Canon PowerShot G3, Error Code List

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Appendix
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4.3 Major Signals Used for Channel D Layer 2
SABME (Set Asynchronous Balanced Mode Extended)
It is the first signal transmitted when setting layer 2. However, the called side sends SABME
after it has received SETUP form the network.
UA (Unnumbered Acknowledge)
It is a signal used to acknowledge response to SABME or DISC.
DISC (Disconnect)
It is used to indicate disconnection of layer 2.
4.4 Major Signals Used for Channel D Layer 3
SETUP (Setup)
It is used to request the calling settings. The calling side sets layer 2, and first sends it to
set layer 3. The called side, on the other hand, first receives it from the network when a
call is set (before the connection procedure for layer 2). SETUP communicates telephone
number information, communication terminal attributes, and others.
CALL PROC (Call Proceeding)
It is received from the network when SETUP of the calling side is accepted by the net-
work.
ALERT (Alerting)
It is a signal used while a call is being made. The called side transmits it when the called
terminal is being called, while the calling side receives it when the terminal of the other
party is being called.
CONN (Connect)
It is used as a response. The called side sends it in response to SETUP it has received,
while the calling side receives it when the terminal of the other party has responded.
CONN ACK (Connect Acknowledge)
It is a signal used to acknowledge response to CONN. The calling side sends it in re-
sponse to CONN it has received, white the called side receives it from the network in
response to CONN it has transmitted.
DISC (Disconnect)
It is a signal used to request disconnection of layer 3. To disconnect layer 3, the signal is
sent to the network or arrives from the network.
REL (Release)
It is used to accept a request for disconnection and to indicate that layer 3 has been
released. The machine that has received DISC sends it to the network, thus releasing layer
3, while the machine that has sent DISC receives it from the network.
REL COMP (Release Complete)
It is used to indicate that the machine requesting disconnection has also released layer 3.
It is sent by the machine that has received REL to the network, thereby releasing layer 3.
The machine that has sent REL receives it from the network to find out that the layer has
been released.