ZiLOG System 8000 Hardware Reference Manual page 267

HRM Zilog
HRM
4) The SEEK packet command is issued with CY
=
-1. This
forces the disk drive to rezero and clears any drive
fault. This step prevents spurious soft rezero errors
during the first packet command issued by diagnostics.
NOTE
SMDMON is a special trouble-shooting diagnostic.
It does not abort if an error occurs during the
start-up procedure. It assumes that all disk
drives will be tested, and it attempts to SELECT
and SIZE all four possible SMD drives. It does
not issue the SEEK command.
SMD DIAGNOSTIC ERROR MESSAGES
During the start-up procedure SMD diagnostics may display
and log the following error messages:
NO RESPONSE to controller command, SMD CMD
=
xxxx
SMD controller did not respond to a command in the
initialization sequence. The commanrl written to
the SMD controller Command Register replaces xxx x
(hexadecimal) .
During controller initialization, commands are
written to the controller ·command regi.ster, and
the
~tatus
register is polled until.the command is
complete. If the status register contains "FFFF",
the controller is not responding to the command.
This usually indicates that there is no controller
board or the board is not seated properly.
TIMEOUT waiting for Controller Not Busy, SMD CMD
=
xxxx
SMD controller did not complete a command in a
reasonable time. The command was issued in polled
mode. The command written to the SMD controller
command register replaces xxxx (hexadecimal).
TIMEOUT waiting for SMD interrupt, Packet cmd
=
cc
A command was issued in interrupt mode, but no
interrupt occurred within a reasonable time. Dur-
ing the initialization sequence, the SELECT, SJZE
and SEEK commands are issued in interrupt moae.
The opcode of the packet command issued replaoes
cc (hexadecimal). The opcodes of these packet
commands are:
A-36 Zilog
A-36