[Coco] Help booting OS-9 L2

[Shawn Hedgecorth]

Hello everyone,
I am having problems booting OS-9 L2. Today is the first time in 14 years
that I have done anything with OS-9. I am using a 512K CoCo3 and a Disto
SC-II. When I type DOS, it starts the boot process (OS-9 Boot screen is
visible), the head moves a couple of tracks, and then nothing else seems to
happen. The disk that is being used is a backup of a Tandy original. I kind
of remember having a problem using L2 on a SC-II if the boot disk had not
been patched (just vaguely remember that). I also have a J&M controller. The
problem with the J&M controller is that the DOS command doesn't seem to work
(I get a ?FN ERROR). I remembered that some of the early OS-9 games had a
BASIC loader to start the OS9 Boot. I loaded one of the boot loader programs
 put the OS-9 Boot disk in drive 0, type RUN, and it works just fine (on the
J&M controller, not the Disto SC-II). I then created a new boot disk using
the patch disk from Disto. When I try using the new boot disk, I am right
back to square 1. What am I forgetting?

Shawn Hedgecorth