[求助] avr16 1602LCD

#include<iom16.h>
#define uchar unsigned char
#define uint  unsigned int
#define rs1 PORTB|=1
#define rs0 PORTB&=~1
#define rw1 PORTB|=2
#define rw0 PORTB&=~2
#define en1 PORTB|=4
#define en0 PORTB&=~4

//===================================
 void delay(void)
{
  uchar j;
  for(j=0;j<120;j++);
}
void init(void)
{
  DDRB=0XFF;
  PORTB=0XFF;
}
void manglu(void)
{
  uchar a;
 
  do
{
  rw1;
  rs0;
  en1;
  DDRA=0X00;
  a=PINA;
  delay();
  en0;
 }while(a&0x80);
 
  DDRA=0XFF;
}
void xiezhiling(uint x)
{
  manglu();
  rs0;
  rw0;
  en0;
  PORTA=x;
  en1;
  delay();
  en0;
}

void zhiling(void)
{
  xiezhiling(0x38);
  xiezhiling(0x0c);
 
  xiezhiling(0x80);
 
}
void shuju(void)
{
  manglu();
  rs1;
  rw0;
  en1;
  PORTA=0X41;
}

void main(void)
{
  init();
  zhiling();
  shuju();
}

 

无法显示。 求错误