Envoy ACP/XF Application Programming Manual

Normal Response Mode (NRM) Protocols
EnvoyACP/XF Application Programming Manual–132179
3-46
SDLC and ADCCP-NRM Nonswitched Multipoint
Operation
SDLC and ADCCP-NRM Nonswitched Multipoint Operation
The example below shows how to use file-system procedures and error returns in an
EnvoyACP/XF, centralized, multipoint configuration using two-way, alternate,
communication over half-duplex, nonswitched, line facilities. For simplicity, only the
activities of the supervisor process and one tributary process are given. The tributary
process controls one SDLC port but responds to two station addresses.
The configured device name of the primary station line is $SUPR; the configured device
name of the tributary station line is $TRB1. After opening their respective lines, each
application process calls the SETMODE procedure to ensure that the required line
characteristics are properly defined.
SUPERVISOR TRIBUTARY
INT lnr [0:11] := ["$SUPR ", INT lnr [0:11] := ["$TRB1 ",
9 * [" "]], pnum; 9 * [" "]], snum;
. .
. .
CALL OPEN (lnr,pnum,14); CALL OPEN (lnr,snum,14);
CALL SETMODE (pnum,16,%1002); CALL SETMODE (snum,17,128,
%40502);
CALL SETMODE (snum,16,3);
The lines are opened for exclusive read or write access and for nowait I/O with a
maximum of 14 concurrent outstanding requests. In the supervisor, the SETMODE 16
call defines the station as a multipoint supervisor, sets the station to accept all addresses,
and defines the link as half-duplex. In the tributary, the SETMODE 17 call defines the
maximum frame size (128 words) and passes the addresses A and B to EnvoyACP/XF as
address1 and address2, respectively (%40502 = %101 in bits 0 through 7 and %102 in
bits 8 through 15). The SETMODE 16 call defines the station as a multipoint tributary,
sets the station to respond only to the configured address1 and address2 station
addresses, and the station defines the link as half-duplex. Both stations are in disconnect
mode.
The supervisor application uses DEFINELIST to pass a station list to EnvoyACP/XF.
The station list contains the addresses of all the tributary stations that the supervisor will
be controlling.
SUPERVISOR
! Each station address is one octet
! left-justified (bits 0-7)
! followed by a NULL (all zeros)
! in bits 8-15
LITERAL addr^a = %40400, ! A,NULL
addr^b = %41000, ! B,NULL
addr^c = %41400, ! C,NULL
addr^d = %42000; ! D,NULL
entry^size = 4, ! entry size (4 words)
num^entries = 4, ! number of entries in list
poll^count = 4, ! number of entries in list
poll^type = 0, ! continuous polling
INT .STATION^LIST [0:15] :=
[ addr^a,3 * [0], ! Station A