[Color Computer] [coco] Hard drive driver and dd for Nitro9

[Robert Gault]

OK, 246 is a generic error meaning more or less "I can't see the drive 
so what the heck are you trying to do?" Could be caused by almost 
anything from a power supply problem to software.

TOS is sectors per track zero. It certainly needs to match what is on 
the drive but should not give a 246 (not ready) but 249 (wrong type) or 
maybe 247 (seek error). I think the only point to TOS is for extra large 
FAT tables.

Can we assume that the hard drive works correctly with RGBDOS or HDBDOS? 
That would eliminate many possibilities for error from consideration. 
Are you confident that the hard drive has a correctly formatted OS-9 
section? Can you look at LSN0 for the OS-9 section under Disk Basic to 
confirm that an OS-9 section has been formatted?