SI2457-D-FT Silicon Laboratories Inc, SI2457-D-FT Datasheet - Page 186

• Manufacturer Part Number: SI2457-D-FT
• Description: IC ISOMODEM SYSTEM-SIDE 24TSSOP
• Manufacturer: Silicon Laboratories Inc

Specifications of SI2457-D-FT

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

AN93
The SMUTE bit (U199 [1]) mutes the speaker output audio path. The bit should be cleared for normal
speakerphone operation. For recording during hands-free TAM, the bit should be set to mute the speaker output.
The MMUTE bit (U199 [3]) mutes the microphone input audio path. The bit should be cleared for the normal
speakerphone operation. For message review during hands-free TAM, the bit should be set to mute the
microphone.
Bit SPCAL (U199 [2]) in U199 must be set for speakerphone’s calibration and cleared for normal speakerphone
operation.
Bit fields SPKREF and MICREF in U19E contain the speakerphone’s speaker and microphone levels during
speakerphone calibration.
186
U19E AECREF
U199 VPCTRL
Reg
Bit
8
7
6
3
2
1
Name
SSP_LOCTALK
SSP_FLAG
SSP_PTT
MMUTE
SMUTE
SPCAL
Name
15-9
Bits
SSP_LOCTALK SSP_PTT SSP_FLAG
SPKREF
Table 115.
Bit8
Function
1 = Local talker enabled
0 = Remote talker enabled
Toggled by <DLE><0x27>
1 = Manually switch between near/far talker (push-to-talk mode)
0 = Automatically switch based on signal levels
Toggled by <DLE><0x26>
1 = Enable SSP mode
0 = Disable SSP mode
Toggled by <DLE><0x25>
1 = Mute speaker of speakerphone or handset
0 = Unmute speaker
1 = AEC speaker / microphone calibration
0 = Normal mode
1 = Mute local talker
0 = Unmute local talker
Table 116.
U199 and U19E Register Bit Maps
Bit7
U199 Bit Definitions
Rev. 1.3
Bit6
Bits
4-5
MICREF
MMUTE SPCAL SMUTE
Bit 3
Bit 2
Bit 1
Bit 0