![](http://datasheet.mmic.net.cn/50000/92HD89E1X5NDGXYYX8_datasheet_1923441/92HD89E1X5NDGXYYX8_19.png)
19
V1.0 04/10
2009 INTEGRATED DEVICE TECHNOLOGY, INC.
92HD89E
Ten channel HD Audio codec optimized for low power
In general, the SPDIF input block does not alter the data received. However, it is sometimes neces-
sary to alter the data when the converter widget settings do not match the stream format. The follow-
ing table outlines a few cases and the expected behavior.
Port presence detect for SPDIF_IN operates differently from other ports. Once the PLL has locked
and valid framing (no errors) has been detected, then the port presence detect bit is set. In D3, and
D3 without a clock, it is not possible to check for proper framing. Monitoring of activity (rising and fall-
ing edges) is sufficient to verify a change in connectivity in D3. If no clock is present, then the internal
oscillator is used until a clock is restored. When the HD Audio bus is in a low power state (reset
asserted and clock stopped) the CODEC will generate a Power State Change Request when a
change in SPDIF_IN port connectivity is sensed and then generate an unsolicited response after the
HD Audio link has been brought out of a low power state and the device has been enumerated. Per
ECR015-B, this will take less than 10mS.
2.3.
Analog Mixer
The mixer supports independent gain (-34.5 to +12dB in 1.5dB steps) on each input as well as inde-
pendent mutes on each input. The following inputs are available: The output of the mixer may be
sent to the ADC where the ADC record gain can adjust the volume. If the output of the mixer is sent
to an analog port, then a separate volume control is provided to adjust the output volume. This mixer
output volume control supports a gain range of -46.5dB to 0dB in 1.5dB steps. (Selecting -46.5dB
will automatically mute the output.)
inMux0
inMux1
inMux2
inMux3
CD In
Conflict
Behavior
Resolution
Converter widget rate does not
equal the stream rate
Although the SPDIF input block is designed
to handle inputs slightly above or below the
programmed rate, samples may be lost if
the input rate is much higher than the rate
programmed into the converter widget.
Program the converter widget with the
same rate as indicated by the input stream.
Converter widget programmed
for a word length less than the
word length provided by the
input stream
If the input stream indicates non PCM data,
the data will be truncated to the requested
word length. If LPCM data is indicated in the
input stream, the CODEC will round the
received data to the requested length.1
1.Rounding may be disabled by setting the disable bit (AFG vendor specific verb -see widget list) or setting the
SPDIF_IN converter widget Frmt StrmType field to 1 (non-PCM)
Program the converter widget with the word
length indicated in the input stream.
Converter widget programmed
with a word length greater than
the word length provided by
the input stream.
Regardless of content, 24 bits per channel
of data will be transferred from the SPDIF
input stream to the HD Audio bus interface.
Truncation or rounding to the requested
word length will be handled as described as
above. Any non-zero data in the incoming
stream will cause problems.
Program the converter widget with the word
length indicated in the input stream.
Although not recommended, application or
driver software may program the converter
widget with a word length of 24 bits,
truncate the input to the word length
indicated by the input stream, then right
extend the data using 0s to the desired
word length.
Table 8. SPDIF Behavior