Envoy ACP/XF Application Programming Manual

Normal Response Mode (NRM) Protocols
EnvoyACP/XF Application Programming Manual–132179
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SDLC Multipoint Supervisor
!the AWAITIO call should complete with CCG (indicating that
!the received frame generated a nonzero MCW)
AWAITIO fnum
If <> do error handling
For the READ operation, there are two points at which a condition code is returned:
•
When the actual call is issued.
•
When the associated operation is completed by the AWAITIO call.
When the call is issued, a CCG or CCL indicates that the call was unacceptable to either
Guardian or to EnvoyACP/XF. Your error-handling procedure then should call
FILEINFO to obtain a more specific error code.
If the request is accepted, the condition code returned for the AWAITIO call tells you
whether the operation was performed properly.
If you want the point-to-point secondary station to perform two-way, simultaneous
communication over full-duplex, nonswitched, line facilities, use the code sequence
above except issue the SETMODE call set as follows:
CALL SETMODE (line^fnum,16,%410);
This SETMODE call ensures that the system-generation parameters are set as follows:
•
Point-to-point secondary station
•
Full-duplex line facilities (two-way, simultaneous operation)
•
Nonswitched lines
•
Use of REJ supervisory frame ALLOWED
•
RS-232C line interface
For switched line facilities, include a CONTROL 17 call after the SETMODE, but
before the first READ. The CONTROL 17 sends a Data Terminal Ready signal to the
modem. For the AWAITIO call for the CONTROL 17 request, include a time limit long
enough to allow the operator to make the connection or specify no time limit (wait
indefinitely).
SDLC Multipoint Supervisor
The example below shows how to initiate an SDLC link for a multipoint supervisor that
performs two-way, alternate communication over half-duplex, nonswitched, line
facilities.
In this example, the line name is $SUPR0.
!Open the line "SUPR0"
OPEN SUPR0,fnum,%36
If <> do error handling
!The following SETMODE call ensures that the crucial system
!generation parameters are set as follows: