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82801AA and 82801AB Datasheet
5-113
Functional Description
For multiple sample rate input, the tag bit for each input slot indicates whether valid data is present
or not.
NOTE:
*Slot 3 Request and Slot 4 Request bits must be the same value (i.e., set or cleared in tandem).
As shown in
Table 5-83
, slot 1 delivers codec control register read address and multiple sample rate
slot request flags for all output slots of the controller. When a slot request bit is set by the codec, the
controller returns data in that slot in the next output frame. Slot request bits for slots 3 and 4 are
always set or cleared in tandem (i.e., both are set or cleared).
When set to 1, the input slot 1 tag bit only pertains to Status Address Port data from a previous
read. SLOTREQ bits are always valid independent of the slot 1 tag bit.
Input Slot 2: Status Data Port
The status data port receives 16-bit control register read data.
Bit [19:4]: Control Register Read Data
Bit [3:0]:
Reserved.
Input Slot 3: PCM Record Left Channel
Input slot 3 is the left channel input of the codec. The ICH supports 16-bit sample resolution.
Samples transmitted to the ICH must be in left/right channel order.
Input Slot 4: PCM Record Right Channel
Input slot 4 is the right channel input of the codec. The ICH supports 16-bit sample resolution.
Samples transmitted to the ICH must be in left/right channel order.
Input Slot 5: Modem Line
Input slot 5 contains MSB justified modem data. The ICH supports 16-bit sample resolution.
Input Slot 6: Optional Dedicated Microphone Record Data
Input slot 6 is a third PCM system input channel available for dedicated use by a microphone. This
input channel supplements a true stereo output that enables a more precise echo cancellation
algorithm for speakerphone applications. The ICH supports 16-bit resolution for slot 6 input.
Table 5-83. Input Slot 1 Bit Definitions
Bit
Description
19
Reserved (Set to zero)
18:12
Control Register Index (Stuffed with zeros if tagged invalid)
11
Slot 3 Request: PCM Left Channel*
10
Slot 4 Request: PCM Right Channel*
9
Slot 5 Request: Modem Line 1
8:2
Slot Request 6-12: Not Implemented
1:0
Reserved (Stuffed with zeros)