
No. 5342-21/34
LC78631E
12. Interpolation circuit
Outputting incorrect audio data that could not be corrected by the error detection and correction circuit would result
in loud noises being output. To minimize this noise, the LC78631E replaces incorrect data with linearly interpolated
data based on the correct data on both sides of the incorrect data.
If incorrect data continues for two or more consecutive values, the LC78631E holds the previous correct data value
and then applies average value interpolation to the previous incorrect value of the next correct data value to calculate
the value that precedes the next correct value.
13. Bilingual function
Following a reset or when a stereo ($28) command has been issued, the left and right channel data is output to the
left and right channels respectively.
When an Lch set ($29) command is issued, the left and right channels both output the left channel data.
When an Rch set ($2A) command is issued, the left and right channels both output the right channel data.
14. De-emphasis; Pin 32: EMPH
The pre-emphasis on/off bit in the subcode Q control information is output from the EMPH pin. When this pin is
high, the LC78631E internal de-emphasis circuit operates and the digital filter and the D/A converter output de-
emphasized data.
In antishock mode, the P2 pin input is output without change from the EMPH pin and the EMPH pin becomes simply
a monitor for the de-emphasis filter on/off state.
15. Digital attenuator
Attenuation can be applied to the left and right channel audio data independently by issuing two-byte commands.
Alternatively, both channels can be attenuated at the same time using the $81 command.
Code
Command
RES = low
$28
STO CONT
q
$29
Lch CONT
$2A
Rch CONT
Code
Command
RES = low
$81
Lch, Rch ATT SET
$82
Lch ATT SET
$83
Rch ATT SET