[Coco] Problem w/HDBDos chip

[Bill]

I have two HDBDos eprom chips that have been working beautifully with
DriveWire 4.33 for over a year in an FD-501 controller on my dual 3 ½”
drives. However, with this latest purchase of Coco “stuff”, I received a set
of dual 5 ¼” drives. I hooked up the controller with the  HDBDos eprom chip
in it, and it worked great UNTIL I tried to access the physical drives. I
typed DRIVE OFF (which had been working on this very computer), and all I
got was NOTHING. The drive light came on, but that was it. And the disk
worked perfectly with another FD-501 controller with original RS-Dos in it.

 

Ideas? What more info do you need to hazard a guess?

 

Thanks