X25AM Programming Manual

X3PAD Interface
X25AM Programming Manual—527201-001
4-8
Establishing a Call
The Guardian CONTROL 11 procedure is used by a process to wait for a call. X3PAD
always has a CONTROL 11 pending if no call has been established so that it can
receive a call. The CALL command is used to initiate a call.
CALL [ address ]
A call can be cleared at any time, with or without intervention by the terminal user.
When a call is cleared, a message is written to the OUT file in the following form:
CALL CLEARED.
clear-indication.
Table 4-6 lists the clear-indication values, or messages.
In addition to the information given by the call clearing message, diagnostic data can
also be received from the network. This information is written to the OUT file in the
form:
DIAGNOSTIC OCTET #n = xxx
where
#n is a sequential octet number and xxx is a decimal integer in the range of 0-255.
The diagnostic octet values are defined in CCITT Recommendation X.25. They are
discussed in more detail in the ISO 8208 standards documentation.
Table 4-6. Clear-Indication Values
Description
THAT NUMBER IS NOT IN SERVICE.
THAT NUMBER IS BUSY. TRY AGAIN LATER.
THAT NUMBER WILL NOT ACCEPT REVERSE-CHARGE CALLS.
THAT NUMBER WILL NOT ACCEPT "FAST SELECT" CALLS.
THE NETWORK IS BUSY. TRY AGAIN LATER.
THE NETWORK WILL NOT ALLOW YOU TO CALL THAT NUMBER.
A FACILITY WHICH WAS REQUESTED IS NOT AVAILABLE.
BY THE CALLED PARTY.
BY THE CALLED PARTY, USING 'INVITATION TO CLEAR'.
LOCAL PROCEDURE ERROR.
REMOTE PROCEDURE ERROR.