请教弄过指纹模块的高手或前辈，下面程序哪里出错使指纹模块无应答，与电脑通信正常

#include <reg52.h>

#include <string.h>



typedef unsigned char uchar;

typedef unsigned int uint;

//#define MAXSIZE 50



sbit LED1 = P1^0;

sbit LED8 = P1^1;

sbit LED2 = P1^2;

sbit K1 = P2^7;

uchar a = 0;

uint summas;

uchar sum[2];

uchar confcode;           //指纹模块应答确认码

//uchar  arr_mem[MAXSIZE];

//uchar head, tail;



//FINGERPRINT通信协议定义



unsigned char  FP_Pack_Head[6] = {0xEF,0x01,0xFF,0xFF,0xFF,0xFF}; //协议包头



unsigned char  PF_Verify_Pwd[10] = {0x01, 0x00, 0x07, 0x13, 0X00, 0X00, 0X00, 0X00, 0x00, 0x1b};  // 验证口令， 模块才正常工作 



unsigned char  FP_Get_Img[6] = {0x01,0x00,0x03,0x01,0x00,0x05};         //获得指纹图像

 

unsigned char  FP_Change_Com[8] = {0x01,0x0,0x05,0x0e,0x04,0x01,0x0,0x19}; //修改波特率 9600   

   

unsigned char  FP_Templete_Num[6] ={0x01,0x00,0x03,0x1D,0x00,0x21 };  //获得模版总数 



unsigned char  FP_Search[11]={0x01,0x0,0x08,0x04,0x01,0x0,0x0,0x03,0xA1,0x0,0xB2}; //搜索指纹搜索范围0 - 929



unsigned char  FP_Search_0_9[11]={0x01,0x00,0x08,0x04,0x01,0x00,0x00,0x00,0x13,0x00,0x21};  //搜索0-9号指纹 



unsigned char  FP_Img_To_Buffer1[7]={0x01,0x00,0x04,0x02,0x01,0x00,0x08};        //将图像放入到BUFFER1



unsigned char  FP_Img_To_Buffer2[7]={0x01,0x00,0x04,0x02,0x02,0x00,0x09};        //将图像放入到BUFFER2 



unsigned char  FP_Reg_Model[6]={0x01,0x0,0x03,0x05,0x0,0x09};         //将BUFFER1跟BUFFER2合成特征模版 

 

unsigned char code FP_Delet_All_Model[6]={0x01,0x0,0x03,0x0d,0x00,0x11}; //删除指纹模块里所有的模版



volatile unsigned char xdata FP_Save_Finger[9]={0x01,0x00,0x06,0x06,0x01,0x00,0x0B,0x00,0x19}; //将BUFFER1中的特征码存放到指定的位置



volatile unsigned char xdata FP_Delete_Model[10]={0x01,0x00,0x07,0x0C,0x0,0x0,0x0,0x1,0x0,0x0}; //删除指定的模版





void UART_Init()  // 通信波特率9600

{

TMOD = 0x20;

//        PCON = 0x80;

TH1  = 0xfd;

TL1  = 0xfd;

TR1  = 1;

SM0  = 0;

SM1  = 1;

REN  = 1;

ES   = 1;

EA   = 1;

}

void UART_Send_Byte(uchar c) // 发送一个字节的数据

{

//        TI = 0;

SBUF = c;

while(!TI);

TI = 0;

}



void Delay_1ms(uint z)

{

uchar x, y;

for (x = z; x > 0; x--)

for (y = 110; y > 0; y--);        

}



uchar Verify_Pwd()    // 与指纹模块实现握手， 握手成功方能实行下一步动作

{

uchar i;

Delay_1ms(20);

for (i = 0; i < 6; i++)

{

UART_Send_Byte(FP_Pack_Head[i]);   //发送指令包头

Delay_1ms(20);

}

Delay_1ms(20);

for (i = 0; i < 10; i++)

{

UART_Send_Byte(PF_Verify_Pwd[i]);  //发送指令数据

Delay_1ms(20);

}

for (i = 0; i < 9; i++)        //  指纹应答数据前9个字节

{

while (!RI);

RI = 0;

Delay_1ms(20);

}

Delay_1ms(20);

while (!RI);

RI = 0;

confcode = SBUF;         // 将应答数据第10个字节也就是确认码读出

Delay_1ms(20);

while (!RI);

RI = 0;

sum[1] = SBUF;

Delay_1ms(20);

while (!RI);

RI = 0;

sum[0] = SBUF;

Delay_1ms(20);

summas = (sum[1] << 8) + sum[0];

if (confcode == 0x00)        // 确认码正确就返回1 ， 错误就返回0

return 1;

else

return 0;

}





main()

{



UART_Init();

while (1)

{



//        UART_Send_Byte(0xEF);

//        if (a = 1)

//        LED1 = 0;



if (Verify_Pwd())

{

LED8 = 0;

Delay_1ms(2000);

break;

}

else

LED2 = 0;

}

}