Panasonic JB-3300 Technical Manual page 428

C.
d.
Clock output
(1)
(2)
Read
(2)
2FC (2F-CLOCK)
This is the clock signal output by the 4F clock when set to
2-minute cycles. :
RCK (READ-CLOCK).
During the read operation, the READ-CLOCK pulse is output by the
VCO-CLOCK. The READ-DATA signal is output synchronous to the
READ-CLOCK pulse. At times other than during the read operation,
the 2F clock's negative signal is output. 2F clock signal switch-
ing is set temporarily by the high level signal.
RAW DATA input and the DRIVE SELECT signal (RR1, RR2, and DS1) are
used to input the receiver output for the data sent from the disk
drive. The DSI signal 1s used to select between the RR1 and R2
Signal. Their correlation is shown below.
DSL RR1 & RR2
Low level Selects RRL
High level | Selects RR2
(The leading edges of RR1 and RR2 are based on risen pulses. This
is set by the disk drive.)
control signals
RGT (READ-GATE)
This control signal is a HIGH ACTIVE gate signal for all read
operations.
AEO (AM-ENABLEO)
"Also a HIGH ACTIVE signal, this is active when needed for searching
for missing block data (address marks). This signal -is active not
only during read operations, but also, in combination with the
active AMW signal, is active to enable writing of index marks.
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