PDP-10 Archive: decus/20-0125/waitch.for from decuslib20-04

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	INTEGER FUNCTION WAITCH(IDUM)
C************************************************************
C
C  THIS ROUTINE IS USED TO RECEIVE ONE ASCII
C  CHARACTER FROM THE GT40. ONLY THE LOW
C  ORDER 6 BITS OF THE CHARACTER ARE RETAINED.
C
C  POSSIBLE ERRORS:
C	NONE
C
C  WARNING:
C	ONCE THIS ROUTINE IS ENTERED, IT WAITS
C	FOR THE GT40 TO TRANSMIT A CHARACTER. IF
C	NO CHARACTER IS FORTHCOMING (I.E. GT40 HUNG)
C	THEN THIS ROUTINE ALSO HANGS UP. UNFORTUNATELY
C	DUE TO SWAPPING, AND THE FACT THAT THE GT40 MIGHT
C	BE BUSY BEFORE IT CAN SEND A CHARACTER, THERE IS
C	NO VALID WAY TO TIME HOW LONG A CHARACTER SHOULD
C	TAKE.
C
C  ROUTINES CALLED:
C	GETCHR - RETURNS ONE ASCII CHARACTER FROM GT40
C	         RETURNS -1 IF NO CHARACTER PRESENT
C
C************************************************************
	INTEGER GETCHR

100	I = GETCHR(0)
	IF(I .EQ. -1) GO TO 100
	WAITCH = I .AND. "77
	RETURN
	END