exactly. Thanks for any help.

[sinsi]

Have a look at the "drivparm" command for config.sys - here is a link
http://www.csulb.edu/~murdock/drivparm.html

[MichaelW]

The format command for MS-DOS 3.3 does not support the /F switch, so AFAIK to format a 3.5-inch 720KB diskette, which has 9 sectors per track and 80 tracks per side, you must use:

FORMAT drive: /N:9 /T:80

[LouisStDubois]

For Michael's suggestion I got the message "parameters not supported".  When I tried the DRIVPARM command I got something like "unknown config" or something like that, so I tried this:  "DEVICE=/D:1/F:2" and got this message:  "Bad or missing D:1".  What I'm dealing with is a generic drive in a Tandy which fed its power thru the data cable.  I had to modify the data cable by cutting 5,7,9, & 11 wires and grafting those to the red or five volt wire on a generic floppy plug.  I then cut the 29,31, & 33 wires and grafted them to the yellow or twelve volt wire on the same plug.  I ran the two black wires to the shield which should be at ground potential.  However, I subsequently read in another info manual for Tandy floppies that one must cut the number two and number three wires also, so I may have a hardware problem.  I'll try that.  The 3.5 fdd will read 720k disks just fine, but when it comes to formatting, it isn't being recognized.  Thank you all for your replies.

[MichaelW]

AFAIK Format depends on the BIOS for hardware information, low-level format, and read/write operations. What does the BIOS setup show for the diskette? What do the BIOS functions, other than those that write to the diskette, return for the drive?