lcd1602显示abcdefg.avr

这是购买伟纳电子的ME300B单片机开发板所配套的开发程序例程之AVR 实验例程部分。

;由FLASHMAN编写,QQ28479691
;lcd1602显示程序
;在第一行和第二行显示abc,第二行显示defg
;ME300B上运行成功

.include "8515def.inc"
.equ rs=0
.equ rw=1
.equ en=2

.org $000
	rjmp reset
reset:
.org $010
	ldi r16,low(ramend)
	ldi r17,high(ramend)
	out spl,r16
	out sph,r17
main:
	ser r16
	out ddra,r16
	out porta,r16
	out ddrc,r16
	out portc,r16
	
	rcall LcdIni
	
	ldi r16,$84
	rcall WrOp
	
	ldi r16,'a'
	rcall WrDat
	
	ldi r16,'b'
	rcall WrDat
	
	ldi r16,'c'
	rcall WrDat	
	
	ldi r16,$c4
	rcall WrOp
	
	ldi r16,'d'
	rcall WrDat

	ldi r16,'e'
	rcall WrDat
	
	ldi r16,'f'
	rcall WrDat
	
	ldi r16,'g'
	rcall WrDat
me:
	rjmp me
	;end of main
;------------------------------------------
LcdIni:
	ldi r16,$38
	rcall WrOp
	
	nop
	nop
	
	ldi r16,$06
	rcall WrOp
	
	ldi r16,$0c
	rcall WrOp
	ret
;------------------------------------------
WrOp:
;将R16命令字传送到LCD
	rcall check
	cbi portc,rs
	cbi portc,rw
	cbi portc,en
	out porta,r16
	sbi portc,en
	ldi r16,200
wo_lp:
	dec r16
	brne wo_lp
	cbi portc,en
	ret
;------------------------------------------
WrDat:
;将R16数据传送到LCD
	rcall check
	sbi portc,rs
	cbi portc,rw
	cbi portc,en
	out porta,r16
	sbi portc,en
	ldi r16,200
wd_lp:
	dec r16
	brne wd_lp
	cbi portc,en
	ret
;-----------------------------------------
check:
;忙位检测
	cbi ddra,7			;设置PA的第七位为读入
	cbi portc,rs
	sbi portc,rw
	sbi portc,en
c_lp:
	sbic pina,7			;为零时就退出
	rjmp c_lp
	cbi portc,en
	sbi ddra,7
	ret
;-----------------------------------------