Silicon Laboratories SI2493/57/34/15/04 - Manual (Page 229)

AN93
Rev. 1.3 229
8.2.1. Modem Specific Implementation Details
The DTMF transmitters and receivers are used to send and receive data. Voice mode operation documented in
chapter X is used to transmit and receive the tones.
A summary of the necessary tone transmission AT commands is shown in Table 144.
The procedure is as follows:
Modem Initialization: (host sends to modem ):
AT+FCLASS=8 (enters voice mode)
AT+VLS=15: (goes off hook and starts tone detection)
Send and receive tones example:
AT+VTS=[941,1336,10] Host commands modem to send DTMF digit 0.
0x10, 0x2F, 0x31, 0x32, 0x7E Modem responds with 5 characters as it receives two DTMF tones:
1 and 2. There are 2 preamble and 1 postamble characters
in this example.
Table 144. Ademco
®
Contact ID Protocol Tone Transmission AT Commands
DTMF Digit Low Tone (Hz) High Tone (Hz) Contact ID
Digit
Contact ID
Digit Value
AT Command
0 941 1336 0 10 AT+VTS=[941.1336. 10]
1 697 1209 1 1 AT+VTS=[697.1209. 10]
2 697 1336 2 2 AT+VTS=[697.1336. 10]
3 697 1477 3 3 AT+VTS=[697.1447. 10]
4 770 1209 4 4 AT+VTS=[770.1209. 10]
5 770 1336 5 5 AT+VTS=[770.1336. 10]
6 770 1477 6 6 AT+VTS=[770.1477. 10]
7 852 1209 7 7 AT+VTS=[852.1209. 10]
8 852 1336 8 8 AT+VTS=[852.1336. 10]
9 852 1477 9 9 AT+VTS=[852.1477. 10]
* 941 1209 B 11 AT+VTS=[941.1209. 10]
# 941 1477 C 12 AT+VTS=[941.1477. 10]
A 697 1633 D 13 AT+VTS=[697.1633. 10]
B 770 1633 E 14 AT+VTS=[770.1633. 10]
C 852 1633 F 15 AT+VTS=[852.1633. 10]
D 941 1633 not used N/A N/A
1400 ---- KISSOFF AT+VTS=[1400,0,85]