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Table 5-5. SIGNAL SELECT IC511 SN74HC153 Truth Value Table
Mode/
Playback
Analog recording
Digital recording
Select Input
Pin
!¢
(A)
L
H
L
H
G
Pin
2
(B)
L
L
H
H
G
STROBE
Pin
!∞
L
L
L
L
H*
1
*1) When RX PLL is unlocked or Pin #¡ (XLM) of the main
microprocessor (IC501) is “L” during digital recording, it
becomes “H” and the output of Pin 9 becomes “L”.
becomes “H” and the output of Pin 9 becomes “L”.
Table 5-5
shows the table of truth values of the selector (IC511) used during signal switching of each
mode. This switching is performed by the switching signals output from Pin !∞ (XANA/DIG) of the
main microprocessor (IC501) and Pin !§ (XREC/PB) according to the timing of LR01 (15BCK delay
signal of LRCK) via D-FF (IC512). Switching of analog/digital (H : digital, L : analog) is performed by
the output from Pin !∞ of the main microprocessor and switching of recording/playback (H : PB, L :
REC) by the output from Pin !§. When Pin !∞ (STROBE) of the selector (IC511) is “L” when the mute
output output from Pin #¡ (XLM) of the main microprocessor is STOP or during the search mode, or
when Pin #¡ (UNLK) of DAT DSP (IC503) is “H” when RX PLL is in the unlocked state during digital
IN recording (Pin 9 of the main microprocessor (VCOEN) is “H”), “H” is input and the output of Pin
9 is set to “L”.
The flow of the signals in each mode is described in the following.
main microprocessor (IC501) and Pin !§ (XREC/PB) according to the timing of LR01 (15BCK delay
signal of LRCK) via D-FF (IC512). Switching of analog/digital (H : digital, L : analog) is performed by
the output from Pin !∞ of the main microprocessor and switching of recording/playback (H : PB, L :
REC) by the output from Pin !§. When Pin !∞ (STROBE) of the selector (IC511) is “L” when the mute
output output from Pin #¡ (XLM) of the main microprocessor is STOP or during the search mode, or
when Pin #¡ (UNLK) of DAT DSP (IC503) is “H” when RX PLL is in the unlocked state during digital
IN recording (Pin 9 of the main microprocessor (VCOEN) is “H”), “H” is input and the output of Pin
9 is set to “L”.
The flow of the signals in each mode is described in the following.
(1) When set to INPUT side during recording mode (See Fig. 5-21.)
Pin !§ of the main microprocessor outputs “L” and Pin !¶ outputs “H”. Switching between analog/
digital inputs is performed by the output from Pin !∞ of the main microprocessor , and the recording
signal is transmitted from the master DAT DSP to heads A-B. The analog input or digital IN
demodulation signal are directly output to the digital and analog outputs via the gate circuit of the
monitor selector (IC805) from Pin 9 of the selector (IC511).
digital inputs is performed by the output from Pin !∞ of the main microprocessor , and the recording
signal is transmitted from the master DAT DSP to heads A-B. The analog input or digital IN
demodulation signal are directly output to the digital and analog outputs via the gate circuit of the
monitor selector (IC805) from Pin 9 of the selector (IC511).
(2) When set to REPRO side during recording mode (See Fig. 5-22.)
The path of the recording signal is the same as that for the INPUT side in the recording mode (1).
During this time, Pin !¶ of the main microprocessor outputs “L”. As a result, the playback signals from
heads A’ and B’ for monitoring and slave DAT DSP (IC803) are transmitted to the digital and analog
outputs via the monitor selector (IC805). This is the simultaneous monitoring and playback (RAW)
function during recording.
During this time, Pin !¶ of the main microprocessor outputs “L”. As a result, the playback signals from
heads A’ and B’ for monitoring and slave DAT DSP (IC803) are transmitted to the digital and analog
outputs via the monitor selector (IC805). This is the simultaneous monitoring and playback (RAW)
function during recording.
(3) During playback mode (See Fig. 5-23.)
In this mode, Pin !§ of the main microprocessor outputs “H” and Pin !¶ outputs “H”. As a result, the
selector (IC511) is connected to the playback mode, and the playback signals from heads A and B and
master DAT DSP (IC503) are transmitted to the digital and analog outputs via the monitor selector
(IC805) from Pin 9 of the selector (IC511).
selector (IC511) is connected to the playback mode, and the playback signals from heads A and B and
master DAT DSP (IC503) are transmitted to the digital and analog outputs via the monitor selector
(IC805) from Pin 9 of the selector (IC511).
OUTPUT
Pin
9
0 n 9
!¡ n 9
!™ n 9
!£ n 9
!¡ n 9
!™ n 9
!£ n 9
L
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