[comp.os.vms] Limit on Microvax MSCP controllers?

ken@HAMLET.CALTECH.EDU (Kenneth Adelman) (04/30/87)

	Does anyone know if there is a limit on the number of MSCP
disk controllers which one can place on the Microvax II Qbus?

	We have a Microvax II with the standard RD53 drive and are
trying to add two Spectrologics MSCP-to-SMD controllers each running
two eagles, and run into the following problems:

1) The CSR address on the spectrologics controller can only be set to
   the address that VMS expects to find the first or second MSCP
   controller. It can be set to other addresses, but AUTOCONFIGURE ALL
   obviously doesn't find it.

2) When connected by hand the PUC0 UCB appears, but no DUCx devices.
   PUC0 is online, and appears to be talking to the controller.

	If the RD53 controller is removed, the spectrologics controllers
work just fine as numbers 0 and 1. Any ideas?

							Kenneth Adelman
							Caltech