GD-1060 DIALING AND COMMUNICATION PROCEDURE
4 - 12
January 2001 © TOSHIBA TEC
4.2.2.4 Training
The training signal involves a pre-determined picture signal which is used to check the capability of the
phone line to reliably support facsimile traffic.
•
Training signal
The training signal is transmitted following DCS with the modem speed to be selected by DCS. At the
receiving station, the automatic equalizer is adjusted by the training signal.
•
Format of the training signal
<14.4 K bps, 12 K bps>
<9600 bps, 7200 bps>
<4800 bps, 2400 bps>
•
TCF signal
When training is not performed correctly, an error may occur in the picture signal. The Tx station
transmits a TCF signal and checks if any error occurs in picture data before the picture data commu-
nication to follow. When the Rx station detects an error in the TCF signal, the Rx station sends an FTT
signal to the Tx station and request for re-training. When normal, a CFR signal is sent instead.
The modem speed of TCF signal is the same as the training signal, and it transmits all zeros for 1.5
seconds.
Alterations
of
ABAB
Equalizer
Condition
Pattern
Rate
Pattern
Scrambled Binary
Data "1"
TCF
106 msec.
1240 msec.
27 msec.
20 msec.
1393 msec.
Segment 1
Segment 2
Segment 4
Segment 3
Segment 4
20 msec.
50 msec. + 160 msec.
20 msec.
V29
No-signal
Repeating two state signals
(Binary)
Scrambled
Data "1"
(Hexa or Octal)
TCF
Segment 1
Segment 2, Segment 3
253 msec.
Segment 1
4800 bps: 923 msec.
2400 bps: 1158 msec.
V27ter
TCF
Non-
modulated
Carrier
Continuous 180°
Phase Inversion
(Binary)
0° to 180°
two-phase pattern
(Binary)
Scrambled
Data "1"
(Hexa or Octal)
No-signal
Segment 4
Segment 5
Segment 2
Segment 3