div2x1.asm

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	.text

.global	div2x1

;##########
;# div2x1 #
;##########
;
; deleni 2 byte (r2(MSB),r3(LSB))
; deleno 1 byte r6
; vysledek je v (r2(MSB),r3(LSB))
; zbytek po deleni je v (r0(MSB),r1(LSB))
div2x1:	CLR	A
       	mov	R0,a
       	MOV	R1,A
       	MOV	B,#16	;16 bit
div20: 	CLR	C
       	MOV	A,r3
       	RLC	A
       	MOV	r3,A
       	MOV	A,r2
       	RLC	A
       	MOV	r2,A
       	MOV	A,R1
       	RLC	A
       	MOV	R1,A
       	MOV	A,R0
       	RLC	A
       	MOV	R0,A
       	MOV	A,R1
       	SUBB	A,r6
       	MOV	A,R0
       	SUBB	A,#0
       	JC	div21
       	MOV	R0,A
       	MOV	A,R1
       	SUBB	A,r6
       	MOV	R1,A
       	INC	r3
div21: 	DJNZ	B,div20
	ret

	;; END