;----------------------------------------------------------------------------------------
;** Funktionen: put1620byte -> Schreibt den Wert von ds1620byte in DS1620
;----------------------------------------------------------------------------------------

put1620byte:  	setb p1.0    		; CLK High
    		setb p1.1    		; RST = HIGH
  		mov b, #8              	; Schleifenzähler in b
		mov a, ds1620byte

wordlength:  	clr p1.0                		; CLK low
                	rrc a                  		 ; auszugebenes Bit ins Carry
                	mov p1.2,c             	 ; Carry an dq
    		setb p1.0              		; CLK high
    		djnz b,wordlength

go_back:  	ret


;----------------------------------------------------------------------------------------
;** Funktionen: get1620byte -> liest den Wert von DS1620 in 1620byte
;----------------------------------------------------------------------------------------

get1620byte:	mov p1, #2		;| DQ = HIGH=INPUT

		setb p1.0    		; CLK High
    		setb p1.1    		; RST = HIGH

		mov bit_stelle2, #7 
wordlength2:	mov a, bit_stelle2
		cjne a, #7, vorzeichenbit
		
		clr p1.0			;|CLOCK= LOW
		inc bit_stelle2
		setb p1.0			;|CLOCK= HIGH
		mov a, p1
		anl a, #2
		cjne a, #2, write_0

write_1:		mov a, ds1620byte
		setb c
		rrc a
		mov ds1620byte, a
		jmp wordlength2

write_0:		mov a, ds1620byte
		clr c
		rrc a
		mov ds1620byte, a
		jmp wordlength2

vorzeichenbit:	clr p1.0			;|CLOCK= LOW
		inc bit_stelle2
		setb p1.0			;|CLOCK= HIGH
		mov a, p1
		anl a, #2
		cjne a, #2, kein_vorzeichen
		mov vorzeichen, #1
		mov p1, #0		;|OUTPUT
		ret
kein_vorzeichen:	mov vorzeichen, #0
		mov p1, #0		;|OUTPUT
		ret

;----------------------------------------------------------------------------------------
;** Funktionen: liest Temperatur von DS1620 in 1620byte
;----------------------------------------------------------------------------------------

get_temperatur:	;setb p1.0    		; CLK High
		;setb p1.1			;|RST = HIGH   |
		mov ds1620byte, #0EEh	;|	         |  Start
		call put1620byte		;|	         |Convert
		clr p1.1			;|RST = LOW    |



		;setb p1.0    		; CLK High
		;setb p1.1			;|RST = HIGH   |
		mov ds1620byte, #022h	;|	         |   Stop
		call put1620byte		;|	         | Convert
		clr p1.1			;|RST = LOW    |


		setb p1.0    		; CLK High
		setb 1.1			;|RST = HIGH   |
		mov ds1620byte, #0AAh	;|	         |  
		call put1620byte		;|	         |read value in
		mov ds1620byte, #0	;|	         |"temperatur"
		call get1620byte		;|	         |
		
		clr p1.1			;|RST = LOW    |
		mov a, ds1620byte		;|	         |  
		mov temperatur, a		;|	         |  
		ret