[comp.sys.dec.micro] Rainbow double-sided disks

rgt@LANL.GOV (Richard Thomsen) (05/10/88)

Sorry for the repeat, but I have received some inquiries about my patches
and I cannot reply to the mail addresses.

	I modified the Rainbow BIOS and Z-80 routines to allow me to put
double-sided disks on my Rainbow.  I did this since my Rainbow drives failed,
and I purchased double-sided Shugart drives for replacements.

	There were no hardware modifications to be made, other than making
cables for the disks.  The pin assignments were backwards, so I had to twist
the cables.

	Since the Z-80 controls the disks, I first had to modify the Z-80
code to allow double-sided disks.  Then I had to modify the Rainbow BIOS to
call the Z-80 code correctly.  Then I modified the MS-DOS bootstrap code
and floppy disk bootstrap code to allow booting from double-sided disks,
and the Format program to allow me to format double-sided disks.  This has
all been done, and I have been using it for over a year now.

	Sorry I cannot send it to you, since it is DEC copyright code
and I do not have DEC permission to send it out.  DEC never would talk to
me to give me such permission.

	I can send out patch files, if there was some sort of patch program
that could be used.  I would need some means of making the patch files and
some program that allows the patch files to be added to the existing DEC
files.  If you hear of any such thing, I would be interested.

	I received the PATCH program off the net a while ago, but have not
had time to look at it to see what it does.

						Richard Thomsen
						rgt@lanl.gov