Date   : Mon, 05 Feb 1990 15:26:32 GMT
From   : swrinde!cs.utexas.edu!jarvis.csri.toronto.edu!utgpu!attcan!brian@ucsd.edu (Brian Musker)
Subject: 1793 Disk Contr. Info?

I have almost completed disassembling the ROM from my OSBORNE-I,
(I will be porting CP/M 3.0 to it), and I can't quite make sense
out of some of the data being sent to or received from the 1793
floppy controller.

Can anyone confirm the significance of these ports?

    RS1    RS0      PORT
    =======================================
     0      0       READ=STATUS, WRITE=CONTROL
     0      1       READ/WRITE= TRACK
     1      0       READ/WRITE= SECTOR
     1      1       READ/WRITE= DATA

Also, does anyone know what the STATUS/CONTROL flag values might be?

As far as I can tell, STATUS Bit 0 Is Controller Ready for read/write,
and Bit 1 is some sort of Error State.

HELP!

Brian Musker