Canon MultiPASS C530 Service Manual page 124

c) Examples of sequences
The signals in the shaded areas are important in the protocol.
c-1) Late start
Since the receiver cannot detect the CM signal while sending the ANSam signal, it sends the DIS
signal containing the "V.8 protocol" declaration. The transmitter sends the CI signal to request the
receiver to send the ANSam signal again to move to V.8 protocol.
(DIS cannot be detected.)
MultiPASS C530/C560 Chapter 2: Technical Reference
TX RX
Connected to the line
ANSam
NSF
CSI
DIS
CNG
NSF
CSI
DIS
CI
ANSam
CM
JM
CJ
Figure 2-26 Late Start
2-45