Rockwell RCV144ACx, Command Reference Manual

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AT Command Reference Manual
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Table 7-13. Originate a Call, Send Answerer a Message
DTE to Modem Modem to DTE Description and Interpretation
#CLS=8 Configure the modem for Voice Mode (still ADPCM).
OK The modem agrees, and is now set up for voice.
#BDR=16 The DTE knows that compression requires a 38,400 bps speed, so it forces this as the
new speed.
OK This OK message is sent at 2400 bps, but the modem then switches to 38,400 bps.
#VLS=0 This ensures that the telephone line is selected.
OK The modem agrees.
#VRA=45 The DTE allows 4.5 seconds for ringback to stop before assuming that the modem
thinks that the remote has answered.
OK The modem agrees with the DTE's assumption.
DT6807 The DTE makes a telephone call, and the modem dials and goes through call
progress. BUSY or NO DIALTONE can be detected, but in this example, the modem
gets ringback.
VCON This message is sent 4.5 seconds after the third ringback cadence is detected by the
modem. The modem is in effect assuming that the remote telephone was answered on
the third ring because no fourth ringback was detected before the #VRA time-out. The
modem enters Online Voice Command Mode, and DTMF and answer tone detection is
enabled. (Note that during this period, the modem might have detected answer tone
from a data modem. In this case, the appropriate <DLE> shielded code has to be sent
prompting the DTE to pursue a data handshake.)
#VTX The DTE has a message to send.
CONNECT The modem says: “send it.”
<Data> The DTE sends the message: “Hi Dave. Your mother called.”
<DLE><ETX> Procedure complete.
VCON DTMF still active.
H The DTE has completed its forwarding task.