AN93
Rev. 1.4
215
7.6.2.1. Record OGM
The Si3000-to-RS232 gain register UC0 in the ISOmodem can be used to adjust the voice stream gain. Use the
+VGR command to adjust the UC0 value in command mode. It is best to maintain two versions of +VGR: one for
Si3000-to-RS232 and another for DAA-to-RS232.
Table 141. TAM Hands-Free Record OGM
Host to Modem Commands /
Data
Modem to Host Result
Codes/Data
Local Modem Actions
AT+VGR=128
OK
Set the Si3000-to-RS232 receive gain (UC0) for TAM
Hands-Free.
AT:U0B1,0500
OK
Restore Si3000-to-DAA transmit gain path to allow
voice samples to reach FDV block for silence detection.
This allows the driver to automatically end OGM
recording.
AT+VSD=129
OK
Set sensitivity level for OGM recording silence detec-
tion.
AT+VSM=4
OK
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.
AT+VTS=[1000,0,100]
OK
Play user record tone prompt.
AT:U199|8
OK
Mute speaker to avoid echo (speakerphone algorithm
off).
AT:U199&FFFD
OK
Enable microphone for OGM recording.
AT+VRX
CONNECT
Trigger receive operation. The first byte after the new-
line character following the CONNECT message will be
the first data stream byte.
[Voice Stream]
Receive OGM voice stream. During voice stream cap-
ture, the user can adjust the UC0 value via the
<DLE><u> and <DLE><d> commands. The host voice
driver will need track the number of adjustments and
update the +VGR value for future use.
<DLE><!>
<DLE><ETX>
OK
Terminate the receive operation. The modem will
respond with <DLE><ETX> to mark the end of the data
stream. The OK denotes the return to command mode.
AT:U0B1,0
OK
Disable Si3000-to-DAA transmit gain path. This
ensures codec tones are not sent to the FDV and
DTMF.
AT:U199|2
OK
Mute the microphone.
AT:U199&FFF7
OK
Enable speaker for local ring tone/alert tones.
Summary of Contents for Si2404
Page 2: ...AN93 2 Rev 1 4 ...
Page 200: ...AN93 200 Rev 1 4 Figure 31 TAM Handset and Speakerphone Voice Paths ...
Page 201: ...AN93 Rev 1 4 201 Figure 32 Si3000 Codec Gain and Signal Selection Options ...
Page 290: ...AN93 290 Rev 1 4 Figure 57 256 Band Spectral Display Figure 58 2048 Band Spectral Display ...
Page 305: ...AN93 Rev 1 4 305 Figure 76 Parallel or SPI Port Interrupt Service Flowchart ...