ZiLOG System 8000 Hardware Reference Manual

HRM 21
2ilog
HRM 21
B.14. Format Verify / UNIT / HEAD / CYLINDER /
This is a diagnostic command that verifies the integrity of
the disk format on a track. The controller reads each indi-
vidual sector of the track and ensures that its header is
good. If a format error is detected, the Verification Error
bit is set in the Operation Error status Byte and the Unre-
coverable Error on Operation bit in the Operation Ending
Status. byte is set.
/ UNIT / Unit is written to the controller through CP1. Any
value between zero and three is valid.
/ HEAD / Head is written to the controller through CP2.
/
CYLINDER / The target cylinder number is written to the
controller through command ports CP3 and CP4. The low order
eight bits of the ten-bit cylinder address are issued to the
controller through CP3 and the high order two bits are
issued through CP4 bits zero and one.
B.15. Unit Format Verify / UNIT /
This is a diagnostic command. It is used to verify the for-
mat of an entire unit. If a format error is detected, the
Verification Error bit is set in the Operation Error Status
Byte, and the Unrecoverable Error on Operation bit in ~he
Operation Ending Status Byte is also set. The cylinder
where the failure occurred is read back by the Read Detailed
Status command.
/
UNIT / Unit is written to the controller through CP1. Any
value between zero and three is valid.
B. 16. Commclnd Notes
An explicit format write command is not provided in the
controller's command repertoire. All disk write operations
write the sector address field as well as the data. There-
fore, a write sector command performs a format write opera-
tion.
B-6
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B-6

ZiLOG System 8000 Specifications

General

Brand	ZiLOG
Model	System 8000
Category	Desktop
Language	English