Texas Instruments 990 User Manual page 122

Applications Programming
C THIS TASK WAITS ON MESSAGES FROM A PRIMARY TASK. WHEN A
C MESSAGE IS RECEIVED THE TASK RESPONDS WITH A MESSAGE OF
C ITS OWN OR SENDS THE RECEIVED MESSAGE BACK DEPENDING ON
C THE INPUT CHARACTER COUNT
C
INTEGER*2 DID,SID,STATUS,COUNT,BUFFER{2),OPTION,BUFLEN,BACK{2)
DATA DID/O/, SID/O/,OPTION/2/, BUFLEN/4/
DATA
BACK{1),BACK{2)/~BYE ~/
C
C CALL ACTIVATION SERVICES TO REQUEST ACTIVATION FROM A TIME
C DELAY IF A MESSAGE COMES IN FOR MY SID
C
4 CALL WKUP4D{OPTION,STATUS)
C
C DO A TIME DELAY
C
CALL WAIT{5,2,STATUS)
C
C SEE IF ANY MESSAGES HAVE COME IN
C
C
CALL READ4D{BUFFER,BUFLEN,COUNT,DID,SID,STATUS)
IF (STATUS .NE. 0) GO TO 4
IF (COUNT .NE. 4) GO TO 5
C WRITE REPLY MESSAGE IF INPUT CHARACTER COUNT IS AS EXPECTED
C
C
CALL WRIT4D{BACK,BUFLEN,DID,SID,STATUS)
GO
ro
4
C RETURN INPUT BUFFER IF INPUT CHARACTER NOT AS EXPECTED
C
5 CALL WRIT4D{BUFFER,COUNT,DID,SID,STATUS)
GO TO 4
END
Figure 4-9 FORTRAN Program in Secondary Station
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