; SUBROUTINE TO SWAP BYTES IN A USER ARRAY
; PATTERNED AFTER ENTRY IN CODE 664 FTIO
; 13JUN78-0900
;
;*************************************************************************;
;	CALL SWABI(ARRAY,NBYTES)
;		WHERE ARRAY IS A DATA ARRAY IN WHICH BYTES ARE TO BE SWAPPED
;		      NBYTES IS NUMBER OF BYTES TO BE SWAPPED
;		ROUTINE CALLS EXIT$S FOR WRONG NUMBER OF ARGUMENTS
;*************************************************************************;
;
	.TITLE	SWABI
	.IDENT	/V001/
	.MCALL	EXIT$S
;
SWABI::
; SAVE REGS
	.IRP	X,<R1,R2>
	MOV	X,-(SP)
	.ENDM
;
; CHECK NUMBER OF ARGS
	CMP	#2,(R5)				
	BEQ	5$
	EXIT$S
;
; SET UP LOOP - NBYTES/2 FOR NUMBER OF WORDS
5$:
	MOV	@4(R5),R1
	ASR	R1
	MOV	2(R5),R2
;
; SWAP BYTES
10$:
	SWAB	(R2)+
	SOB	R1,10$
;
; RESTORE REGS
	.IRP	X,<R2,R1>
	MOV	(SP)+,X
	.ENDM
;
; RETURN
	RTS	PC
	.END