程序代码：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <sys/ipc.h>
#include <linux/fb.h>
#include <sys/types.h>
#include <stdlib.h>
#include "font_8x16.h"
       
//画好显示区域，x方向左右空一个字，y方向上下空一个字节
#define Start_x 16
#define Start_y 8
#define End_x    (320 - 16)
#define End_y    (240 - 8)

struct fb_var_screeninfo vinfo;
struct fb_fix_screeninfo finfo;
char *fbp = 0;
long screensize = 0;
long location = 0;
int r = 0;   
unsigned int number;
int fk;
char buttom_status[6];
int next_page = 0;
unsigned int page[1000];
unsigned int  count = 0;
int page_n;


//清屏
void Clean_screen()
{
    memset(fbp, 0xf8, screensize);
}

void Draw_text16X16(long location_t,unsigned short color, const unsigned char ch[])
{
    int i, j;
    unsigned char mask, buffer;
    for (i = 0; i < 16; i++)
    {
        mask = 0x80;
        buffer = ch[i * 2];
        location_t +=  finfo.line_length;
        for (j = 0; j < 8; j++) {
            if ((buffer & mask))
                {    
                    *(fbp +location_t + j * vinfo.bits_per_pixel / 8) = color;
                    *(fbp +location_t + j * vinfo.bits_per_pixel / 8 + 1) = color>>8;
                  }
             mask = mask >> 1;
         }

        mask = 0x80;
        buffer = ch[i * 2 + 1];
        for (j = 0; j < 8; j++)
        {
            if ((buffer & mask))
                {
                    *(fbp +location_t + (8 + j) * vinfo.bits_per_pixel / 8) = color;
                    *(fbp +location_t + (8 + j) * vinfo.bits_per_pixel / 8 + 1) = color>>8;
                }
            mask = mask >> 1;
        }
    }       
}

void Draw_text16X8(long location_t,unsigned short color, const unsigned char ch[])
{
    int i, j;
    unsigned char mask, buffer;

    for (i = 0; i < 16; i++)
    {
        mask = 0x80;
        buffer = ch[i];
        location_t +=  finfo.line_length;
        for (j = 0; j < 8; j++)
        {
            if ((buffer & mask))
                {
                    *(fbp +location_t + j * vinfo.bits_per_pixel / 8) = color;
                    *(fbp +location_t + j * vinfo.bits_per_pixel / 8 + 1) = color>>8;
                }
            mask = mask >> 1;
        }
    }
}

void Next_screen(long location_t, unsigned short color, unsigned char ch[], int Flag)
{
    int ret;
    while (1)
    {   
        ret = read(fk, buttom_status, 6);
        if (ret < 0)
        {
            printf("read buttom status err\n");
        }
   
        if (buttom_status[0] == '1')
        {
            next_page = 1;
        }
        if (next_page == 1)
        {
            next_page = 0;   
            //清屏
            Clean_screen();
            //重新定一屏的起始位置
            location = location_t;
            r = 0;
            page[page_n] = count;
            page_n += 1;
            count = 0;
            //打印汉字
            if (Flag == 1)
                Draw_text16X16(location, color, ch);
            else if (Flag == 0)
                   Draw_text16X8(location, color, ch);
            break;
        }else
        {
            continue;
        }
    }
}
   
void Next_line(long location_t,int r_t)
{
    location = location_t +  16 * r_t * finfo.line_length;
}

void Put_lcd_Hz(long location_t, unsigned short color, unsigned char ch[])
{
    int Flag_Hz = 0;  //汉字标志位，默认为字符非汉字
    //计算字最右边的点有没有越界,判断位置需不需要换行
    location += 16 * (vinfo.bits_per_pixel / 8);
    //这个针对320x240的屏，最后一个字的点去除刚好整除为0，可以考虑用下面的方法——通用一些
    //if ((location % (vinfo.xres * vinfo.bits_per_pixel / 8)) < (16 * vinfo.bits_per_pixel /8))
    if((location - (Start_y + 16 * r) * finfo.line_length)  > End_x * (vinfo.bits_per_pixel / 8))
    {
        //计算字最下边的点有没有越界，判断需不需要换屏
        if ((location + 16 * finfo.line_length) > (End_x * (vinfo.bits_per_pixel / 8) + End_y * finfo.line_length))
        {
            Flag_Hz = 1;
            Next_screen(location_t, color, ch, Flag_Hz);
        }else
        {
            r = r + 1;
            Next_line(location_t,r);
        }
    }
    //字最右边的点没有越界,位置要记得复位
    else
        location -= 16 * (vinfo.bits_per_pixel / 8);
    //打印16X16字
       Draw_text16X16(location, color, ch);
    //指向下一个字或字符的起始位置
    location += 16 * (vinfo.bits_per_pixel / 8);
}

void Put_lcd_CH(long location_t, unsigned short color, unsigned char ch[])
{
    int Flag_Hz = 0;  //汉字标志位，默认为字符非汉字
    //计算字最右边的点有没有越界,判断位置需不需要换行
    location += 8 * (vinfo.bits_per_pixel / 8);
    //判断位置需不需要换行
    if ((location - (Start_y + 16 * r) * finfo.line_length) > End_x * (vinfo.bits_per_pixel / 8))       
    {
        //计算字最下边的点有没有越界，判断需不需要换屏
        if ((location + 16 * finfo.line_length) > (End_x * (vinfo.bits_per_pixel / 8) + End_y * finfo.line_length))
        {
            Next_screen(location_t, color, ch, Flag_Hz);
        }else
        {
            r = r + 1;
            Next_line(location_t,r);
        }
    }
    else
        location -= 8 * (vinfo.bits_per_pixel / 8);
   
    //打印16X8字
       Draw_text16X8(location, color, ch);
    location += 8 * (vinfo.bits_per_pixel / 8);
}

//换行符处理函数
void do_line_break(long location_t)
{
    //换行有可能是刚刚好也是换屏的时候
    if ((location + 16 * finfo.line_length) > (End_x * (vinfo.bits_per_pixel / 8) + (End_y - 1) * finfo.line_length))
    {
        Next_screen(location_t, 0, "next_screen", 2);
    }else
    {
        r = r + 1;
        Next_line(location_t, r);
    }
}   
   
int main(void)
{
    int fd, fp;                                            //fp----LCD   fd------.txt 
    FILE *Hz_fp;                                        //Hz_fp-----HZK16
    struct stat txt_stat;                                //文件状态，可获得文件的字节数
    off_t file_size;                                    //文件字节数
    unsigned int hz_index, assic_index;                    //汉字在汉字库中的偏移量
    unsigned char *buffer;                                //存放文本文件内容的缓存
    unsigned char hz_buf[32], assic_buf[16];            //存放字模的数组
    long location_t;                                    //保存一屏的起始位置    

    //打开LCD设备
    fp = open("/dev/fb0", O_RDWR);
    if(fp < 0)
    {
        printf("Error : Can not open framebuffer device\n");
        exit(1);
    }
    puts("hello world.\n");
    printf("open framebuffer device\n");
   
   
    //初始化lcd   
    if (ioctl(fp, FBIOGET_FSCREENINFO, &finfo))
    {
        printf("Error reading fixed information\n");
        exit(2);
    }
    if (ioctl(fp, FBIOGET_VSCREENINFO, &vinfo))
    {
        printf("Error reading fixed information\n");
        exit(3);

    }
    screensize = vinfo.xres * vinfo.yres * vinfo.bits_per_pixel / 8;
   
    fbp = (char *)mmap(0, screensize, PROT_READ | PROT_WRITE, MAP_SHARED, fp, 0);
    if ((int)fbp == -1)   
    {
        printf("Error: failed to map framebuffer device to memory.\n");
        exit(4);
    }
     //清屏   
    Clean_screen();
    //一屏的起始位置location_t
    location_t = Start_x * (vinfo.bits_per_pixel / 8) + Start_y * finfo.line_length;
    //location做一个全局变量，用于确定每个汉字或字符的输出位置
    location = location_t;

     fk = open("/dev/buttons", O_RDWR);
    if (fk < 0)
    {
        printf("can't open /dev/buttons\n");
        return -1;
    }

    //打开16x16的汉字库
    Hz_fp = fopen("HZK16", "rb");
    if (Hz_fp == NULL)
    {
        printf("HZK16 can't open!\n");
        return (-1);
    }
    //打开txt文本
    fd = open("/home/1.txt", O_RDONLY);
    if (fd < 0)   
    {
        printf("txt can't open!\n");
        return -1;
    }
    //通过struct stat结构体求得文本的字节数
    fstat(fd, &txt_stat);
    file_size = txt_stat.st_size;
    //开辟与文本字节数一样大小的缓存
    buffer = (unsigned char *)malloc(file_size);
    //将申请到的缓存清零
    memset(buffer, 0, file_size);
    //一次性将文本的内容读到缓存中
    read(fd,buffer, file_size);

    while(*buffer != '\0')
    {
        //文本换行符
        if (*buffer == '\r' || *buffer == '\n') 
        {
            do_line_break(location_t); //换行符处理函数
            buffer += 1;
            continue;
        }
        //一个tab用四个字节代替
        if (*buffer == '\t')       
        {
            location += 32 * (vinfo.bits_per_pixel / 8);
            *buffer++;
            count += 1;
            continue;
        }
       
        if (*buffer == ' ' || *buffer == 0xa1)
        {
            location += 8 * (vinfo.bits_per_pixel / 8);
            *buffer++;
            count += 1;
            continue;
        }

        //判断汉字还是英文
        if (*buffer > 0xa1)   
        {
            hz_index = ((*buffer - 0xa1) * 94 + (*(buffer + 1) - 0xa1)) * 32;
            fseek(Hz_fp, hz_index, SEEK_SET);
            fread(hz_buf, 32, 1, Hz_fp);
            Put_lcd_Hz(location_t, 0xf800, hz_buf);
            //sleep(1);
            buffer += 2;
            count += 2;
        }
        else
        {
            assic_index = *buffer * 16;
            memcpy(assic_buf, &Assic[assic_index], 16);
            Put_lcd_CH(location_t, 0x07e0, assic_buf);
            count++;
            buffer++;
        }
    }
   
    munmap(fbp, screensize);
    close(fp);
    fclose(Hz_fp);
    close(fk);   
    close(fd);
    return 0;
}