Sun Microsystems Sun Blade 1000 Service Manual page 266

TABLE B-19
Pin
10,
12
16
18
20
22
24
26
28
30
B-22 Sun Blade 1000 and Sun Blade 2000 Service Manual • January 2002
Diskette Drive Connector, J1801, Signals and Functions (Continued)
Signal Name
DRIVE_SELECT
MOTOR_ENABLE
DIRECTION
STEP
WRITE_DATA
WRITE_GATE
TRACK0
WRITE_PROTECT
READ_DATA
Function
When set true, DRIVE_SELECT enables the drive to
respond to other input signals.
When set low, MOTOR_ENABLE initiates the
spindle motor rotation.
When active high, DIRECTION indicates movement
of the magnetic head assembly toward the outer
cylinders. When active low, DIRECTION indicates
movement of the magnetic head assembly toward
the inner cylinders.
On the trailing edge, STEP moves the magnetic head
in the direction specified by DIRECTION at a rate of
one cylinder per pulse.
WRITE_DATA supplies the disk drive with the data
to be written to disk, provided the WRITE_GATE
signal is active low.
When active low, WRITE_GATE enables the drive
write circuits. When active high, WRITE_GATE
enables drive read circuits.
When active low, TRACK0 indicates that the track
zero sensor has been activated and that the heads
are over the outermost cylinder.
When active low, WRITE_PROTECT indicates that
the inserted diskette is write-protected and that
drive write operations are disabled.
When active, READ_DATA enables data from the
disk to be transferred to the host through this signal
line.