1. Greeting message recording (Put a MIC into dial-up line RJ11 jack) DTE DCE comments ------------- ----------- --------------------- AT+FCLASS=8 ---> Switch to voice mode <--- OK AT+VSM=? ---> 1;CELP;1;0;(9600) 2;ADPCM;2;0;(9600) 3;ADPCM;3;0;(9600) 30;ADPCM;3;0;(9600) 4;ADPCM;4;0;(9600) <--- OK AT+VSM=1 ---> Select CELP compression method <--- OK AT+VLS=8 ---> Activate external MIC on Line Jack <--- VCON AT+VRX ---> Start to record <--- CONNECT <--- AT ---> Stop recording <--- <--- <--- VCON Return to commnad state AT+VLS=0 ----> Deactivate external MIC on Line Jack <--- OK AT+FCLASS=0 Return to data mode <--- OK
2. Voice file playing via internal speaker DTE DCE comments ----------- ----------------- ------------------- AT+FCLASS=8 ---> Switch to voice mode <--- OK AT+VSM=? ---> 1;CELP;1;0;(9600) 2;ADPCM;2;0;(9600) 3;ADPCM;3;0;(9600) 30;ADPCM;3;0;(9600) 4;ADPCM;4;0;(9600) <--- OK AT+VSM=1 ---> Select CELP compression method <--- OK AT+VLS=16 ---> Activate internal speaker <--- VCON AT+VTX ---> Start to play <--- CONNECT ---> ---> <--- VCON Return to commnad state AT+VLS=0 ---> Deactivate internal speaker <--- OK AT+FCLASS=0 Return to data mode <--- OK
3. Voice file playing via line DTE DCE comments ----------- -------------- -------------------- AT+FCLASS=8 ---> Switch to voice mode <--- OK AT+VSM=? ---> 1;CELP;1;0;(9600) 2;ADPCM;2;0;(9600) 3;ADPCM;3;0;(9600) 30;ADPCM;3;0;(9600) 4;ADPCM;4;0;(9600) <--- OK AT+VSM=1 ---> Select CELP compression method <--- OK AT+VLS=2 ---> Connect to line <--- VCON AT+VTX ---> Start to play <--- CONNECT ---> ---> <--- VCON Return to commnad state AT+VLS=0 ---> Deactivate line connection <--- OK AT+FCLASS=0 Return to data mode <--- OK
4. Answering machine (Voice call) DTE DCE comments ----------- -------------- ------------------- AT+FCLASS=8 ---> Switch to voice mode <--- OK AT+VSM=? ---> 1;CELP;1;0;(9600) 2;ADPCM;2;0;(9600) 3;ADPCM;3;0;(9600) 30;ADPCM;3;0;(9600) 4;ADPCM;4;0;(9600) <--- OK AT+VSM=1 ---> Select CELP compression method <--- OK AT+VLS=2 ---> Connect to line <--- VCON AT+VTX ---> Start to play greeting message <--- CONNECT ---> ---> <--- VCON return to commnad state AT+VRX ---> Start to record <--- CONNECT <--- <--- b DCE detects busy tone or or q long period of quiet AT ----> Stop recording <--- DCE deliver remaining data <--- <--- VCON Return to commnad state AT+VLS=0 ---> Deactivate line connection <--- OK AT+FCLASS=0 Return to data mode <--- OK
5. Answering machine (Fax call) DTE DCE comments ----------- -------------- ------------------ AT+FCLASS=8 ---> Switch to voice mode <--- OK AT+VSM=? ---> 1;CELP;1;0;(9600) 2;ADPCM;2;0;(9600) 3;ADPCM;3;0;(9600) 30;ADPCM;3;0;(9600) 4;ADPCM;4;0;(9600) <--- OK AT+VSM=1 ---> Select CELP compression method <--- OK AT+VLS=2 ---> Connect to line <--- VCON AT+VTX ---> Start to play greeting message <--- CONNECT ---> <--- c T.30 fax calling tone detected or or 5 DTMF digit '5' detected ---> ---> <--- VCON Return to commnad state AT+FCLASS=2 ---> Try to handshake Fax mode <--- OK ATA ---> Switch to fax mode and answer fax call . . .
6. Answering machine (Data call) DTE DCE comments ----------- ------------- -------------------- AT+FCLASS=8 ---> Switch to voice mode <--- OK AT+VSM=? ---> 1;CELP;1;0;(9600) 2;ADPCM;2;0;(9600) 3;ADPCM;3;0;(9600) 30;ADPCM;3;0;(9600) 4;ADPCM;4;0;(9600) <--- OK AT+VSM=1 ---> Select CELP compression method <--- OK AT+VLS=2 ---> Connect to line <--- VCON AT+VTX ---> Start to play greeting message <--- CONNECT ---> ---> <--- VCON Return to command state AT+VRX ---> Start to record <--- CONNECT <--- <--- s DCE detects silence AT ----> Stop recording <--- DCE deliver remaining data <--- <--- VCON return to command state (DTE delete this silence file) AT+FCLASS=0 ---> <--- OK ATA ---> Try to handshake data mode Switch to data mode and answer data call . . .

Voice data compression.
ZyXEL Advanced Voice Capability.