Table of Contents
Advertisement
HOME
A. Signal Definition
Signal
Type
CI
Function display on
(Call Indicator)
the calling side
[Comments]
ANSam
V.8 procedure on the
(Modified
called side
Answer Tone)
[Comments]
Modulation mode etc.
CM
on the calling side
(Call Menu)
[Comments]
CJ
CM termination
[Comments]
JM
Display of common
(Joint Menu)
ability on both calling
and called sides
[Comments]
Signal Direction
Meaning
Call
Called
•
CI is a signal to carry Call Function.
•
The calling side send CI, CT (Call Tone - V25) or CNG.
•
CI transmission and detection are optional.
•
The ON minimum time (=3 Period) is of duration of three CI signals in the following format.
•
Essential for a called machine which supports the V8 procedure.
•
2100Hz sinewave is phase-inverted by 400 +/-25ms periods, then amplitude modulated by 15 +/-0.1
Hz sinewave
•
Average value of modulation factor (x)
•
Average transmission power compliant to V2
•
2100 +/- 200Hz external power is smaller than the average power by 24dB or more.
(300bps)
•
CM is a signal which carries Call Function, Modulation Modes, Protocols and GSTN access.
•
The first information category is Call Function.
•
Protocols and GSTN access category are added when the calling side has ability and when needed
to inform to a remote station.
(300bps)
•
START bit (0) and STOP bit (1) are added to 1 octet of all bit 0.
•
Signal format START bit
0
(300bps)
•
JM is a response signal to CM and of the same format as the received CM.
•
The fist information category is Call Function as same as CM.
•
Modulation Mode sets the common bit on calling and called sides and sends by the same octet as
received CM.
When there is no common ability, all bits are set to 0 and send by the same octet as received CM.
•
The minimum item No. is selected from the common bits to determine the actual Modulation Mode.
•
Protocol is added when it is included in received CM and needed to instruct.
•
GSTN access is added when it is included in received CM and needed to instruct.
•
Bit 6 is set to ON when needed to show ability. Bit 5 is set to the same one as received CM
Signal
Speed
V
2
( 1
) L
Start: after 0.4 seconds after line connection from ON
(300bps)
condition (in the following format)
Stop:
when 3 Period or more has passed after ANSam /
ANS is detected
When 0.2 seconds or more has passed after reception
0.8 +/- .01 < x < 1.2 +/- .01
Te (0.5 sec. ≤ Te ≤ 1 sec.) has passed after CI
Start:
V
2 .
( 1
) L
transmission stops
Stop:
When two or more JM are detected
V
2 .
( 1
) L
When CM is completed
b
0
b
1
b
2
b
3
b
4
b
5
b
6
b
7
STOP bit
0 0
0
0
0
0
0
0
Start: When two or more same CM are received
V
2 .
( 1
) H
Stop:
When CJ is received or receives a signal matching
the selected Modulation Mode from the calling side
7-11
Timing of Transmission
ON:
3period< T < 2sec
ON
OFF
OFF:
0.4sec < T < 2sec
1
Advertisement
Table of Contents
