lcd12864显示abcdefg.avr

来自「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」· AVR 代码 · 共 126 行

;由FLASHMAN编写,QQ28479691
;lcd12864显示程序
;在第一行和第二行显示abcdefg
;ME300B上运行成功

.include "8515def.inc"
.equ rs=0
.equ rw=1
.equ en=2
.equ psb=3
.equ rst=5

.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,$80
	rcall WrOp
	
	ldi r16,'a'
	rcall WrDat
	
	ldi r16,'b'
	rcall WrDat
	
	ldi r16,'c'
	rcall WrDat	
	
	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
;------------------------------------------ok
LcdIni:
	cbi portc,rst
	ldi r16,250
l_lp:
	dec r16
	brne l_lp
	sbi portc,rst
	nop
	nop
	nop
	sbi portc,psb

	ldi r16,$30
	rcall WrOp
	
	ldi r16,$01
	rcall WrOp
	
	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
	nop
	nop
	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
	nop
	nop
	cbi portc,en
	
	ret
;-----------------------------------------
check:
;忙位检测
	cbi ddra,7			;设置PA的第七位为读入
	sbi porta,7			;上拉电阻
	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
;-----------------------------------------