Agilent Technologies 35670A Service Manual page 379

DIR
DISKINn
DRIVESELn
DSKCHGn
HDSEL
HIDENSn
INDEXn
MTRn
ReDATAn
SEL0 - SEL1
STEPn
T00n
WDATA
WGATE
WRIPROTn
Agilent 35670A
Direction — This line sets the direction for the disk head. A high on this line sets the direction
away from the spindle. A low on this line sets the direction toward the spindle.
Disk In — This line goes low when a flexible disk is inserted in the A100 Disk Drive assembly.
Drive Select — A low on this line selects the A100 Disk Drive assembly.
Disk Change — This line goes low when a flexible disk is removed from the A100 Disk Drive
assembly. This line remains low until a flexible disk is installed and STEPn goes low.
Head Select — A low on this line selects the lower disk drive head. A high on this line selects
the upper disk drive head.
High Density Select — This line goes low when a high density flexible disk is inserted in the
A100 Disk Drive assembly.
Index — This line pulses low with each revolution of the flexible disk.
Motor On — A low on this line turns on the disk drive motor.
Read Data — This line pulses low for each bit detected on the flexible disk.
Drive Select — When SEL0 and SEL1 are low, the A100 Disk Drive assembly is enabled.
Step — A low on this line moves the disk drive head. When STEPn and DIR are low, the head
moves toward the disk spindle. When STEPn is low and DIR is high, the head moves away
from the disk spindle.
Track 00 — This line is low when the head is positioned over track 0 on the flexible disk.
Write Data — When WGATE is low, a low pulse on this line writes a bit to
the disk.
Write Gate — When this line is low, information may be written to the A100 Disk Drive
assembly under control of the WDATA line.
Write Protect — This line is low when a write-protected disk is installed in the A100 Disk
Drive assembly.
Voltages and Signals
A100 Disk Drive
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