The concept of address signaling in R2 is slightly different from that used in the other CAS systems previously discussed. In the case of R2, the exchanges are considered registers, and the signaling between these exchanges is called inter-register signaling. Inter-register signaling uses forward and backward in-band MF signals to transfer called and calling party numbers as well as the calling party category.

In this case, signaling is compelled because the registers in the outgoing and incoming exchanges hold the signal until an acknowledgment is received. The signals consist of two voice-band frequencies and are listed in Table 3-10.

Table 3-10. CCITT-R2 and National R2 Inter-Register Signal Frequencies | |||

Signal |
Forward Frequency in Hz |
Backward Frequency in Hz | |

Dig |
t 1 |
1380 and 1500 |
1140 and 1020 |

Dig |
t 2 |
1380 and 1620 |
1140 and 900 |

Dig |
t 3 |
1500 and 1620 |
1020 and 900 |

Dig |
t 4 |
1380 and 1740 |
1140 and 780 |

Dig |
t 5 |
1500 and 1740 |
1020 and 780 |

Dig |
t 6 |
1620 and 1740 |
900 and 780 |

Dig |
t 7 |
1380 and 1860 |
1140 and 660 |

Dig |
t 8 |
1500 and 1860 |
1020 and 660 |

Dig |
t 9 |
1620 and 1860 |
900 and 660 |

Dig |
t 0 |
1740 and 1860 |
780 and 660 |

Not used |
1380 and 1980 |
1140 and 540 | |

Not used |
1500 and 1980 |
1020 and 540 | |

Not used |
1620 and 1980 |
900 and 540 | |

Not used |
1740 and 1980 |
780 and 540 | |

End of # |
1860 and 1980 |
660 and 540 |

Was this article helpful?

## Post a comment