SI2457-D-FT Silicon Laboratories Inc, SI2457-D-FT Datasheet - Page 208

• 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
7.6.3.3. Record Local ICM
The Record Local ICM is identical to the Record OGM procedure provided in Table 129 on page 204. The main
difference is that one of the ADPCM formats is generally used and the PCM file is stored with the other ICM files
recorded from the PSTN.
7.6.3.4. Review ICM
The Review ICM is identical to the Review OGM procedure provided in Table 130 on page 206. The main
difference is that one of the ADPCM formats is generally used to conserve message space.
7.6.4. TAM PSTN
This system voice mode differs from the TAM Hands-Free and TAM Handset modes in that the modem is off-hook
and connected to the PSTN. Due to the paired nature of the +VGR and +VGT, the voice driver should maintain two
copies of each: one for RS232-to-Si3000 and another for RS232-to-DAA. See Figure 29 on page 188 for details.
7.6.4.1. Normal Answer – OGM Playback with ICM Record
208
Host to Modem Commands / Data
AT+VTS=[700,500,80]
AT+VTS=[700,500,80]
AT+VTS=[700,500,80]
AT+VGR=128
AT+VGT=128
AT+VSD=129
Table 131. TAM PSTN Normal Answer – OGM Playback with ICM Record
AT+VSM=4
AT:U199|8
NAME=JONES JENNIFER
Modem to Host Result
Codes/Data
DATE=0101
NMBR=102
TIME=0110
<DLE><R>
<DLE><X>
<DLE><R>
<DLE><R>
<DLE><.>
CIDM
Rev. 1.3
OK
OK
OK
OK
OK
OK
OK
OK
Ring Detection
Play local ring tone.
Receive Type I CID DLE complex report.
Ring Detection.
Play local ring tone.
Ring Detection. The voice driver will use a
rings-to-answer count. This example uses
three rings before answer.
Play local ring tone.
Mute the speaker so the OGM is not heard
locally. The user may remove this com-
mand to allow local review.
Set the DAA-to-RS232 receive gain regis-
ter (UBF) for TAM PSTN.
Set the RS232-to-DAA transmit gain regis-
ter (UB3) for TAM PSTN.
Set sensitivity level for ICM recording
silence detection.
Select G.711U -law PCM, 8-bit, 64 kbps
format. The voice driver will need to track
the OGM format with the OGM PCM file.
Local Modem Actions