WM9705 Datasheet, PDF (35/55 Pages) Wolfson Microelectronics plc – Multimedia AC97 CODEC with Integrated Touch Screen Controller

WM9705
DATA BIT FUNCTION
VRA
Variable rate audio support
DRA
Double rate audio support
SPDIF
SPDIF transmitter supported
VRM
Variable rate Mic ADC support
DSA0
DAC slot mapping control
DSA1
DAC slot mapping control
CDAC
Centre DAC support
SDAC
Surround DAC support
LDAC
LFE DAC support
AMAP
Slot mapping support for Codec ID
REV0
Revision number
REV1
Revision number
ID0
Codec configuration – pin 45 value
ID1
Codec configuration – fixed in WM9705
Table 16 Extended Audio ID Register
Production Data
VALUE
1
0
‘1’ = supported
0
See table below
See table below
0
0
0
1
1
0
0 (Inverse of level at pin 45)
0
DSA1, DSA0
DAC SLOT MAPPING
00
Slots 3 and 4
01
Slots 7 and 8
10
Slots 6 and 9
11
Slots 10 and 11
Table 17 DAC Slot Mapping
DAC slot mapping to slots 7 and 8 or slots 6 and 9 cannot be used in variable rate mode (VRA=1)
for sample rates other than 48kHz.
REGISTER 2AH – EXTENDED AUDIO STATUS AND CONTROL REGISTER
The Extended Audio Status and Control Register is a read/write register that provides status and
control of the extended audio features. Note that SPDIF slot mapping default varies according to
codec pin configuration. See Table 2.
DATA BIT FUNCTION
READ/WRITE
VRA
Enables variable rate audio mode
Read/write
SPDIF
SPDIF transmitter enable
Read/write
SPSA0
SPDIF slot assignment
Read/write
SPSA1
SPDIF slot assignment
Read/write
SPCV
SPDIF validity bit
Read
Table 18 Extended Audio Status and Control Register
SPSA0, SPSA1 SPDIF SLOT MAPPING
00
Slots 3 and 4
01
Slots 7 and 8
10
Slots 6 and 9
11
Slots 10 and 11
Table 19 SPDIF Slot Mapping
REGISTER 2Ch AND 32h – AUDIO SAMPLE RATE CONTROL REGISTERS
These registers are read/write registers that are written to, to select alternative sample rates for
the audio PCM converters. Default is the 48ks/s rate. Note that only Revision 2.2 recommended
rates are supported by the WM9705, selection of any other unsupported rates will cause the rate
to default to the nearest supported rate, and the supported rate value to be latched and so read
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PD Rev 4.0 December 2003
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