自己设计了一个程序，但是LCD不显示，不知道问题在哪，求大神帮忙看下/*************定义接口********************
P0------DB0～DB7 (LCD1602)
P2.5------RS (LCD1602)
P2.6------RW (LCD1602)
P2.7------E (LCD1602)
P3.5------SOUNDER (蜂鸣器）
P3.6------SCK (SHT10) //时钟
P3.7------DATA (SHT10) //数据
*****************************************/
#include <AT89x52.h>
#include <intrins.h>
#include <math.h> //Keil library
#include <stdio.h> //Keil library
#define TEMPUP 24 //温度上限, 达到该温度蜂鸣器报警
typedef unsigned char BYTE;
typedef unsigned int WORD;
typedef bit BOOL ;
/*******************************************/
sbit buzzer = P3^5; //蜂鸣器
BOOL start;
/******************************************/

//************第一部分LCD1602设置******
//START*************************************/
#define LCD_DB P0
sbit LCD_RS=P2^5; //P2^5是p2.5
sbit LCD_RW=P2^6; //P2^6是p2.6
sbit LCD_E=P2^7; //P2^7是p2.7
/******定义函数****************/
#define uchar unsigned char
#define uint unsigned int
void LCD_init(void); //初始化函数
void LCD_write_command(uchar command); //写指令函数
void LCD_write_data(uchar dat); //写数据函数
void LCD_disp_char(uchar x,uchar y,uchar dat);//在某个屏幕位置上显示一个字符,X（0-15),y(1-2)
void LCD_disp_str(uchar x,uchar y,uchar *str); //LCD1602显示字符串函数
void delay_n10us(uint n); //延时函数

/*--------------------------------------
;初始化LCD1602
;-------------------------------------*/
void LCD_init(void)
{
delay_n10us(10);
LCD_write_command(0x38);//设置8位格式，2行，5x7
delay_n10us(10);
LCD_write_command(0x0c);//整体显示，关光标，不闪烁
delay_n10us(10);
LCD_write_command(0x06);//设定输入方式，增量不移位
delay_n10us(10);
LCD_write_command(0x01);//清除屏幕显示
delay_n10us(100); //延时清屏，延时函数，延时约n个10us
}

/*--------------------------------------
;LCD1602写指令函数
;-------------------------------------*/
void LCD_write_command(uchar dat)
{
delay_n10us(10);
LCD_RS=0; //指令
LCD_RW=0; //写入
LCD_E=1; //允许
LCD_DB=dat;
delay_n10us(10);
LCD_E=0;
delay_n10us(10);
}

/*--------------------------------------
;LCD1602写数据函数
;-------------------------------------*/
void LCD_write_data(uchar dat)
{
delay_n10us(10);
LCD_RS=1; //数据
LCD_RW=0; //写入
LCD_E=1; //允许
LCD_DB=dat;
delay_n10us(10);
LCD_E=0;
delay_n10us(10);
}
/*--------------------------------------
;LCD1602显示一个字符函数，在某个屏幕位置上显示一个字符,X（0-15),y(1-2)
;-------------------------------------*/
void LCD_disp_char(uchar x,uchar y,uchar dat)
{
uchar address;
if(y==1)
address=0x80+x;
else
address=0xc0+x;
LCD_write_command(address);
LCD_write_data(dat);
}

/*--------------------------------------
;LCD1602显示字符串函数，在某个屏幕起始位置{X（0-15),y(1-2)}上显示一个字符串
;-------------------------------------*/
void LCD_disp_str(uchar x,uchar y,uchar *str)
{
uchar address;
if(y==1)
address=0x80+x;
else
address=0xc0+x;
LCD_write_command(address);
while(*str!='')
{
LCD_write_data(*str);
str++;
}
}

/*--------------------------------------
;延时函数，延时约n个10us
;-------------------------------------*/
void delay_n10us(uint n) //延时n个10us@12M晶振
{
uint i;
for(i=n;i>0;i--)
{
_nop_();_nop_();_nop_();_nop_();_nop_();_nop_();
}
}
//***************第一部分LCD1602设置*******
//END****************************************
//*************第二部分SHT10设置*************
//START****************************************
sbit SCK = P3^6; //定义通讯时钟端口
sbit DATA = P3^7; //定义通讯数据端口
typedef union         //定义了两个共用体
{ unsigned int i;
float f;
}value;

enum {TEMP,HUMI}; //TEMP=0,HUMI=1

#define noACK 0 //用于判断是否结束通讯
#define ACK 1 //结束数据传输
              //adr command r/w
#define STATUS_REG_W 0x06 //000 0011 0
#define STATUS_REG_R 0x07 //000 0011 1
#define MEASURE_TEMP 0x03 //000 0001 1
#define MEASURE_HUMI 0x05 //000 0010 1
#define RESET 0x1e //000 1111 0

/****************定义函数****************/
void s_transstart(void); //启动传输函数
void s_connectionreset(void); //连接复位函数
char s_write_byte(unsigned char value);//SHT10写函数
char s_read_byte(unsigned char ack); //SHT10读函数
char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode);//测量温湿度函数
void calc_SHT10(float *p_humidity ,float *p_temperature);//温湿度补偿

/*--------------------------------------
;启动传输函数
;-------------------------------------*/
void s_transstart(void)
// generates a transmission start
// _____ ________
// DATA: |_______|
// ___ ___
// SCK : ___| |___| |______
{
DATA=1; SCK=0; //Initial state
_nop_();
SCK=1;
_nop_();
DATA=0;
_nop_();
SCK=0;
_nop_();_nop_();_nop_();
SCK=1;
_nop_();
DATA=1;
_nop_();
SCK=0;
}

/*--------------------------------------
;连接复位函数
;-------------------------------------*/
void s_connectionreset(void)
{
unsigned char i;
DATA=1; SCK=0; //Initial state
for(i=0;i<9;i++) //9 SCK cycles
{
SCK=1;
SCK=0;
}
s_transstart(); //transmission start
}

/*--------------------------------------
;SHT10写函数
;-------------------------------------*/
char s_write_byte(unsigned char value)
//----------------------------------------------------------------------------------
// writes a byte on the Sensibus and checks the acknowledge
{
unsigned char i,error=0;
for (i=0x80;i>0;i/=2) //shift bit for masking
{
if (i & value) DATA=1; //masking value with i , write to SENSI-BU
else DATA=0;
SCK=1; //clk for SENSI-BUS
_nop_();_nop_();_nop_(); //pulswith approx. 3 us
SCK=0;
}
DATA=1; //release DATA-line
SCK=1; //clk #9 for ack
error=DATA; //check ack (DATA will be pulled down by SHT11),DATA在第9个上升沿将被SHT10自动下拉为低电
_nop_();_nop_();_nop_();
SCK=0;
DATA=1; //release DATA-line
return error; //error=1 in case of no acknowledge //返回：0成功，1失败
}

/*--------------------------------------
;SHT10读函数
;-------------------------------------*/
char s_read_byte(unsigned char ack)
// reads a byte form the Sensibus and gives an acknowledge in case of "ack=1"
{
unsigned char i,val=0;
DATA=1; //release DATA-line
for (i=0x80;i>0;i/=2) //shift bit for masking
{ SCK=1; //clk for SENSI-BUS
if (DATA) val=(val | i); //read bit
_nop_();_nop_();_nop_(); //pulswith approx. 3 us
SCK=0;
}
if(ack==1)DATA=0; //in case of "ack==1" pull down DATA-Line
else DATA=1; //如果是校验(ack==0)，读取完后结束通讯
_nop_();_nop_();_nop_(); //pulswith approx. 3 us
SCK=1; //clk #9 for ack
_nop_();_nop_();_nop_(); //pulswith approx. 3 us
SCK=0;
_nop_();_nop_();_nop_(); //pulswith approx. 3 us
DATA=1; //release DATA-line
return val;
}
/*--------------------------------------
;测量温湿度函数
;-------------------------------------*/
char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode)
  // makes a measurement (humidity/temperature) with checksum
{
unsigned error=0;
unsigned int i;

s_transstart(); //transmission start
switch(mode){ //send command to sensor
case TEMP : error+=s_write_byte(MEASURE_TEMP); break;
case HUMI : error+=s_write_byte(MEASURE_HUMI); break;
default : break;
}
for (i=0;i<65535;i++)
if(DATA==0) break; //wait until sensor has finished the measurement
if(DATA) error+=1; // or timeout (~2 sec.) is reached
*(p_value) =s_read_byte(ACK); //read the first byte (MSB)
*(p_value+1)=s_read_byte(ACK); //read the second byte (LSB)
*p_checksum =s_read_byte(noACK); //read checksum
return error;
}
/*--------------------------------------
;温湿度补偿函数
;-------------------------------------*/
void calc_SHT10(float *p_humidity ,float *p_temperature)
// calculates temperature [C] and humidity [%RH]
// input : humi [Ticks] (12 bit)
// temp [Ticks] (14 bit)
// output: humi [%RH]
// temp [C]
{ const float C1=-4.0; // for 12 Bit
const float C2=+0.0405; // for 12 Bit
const float C3=-0.0000028; // for 12 Bit
const float T1=+0.01; // for 14 Bit @ 5V
const float T2=+0.00008; // for 14 Bit @ 5V
float rh=*p_humidity; // rh: Humidity [Ticks] 12 Bit
float t=*p_temperature; // t: Temperature [Ticks] 14 Bit
float rh_lin; // rh_lin: Humidity linear
float rh_true; // rh_true: Temperature compensated humidity
float t_C; // t_C : Temperature [C]

t_C=t*0.01 - 40; //calc. temperature from ticks to [C]
rh_lin=C3*rh*rh + C2*rh + C1; //calc. humidity from ticks to [%RH]
rh_true=(t_C-25)*(T1+T2*rh)+rh_lin; //calc. temperature compensated humidity [%RH]
if(rh_true>100)rh_true=100; //cut if the value is outside of
if(rh_true<0.1)rh_true=0.1; //the physical possible range
*p_temperature=t_C; //return temperature [C] *p_humidity=rh_true; //return humidity[%RH]
}
//**********第二部分SHT10设置***************
//END****************************************
//*********主函数*****************
void main(void)
{
value humi_val,temp_val;
unsigned char error,checksum;
unsigned int wendu,shidu;
LCD_init();
s_connectionreset();
LCD_disp_str(0,1,"TE ");
LCD_disp_str(0,2,"RH ");
//*********初始化温度显示区*********
LCD_disp_str(2,1,"TTT.T C");
//*********初始化湿度显示区*********
LCD_disp_str(2,2,"RRR.R%");
delay_n10us(20000); //延时0.2s
while(1)
{ error=0;
error+=s_measure((unsigned char*) &humi_val.i,&checksum,HUMI);
error+=s_measure((unsigned char*) &temp_val.i,&checksum,TEMP);
if(error!=0) s_connectionreset();
else
{ humi_val.f=(float)humi_val.i;
temp_val.f=(float)temp_val.i;
calc_SHT10(&humi_val.f,&temp_val.f);
wendu=10*temp_val.f;
LCD_disp_char(2,1,wendu/1000+'0'); //显示温度百位
LCD_disp_char(3,1,(wendu%1000)/100+'0'); //显示温度十位
LCD_disp_char(4,1,(wendu%100)/10+'0'); //显示温度个位
LCD_disp_char(6,1,(wendu%10)+'0'); //显示温度小数点后第一位
shidu=10*humi_val.f;
LCD_disp_char(2,2,shidu/1000+'0'); //显示湿度百位
LCD_disp_char(3,2,(shidu%1000)/100+'0'); //显示湿度十位
LCD_disp_char(4,2,(shidu%100)/10+'0'); //显示湿度个位
LCD_disp_char(6,2,(shidu%10)+'0'); //显示湿度小数点后第一位
}
delay_n10us(80000); //延时约0.8s }
}
}