January 2001 © TOSHIBA TEC
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GD-1060 DIALING AND COMMUNICATION PROCEDURE
b-5)
Control channel
The conventional T.30 procedure is performed. The transmission rate is 1200 bps.
• Transmitter
• Receiver
Note: In the control channel, the frequency of a signal to be sent is different between transmission and
reception. The signal echoed back has never been misidentified as a signal sent from the other
unit. Therefore, this channel is not influenced by a signal echoed back.
Signal name
Flag
Non-standard fa-
cilities setting
Transmitting
Subscriber ID
Digital Command
Signal
——
Abbreviation
flags
NSS
TSI
DCS
1
Meaning
It maintains synchronization.
It receives an NSF sent from the
receiver. It selects the available
mode according to the received
NSF, then specifies the mode for
reception.
It indicates the telephone number
of the transmitter.
It specifies the mode that can be
communicated.
It declares to switch to the high-
speed procedure.
Remark
7E (H)
“1” is sent continuously.
Signal name
Non-Standard
Facilities
Called Subscriber
ID
Digital
Identification
Signal
Flag
Confirmation to
receive
Abbreviation
NSF
CSI
DIS
flags
CFR
Meaning
It indicates the facilities which are
not recommended by ITU-T, ab-
breviated user’s name, and
manufacturer code.
It indicates the telephone number
of the receiver.
It indicates the standard facili-
ties recommended by ITU-T.
It maintains synchronization.
It indicates that the training of the
modem is complete, and the re-
ceiver is ready to receive the im-
age signal.
Remark
7E (H)