lcd_zeit:
	; 4 Millisekunden
	push	r16
	push	r17
	ldi		r16,CPU_Frequency/375000
lcd_zeit1:
	ldi		r17,0
lcd_zeit2:
	dec		r17
	brne	lcd_zeit2
	ldi		r17,0
lcd_zeit3:
	dec		r17
	brne	lcd_zeit3
	dec		r16
	brne	lcd_zeit1
	pop		r16
	pop		r17
	ret

lcd_wrcom:
	cbi		lcd_rs_port,lcd_rs_bit
	rjmp	lcd_wr
lcd_wrdat:
	sbi		lcd_rs_port,lcd_rs_bit
lcd_wr:
	push	r18
	push	r17

	rcall	lcd_wrcom1
	rcall	lcd_wrcom1

    ;kleine Zeitschleife 50 µS
    ldi		r17,CPU_Frequency/66000
lcd_loop:
	dec		r17
	brne	lcd_loop
	pop	r17
	pop	r18
	ret

lcd_wrcom1:
	swap	r16
	mov		r18,r16
	andi	r18,0b00001111
	in		r17,lcd_dat_port
	andi	r17,0b11110000
	or		r17,r18
	out		lcd_dat_port,r17
	nop
	nop
	nop
	sbi		lcd_en_port,lcd_en_bit
	nop
	nop
	nop
	cbi		lcd_en_port,lcd_en_bit
	ret


lcd_init:
	cbi		lcd_en_port,lcd_en_bit	;EN aus
	sbi		lcd_en_ddr,lcd_en_bit	;EN Ausgang aktiv
	sbi		lcd_rs_ddr,lcd_rs_bit	;RS Ausgang aktiv
	in		r16,lcd_dat_ddr
	ori		r16,0b00001111			;Datenausgänge aktiv
	out		lcd_dat_ddr,r16
	cbi		lcd_rs_port,lcd_rs_bit	;Kommandomodus

	ldi     r16,0b00111000	;8Bit,2Zeilen,5x7 pixel
	rcall	lcd_wrcom1
	rcall   lcd_zeit
	ldi     r16,0b00111000	;8Bit,2Zeilen,5x7 pixel
	rcall	lcd_wrcom1
	rcall   lcd_zeit
	ldi     r16,0b00111000	;8Bit,2Zeilen,5x7 pixel
	rcall	lcd_wrcom1
	rcall   lcd_zeit
	ldi     r16,0b00101000	;4Bit,2Zeilen,5x7 pixel
	rcall	lcd_wrcom1
	rcall   lcd_zeit

	ldi     r16,0b00000100	;Dislplay aus
	rcall   lcd_wrcom
	ldi     r16,0b00000001	;Display clear
	rcall   lcd_wrcom
	rcall   lcd_zeit
	ldi     r16,0b00000110	;Cursor rechts bei Eintrag
	rcall   lcd_wrcom
	ldi     r16,0b00001110 	;Display und Cursor ein
	rcall   lcd_wrcom
	rcall   lcd_zeit
	ret