[Coco] Can't copy real floppy to CoCo-SDC on a CoCo 2

[mike at borncoco.com]

I've managed to alter the issue slightly, but the BACKUP command still will not work between the CoCo-SDC and a real floppy on my CoCo 2.

I have removed one of the floppy drives. The remaining drive appears to be a Tandon TM-65L. There is a terminating resistor pack installed (RP1), the DS jumper is set to D0, and I'm using a straight flat ribbon cable and the drive is connected to the last connector on the cable.

I issue DRIVE 0,OFF and I can access the real floppy as drive zero. I can do a dir and load programs from the real floppy without issue. Likewise, I have a DSK image mounted from the SD-card as drive 1 and I can also do a DIR, SAVE to drive 1 without issue. Now, if I attempt to do a "BACKUP 0 TO 1" I now get an "?IO ERROR" instead of "?SN ERROR". SDC-DOS still seems to be working, but for some reason, the BACKUP command fails. When I issue the "BACKUP" command, it starts to read the real floppy. The LED on the CoCo-SDC never lights up. Any ideas on what's happening or further troubleshooting ideas?

Cheers,
-Mike Rowen


-----Original Message----
From: "Robert Gault" <robert.gault at att.net>

Coco drives are addressed by the cable not be jumpers in the drive. If you have 
such jumpers, they probably should be set to 0.
There should be only one terminator resistor block in your system. If more than 
one drive has such, the last (highest number drive) should have the resistors.

PC drives may not be able to be used as drive0 without a twist in the cable. 
Such a drive probably will work as drive1 without changes to the cable.

Robert