pshiftw.asm

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; P-Code Aritmetic Library (c)Copyright 2000, 2001, Radek Benedikt
;	[e-mail], http://benedikt.lphard.cz

	.global	pshiftw
	.text
;
; *** PSHIFTW *** SHIFT word (cpu IDATA mem), with constant  ***
; pshiftw buffer_addr, const
;	R7,	R5
pshiftw:MOV	A,R7
	MOV	R0,A
	MOV	A,@R0
	MOV	R2,A
	INC	R0
	MOV	A,@R0
	MOV	R3,A
	MOV     A,R5
	JB	Acc.7,pshiftright0
pshiftleft:
	MOV	A,R3
	ADD	A,R3
	MOV	R3,A
	MOV	A,R2
	ADDC	A,R2
	MOV	R2,A
	DJNZ	R5,pshiftleft
	SJMP	pshiftend
pshiftright0:
	CPL	A
	INC	A
	MOV	R5,A
pshiftright:
	CLR	C
	MOV	A,R2
	RRC	A
	MOV	R2,A
	MOV	A,R3
	RRC	A
	MOV	R3,A
	DJNZ	R5,pshiftright
pshiftend:
	MOV	A,R3
	MOV	@R0,A
	DEC	R0
	MOV	A,R2
	MOV	@R0,A
	RET
	;; END