AN93

7.4. Initialization

The following sequence is used after power up or hardware reset to prepare the modem for voice operations. This procedure occurs in the Initialize state presented in Figure 31. After initialization, the system will be in the TAM Hands-Free mode, which is discussed in "7.3.3.1. TAM Hands-Free".

Table 119. Initialization Sequence

 

Modem to

 

Host to Modem Commands

Host Result

Local Modem Actions

 

Codes

 

 

 

 

ATZ

OK

Reset. The Si3000 is not reset by this

command.

 

 

 

 

 

ATE0+FCLASS = 0

OK

Disable local AT command echo and

enter data mode, which is necessary for

 

 

patch loading.

AT+IPR = 115200

OK

Disable autobaud and set rate to

115,200 bps.

 

 

 

 

 

[ Apply Patch Commands ]

OK

Apply the modem patch commands.

 

 

 

AT:U199A

OK

Mute the microphone and speaker

paths to the codec.

 

 

 

 

 

 

 

Disable local AT command echo and

ATE0+FCLASS = 8

OK

enter voice mode. Limited V.253 event

reporting enabled with default setting of

 

 

 

 

+VLS=0.

 

 

 

AT+VLS = 0

OK

Disable voice mode. Used as a transi-

tion point between non-zero +VLS voice

 

 

modes.

 

 

 

AT+VLS = 14

OK

Setup on-hook TAM voice mode. See

Table 117 on page 190 for details.

 

 

 

 

 

AT*Y254:W591

OK

Enable the SSI interface to the Si3000.

 

 

 

AT*Y0

OK

Exit the AT*Y command mode.

 

 

 

AT+VCDT = 1

OK

Enable always-on Type I Caller ID.

 

 

 

AT+VCID = 1

OK

Enable formatted Caller ID.

 

 

 

AT+VSD = 129

OK

Set silence detection sensitivity level.

 

 

 

AT+PCW = 0

OK

Enable Type II Caller ID reporting.

 

 

 

AT:U0B1,0500

OK

Set Si3000-to-DAA transmit gain.

 

 

 

AT:U0B5,0200

OK

Set DAA-to-Si3000 receive gain.

 

 

 

AT:U0B6,0100

OK

Set Sidetone gain.

 

 

 

AT:U0B9,0300

OK

Set VTS-to-Si3000 transmit gain.

 

 

 

AT:U0B4,0600

OK

Set VTS-to-DAA transmit gain.

 

 

 

 

 

 

194

Rev. 1.3

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Silicon Laboratories SI2493/57/34/15/04, SI2494/39 manual Initialization Sequence