[comp.sys.dec] RD53 who thinks it is a RD51

terry@spcvxb.spc.edu (Terry Kennedy, Operations Mgr.) (05/28/91)

In article <1991May20.194041.18402@athena.mit.edu>, prg@athena.mit.edu (Patrick R. Griffin) writes:
> My questions are:
> (1) Where does the system get the information about what type of disks
>     are attached to it?

  The RQDX1 and 2 issue assorted illegal commands to the drive to guess the
number of heads and cylinders. The RQDX3 writes geometry information to the 
disk when it's first formatted, and then reads it every time an MSCP online
command is issued to the disk.

> (2) What can be done to convince the system that the disk in question really
>     is a RD53?

  If this is on an RQDX1 or 2 (unlikely as you mentioned 3 disk drives), it
is probably a drive problem, most likely in the logic board. If the control-
ler is an RQDX3, it could be a simple loss of format, or it could be a logic
board problem as in the RQDX1/2.

	Terry Kennedy		Operations Manager, Academic Computing
	terry@spcvxa.bitnet	St. Peter's College, US
	terry@spcvxa.spc.edu	(201) 915-9381