182 Voice API Programming Guide — June 2005
R2/MF Signaling
Table26. Meanings for R2/MF Group A Backward Signals Tone
Number Intel Define Meaning
1 SIGA_1 Send next digit (n+1)
2 SIGA_2 Send last but one digit (n-1)
3 SIGA_3 Address complete; change to Group B signals; no change back
4 SIGA_4 Congestion in the national network
5 SIGA_5 Send calling party’s category; change to Group II; can change back
6 SIGA_6 Address complete; charge; set up speech conditions
7 SIGA_7 Send last but two digit (n-2)
8 SIGA_8 Send last but three digit (n-3)
9 SIGA_9 Spare for national use
10 SIGA_0 Spare for national use
11 SIGA_11 Send country code indicator
12 SIGA_12 Send language or discriminating digit
13 SIGA_13 Send nature of circuit (satellite link only)
14 SIGA_14 Request for information on use of an echo suppressor
15 SIGA_15 Congestion in an international exchange or at its output