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44.1 kHz (normal speed), 88.2 kHz (double speed)
The audio output level = 20 log ————— [dB]
Because, for example, the time that it would take to increase the attenuation level from "00H" to "EEH" using the 4 step-
up command would be as calculated below, this amount of time must be left before entering the next attenuation level
command:
* In order to prevent noise due to arithmetic overflow in the one-bit D/A converter, settings greater than EEH are
prohibited.
Mute Output Pin 51: MUTEL, Pin 57: MUTER
When the Mute control (MUTE –∞ dB: $03) is exerted, and once the data for each channel has been continuously at "0"
for a specified amount of time, then this output goes high. Afterwards, when data is again entered, this output
immediately goes low.
C2 Flag Output Pin 46: C2F
C2F is an 8-bit unit flag that indicates the data error status.
Digital OUT Output Circuit Pin 39: DOUT
This is the digital audio interface output pin. Its output is in EIAJ format. This signal is interpolated, and the signal is
output through the MUTE circuit. Because this output pin is equipped with an internal driver, it can drive a transformer
directly.
Code
$42
$43
$40
$41
$88
$8B
* The digital OUT pin can be fixed low by inputting the DOUT OFF command.
* Of the DOUT data, the UBIT data can be fixed at low by entering the UBIT OFF command.
* By entering the CDROM-XA command, the DOUT pin can be switched to CD-ROM data that is not subjected to
interpolation or to mute control. (When this is done, the audio output is put into mute mode.) The ROMXA-RST
command returns the DOUT pin to the audio data output mode which is subject to interpolation and mute control.
(When this is done, the audio output mute is released.)
Mute Control Circuit
Code
$01
$03
The sound level can be muted (MUTE –∞ dB) by the entry of the commands above. Because zero cross mute is used,
there is little noise during this operation. The zero cross determination is made in the range where the most significant 7
bits are all "1" or all "0." Because the MUTE–12 dB command ($02) that was found in the LC78620E and 78621E has
been deleted, the digital attenuator is used and ATT DATA = 60 ($3C) is set.
Start
ATT DATA
100H
238 level × 4 step-up
————————— ≈ 21.6 ms (approx.)
44.1 kHz (LRSY)
COMMAND
DOUT ON
DOUT OFF
UBIT ON
UBIT OFF
CDROM-XA
ROMXA-RST
COMMAND
MUTE 0 dB
MUTE –∞ dB
LC78626KE
RES = low
RES = low
Stop
No. 5995-22/34
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