11-10
Audio Decoder Module
The host can determine the decoder mode at any time by reading the
Audio Decoder Play Mode Status bits in Register 354 (
page 4-104). The
two bits are encoded identically to the play mode bits.
11.3.2 Audio Decoder Start/Stop
The Audio Decoder Start/Stop bit in Register 355 (
page 4-105) is used
to control both the selected audio decoder and its channel buffer read
pointer. When the Audio Decoder Start/Stop bit is set, the Audio Decoder
operates according to the play mode setting described in the previous
section. When the start/stop bit is cleared, the Audio Decoder is stopped
at the end of the current frame and the audio read pointer in the Audio
ES Channel Buffer is reset to the write pointer location. Any unread audio
data is lost to the decoder. The S/P DIF read pointer is not affected, so
the selected formatter can still run.
Once the decoder is stopped, the host should set the play mode bits to
Pause Mode. On restart, the host should rst set the start bit, wait for
some unread audio to accumulate in the channel buffer, and then change
the play mode bits from pause to play.
11.3.3 Audio Formatter Play Mode
The Audio Formatter bits in Register 356 (
page 4-106) control the play
mode of the selected formatter. There is no fast play or slow play mode
for the formatters, so codes 0b10 and 0b11 are reserved.
0b00 - Formatter is paused.
0b01 - Formatter is in normal play.
11.3.4 Audio Formatter Start/Stop
When the Audio Formatter Start/Stop bit is set, the selected formatter is
in the mode programmed into the play mode bits. When the start/stop bit
is cleared, the formatter is stopped and the S/P DIF read pointer is reset
to the Audio ES Channel Buffer write pointer. The audio read pointer is
not affected, so the selected audio decoder can still run.
Once the formatter is stopped, the host should set the play mode bits to
pause mode. On restart, the host should rst set the start bit, wait for
some unread audio to accumulate in the channel buffer, and then change
the play mode bits from pause to play.