字符设备驱动程序
Posted tommybjia
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一、 实验目的和要求
1. 学习嵌入式Linux的GPIO的使用方式；
2. 学习嵌入式Linux的Arduino接口库；
3. 学习使用面包板搭简单的外部电路；
4. 学习Linux设备驱动程序的开发过程；
5. 学习在内核中访问外设寄存器，操作外设的方法
二、 实验器材
1. Linux实验板卡一块；
2. 5V/1A电源一个；
3. microUSB线一根；
4. 面包板一块；
5. MAX7219驱动的8*8 LED矩阵一个；
6. 面包线若干；
7. MacOS一台；
8. USE－TTL串口线一根
9. 以太网线一根；
10. 交叉编译软件
三、 实验内容和原理
1．设计方法，画连接示意图；
2．在面包板上连线，完成外部电路；
3．编写C/C++程序，采用Arduino-ish库或虚拟文件系统访问GPIO，实现在矩阵上显示文字或图案；
4．编写字符设备驱动程序，直接访问GPIO控制寄存器，能将write()送来的单个字符在矩阵上显示出来
四、 实验过程和数据记录
1. 以下是实物连接图
GPIO端口使用bcm编号的23，24，25，对应WiringPi的4，5，6号端口，分别连接到驱动板的DIN，CS，CLK
2. 使用Wiring访问GPIO
在用户级别程序访问GPIO，使用Wiring是个很好的选择。
| #include <stdio.h> #include <wiringPi.h>
#define PIN_DIN 4 // GPIO端口号，对应驱动板的DIN #define PIN_CS 5 //GPIO端口号，对应驱动板的CS #define PIN_CLK 6 //GPIO端口号，对应驱动板的CLK
unsigned char disp1[256][8] = //ASCII码字体数据 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x0 0x7E, 0x81, 0xA5, 0x81, 0xBD, 0x99, 0x81, 0x7E , //0x1 0x7E, 0xFF, 0xDB, 0xFF, 0xC3, 0xE7, 0xFF, 0x7E , //0x2 0x6C, 0xFE, 0xFE, 0xFE, 0x7C, 0x38, 0x10, 0x00 , //0x3 0x10, 0x38, 0x7C, 0xFE, 0x7C, 0x38, 0x10, 0x00 , //0x4 0x38, 0x7C, 0x38, 0xFE, 0xFE, 0x7C, 0x38, 0x7C , //0x5 0x10, 0x10, 0x38, 0x7C, 0xFE, 0x7C, 0x38, 0x7C , //0x6 0x00, 0x00, 0x18, 0x3C, 0x3C, 0x18, 0x00, 0x00 , //0x7 0xFF, 0xFF, 0xE7, 0xC3, 0xC3, 0xE7, 0xFF, 0xFF , //0x8 0x00, 0x3C, 0x66, 0x42, 0x42, 0x66, 0x3C, 0x00 , //0x9 0xFF, 0xC3, 0x99, 0xBD, 0xBD, 0x99, 0xC3, 0xFF , //0xA 0x0F, 0x07, 0x0F, 0x7D, 0xCC, 0xCC, 0xCC, 0x78 , //0xB 0x3C, 0x66, 0x66, 0x66, 0x3C, 0x18, 0x7E, 0x18 , //0xC 0x3F, 0x33, 0x3F, 0x30, 0x30, 0x70, 0xF0, 0xE0 , //0xD 0x7F, 0x63, 0x7F, 0x63, 0x63, 0x67, 0xE6, 0xC0 , //0xE 0x99, 0x5A, 0x3C, 0xE7, 0xE7, 0x3C, 0x5A, 0x99 , //0xF 0x80, 0xE0, 0xF8, 0xFE, 0xF8, 0xE0, 0x80, 0x00 , //0x10 0x02, 0x0E, 0x3E, 0xFE, 0x3E, 0x0E, 0x02, 0x00 , //0x11 0x18, 0x3C, 0x7E, 0x18, 0x18, 0x7E, 0x3C, 0x18 , //0x12 0x66, 0x66, 0x66, 0x66, 0x66, 0x00, 0x66, 0x00 , //0x13 0x7F, 0xDB, 0xDB, 0x7B, 0x1B, 0x1B, 0x1B, 0x00 , //0x14 0x3E, 0x63, 0x38, 0x6C, 0x6C, 0x38, 0xCC, 0x78 , //0x15 0x00, 0x00, 0x00, 0x00, 0x7E, 0x7E, 0x7E, 0x00 , //0x16 0x18, 0x3C, 0x7E, 0x18, 0x7E, 0x3C, 0x18, 0xFF , //0x17 0x18, 0x3C, 0x7E, 0x18, 0x18, 0x18, 0x18, 0x00 , //0x18 0x18, 0x18, 0x18, 0x18, 0x7E, 0x3C, 0x18, 0x00 , //0x19 0x00, 0x18, 0x0C, 0xFE, 0x0C, 0x18, 0x00, 0x00 , //0x1A 0x00, 0x30, 0x60, 0xFE, 0x60, 0x30, 0x00, 0x00 , //0x1B 0x00, 0x00, 0xC0, 0xC0, 0xC0, 0xFE, 0x00, 0x00 , //0x1C 0x00, 0x24, 0x66, 0xFF, 0x66, 0x24, 0x00, 0x00 , //0x1D 0x00, 0x18, 0x3C, 0x7E, 0xFF, 0xFF, 0x00, 0x00 , //0x1E 0x00, 0xFF, 0xFF, 0x7E, 0x3C, 0x18, 0x00, 0x00 , //0x1F 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x20 0x30, 0x78, 0x78, 0x30, 0x30, 0x00, 0x30, 0x00 , //0x21 0x6C, 0x6C, 0x6C, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x22 0x6C, 0x6C, 0xFE, 0x6C, 0xFE, 0x6C, 0x6C, 0x00 , //0x23 0x30, 0x7C, 0xC0, 0x78, 0x0C, 0xF8, 0x30, 0x00 , //0x24 0x00, 0xC6, 0xCC, 0x18, 0x30, 0x66, 0xC6, 0x00 , //0x25 0x38, 0x6C, 0x38, 0x76, 0xDC, 0xCC, 0x76, 0x00 , //0x26 0x60, 0x60, 0xC0, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x27 0x18, 0x30, 0x60, 0x60, 0x60, 0x30, 0x18, 0x00 , //0x28 0x60, 0x30, 0x18, 0x18, 0x18, 0x30, 0x60, 0x00 , //0x29 0x00, 0x66, 0x3C, 0xFF, 0x3C, 0x66, 0x00, 0x00 , //0x2A 0x00, 0x30, 0x30, 0xFC, 0x30, 0x30, 0x00, 0x00 , //0x2B 0x00, 0x00, 0x00, 0x00, 0x00, 0x30, 0x30, 0x60 , //0x2C 0x00, 0x00, 0x00, 0xFC, 0x00, 0x00, 0x00, 0x00 , //0x2D 0x00, 0x00, 0x00, 0x00, 0x00, 0x30, 0x30, 0x00 , //0x2E 0x06, 0x0C, 0x18, 0x30, 0x60, 0xC0, 0x80, 0x00 , //0x2F 0x7C, 0xC6, 0xCE, 0xDE, 0xF6, 0xE6, 0x7C, 0x00 , //0x30 0x30, 0x70, 0x30, 0x30, 0x30, 0x30, 0xFC, 0x00 , //0x31 0x78, 0xCC, 0x0C, 0x38, 0x60, 0xCC, 0xFC, 0x00 , //0x32 0x78, 0xCC, 0x0C, 0x38, 0x0C, 0xCC, 0x78, 0x00 , //0x33 0x1C, 0x3C, 0x6C, 0xCC, 0xFE, 0x0C, 0x1E, 0x00 , //0x34 0xFC, 0xC0, 0xF8, 0x0C, 0x0C, 0xCC, 0x78, 0x00 , //0x35 0x38, 0x60, 0xC0, 0xF8, 0xCC, 0xCC, 0x78, 0x00 , //0x36 0xFC, 0xCC, 0x0C, 0x18, 0x30, 0x30, 0x30, 0x00 , //0x37 0x78, 0xCC, 0xCC, 0x78, 0xCC, 0xCC, 0x78, 0x00 , //0x38 0x78, 0xCC, 0xCC, 0x7C, 0x0C, 0x18, 0x70, 0x00 , //0x39 0x00, 0x30, 0x30, 0x00, 0x00, 0x30, 0x30, 0x00 , //0x3A 0x00, 0x30, 0x30, 0x00, 0x00, 0x30, 0x30, 0x60 , //0x3B 0x18, 0x30, 0x60, 0xC0, 0x60, 0x30, 0x18, 0x00 , //0x3C 0x00, 0x00, 0xFC, 0x00, 0x00, 0xFC, 0x00, 0x00 , //0x3D 0x60, 0x30, 0x18, 0x0C, 0x18, 0x30, 0x60, 0x00 , //0x3E 0x78, 0xCC, 0x0C, 0x18, 0x30, 0x00, 0x30, 0x00 , //0x3F 0x7C, 0xC6, 0xDE, 0xDE, 0xDE, 0xC0, 0x78, 0x00 , //0x40 0x30, 0x78, 0xCC, 0xCC, 0xFC, 0xCC, 0xCC, 0x00 , //0x41 0xFC, 0x66, 0x66, 0x7C, 0x66, 0x66, 0xFC, 0x00 , //0x42 0x3C, 0x66, 0xC0, 0xC0, 0xC0, 0x66, 0x3C, 0x00 , //0x43 0xF8, 0x6C, 0x66, 0x66, 0x66, 0x6C, 0xF8, 0x00 , //0x44 0xFE, 0x62, 0x68, 0x78, 0x68, 0x62, 0xFE, 0x00 , //0x45 0xFE, 0x62, 0x68, 0x78, 0x68, 0x60, 0xF0, 0x00 , //0x46 0x3C, 0x66, 0xC0, 0xC0, 0xCE, 0x66, 0x3E, 0x00 , //0x47 0xCC, 0xCC, 0xCC, 0xFC, 0xCC, 0xCC, 0xCC, 0x00 , //0x48 0x78, 0x30, 0x30, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x49 0x1E, 0x0C, 0x0C, 0x0C, 0xCC, 0xCC, 0x78, 0x00 , //0x4A 0xE6, 0x66, 0x6C, 0x78, 0x6C, 0x66, 0xE6, 0x00 , //0x4B 0xF0, 0x60, 0x60, 0x60, 0x62, 0x66, 0xFE, 0x00 , //0x4C 0xC6, 0xEE, 0xFE, 0xFE, 0xD6, 0xC6, 0xC6, 0x00 , //0x4D 0xC6, 0xE6, 0xF6, 0xDE, 0xCE, 0xC6, 0xC6, 0x00 , //0x4E 0x38, 0x6C, 0xC6, 0xC6, 0xC6, 0x6C, 0x38, 0x00 , //0x4F 0xFC, 0x66, 0x66, 0x7C, 0x60, 0x60, 0xF0, 0x00 , //0x50 0x78, 0xCC, 0xCC, 0xCC, 0xDC, 0x78, 0x1C, 0x00 , //0x51 0xFC, 0x66, 0x66, 0x7C, 0x6C, 0x66, 0xE6, 0x00 , //0x52 0x78, 0xCC, 0xE0, 0x70, 0x1C, 0xCC, 0x78, 0x00 , //0x53 0xFC, 0xB4, 0x30, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x54 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 0xFC, 0x00 , //0x55 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 0x78, 0x30, 0x00 , //0x56 0xC6, 0xC6, 0xC6, 0xD6, 0xFE, 0xEE, 0xC6, 0x00 , //0x57 0xC6, 0xC6, 0x6C, 0x38, 0x38, 0x6C, 0xC6, 0x00 , //0x58 0xCC, 0xCC, 0xCC, 0x78, 0x30, 0x30, 0x78, 0x00 , //0x59 0xFE, 0xC6, 0x8C, 0x18, 0x32, 0x66, 0xFE, 0x00 , //0x5A 0x78, 0x60, 0x60, 0x60, 0x60, 0x60, 0x78, 0x00 , //0x5B 0xC0, 0x60, 0x30, 0x18, 0x0C, 0x06, 0x02, 0x00 , //0x5C 0x78, 0x18, 0x18, 0x18, 0x18, 0x18, 0x78, 0x00 , //0x5D 0x10, 0x38, 0x6C, 0xC6, 0x00, 0x00, 0x00, 0x00 , //0x5E 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF , //0x5F 0x30, 0x30, 0x18, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x60 0x00, 0x00, 0x78, 0x0C, 0x7C, 0xCC, 0x76, 0x00 , //0x61 0xE0, 0x60, 0x60, 0x7C, 0x66, 0x66, 0xDC, 0x00 , //0x62 0x00, 0x00, 0x78, 0xCC, 0xC0, 0xCC, 0x78, 0x00 , //0x63 0x1C, 0x0C, 0x0C, 0x7C, 0xCC, 0xCC, 0x76, 0x00 , //0x64 0x00, 0x00, 0x78, 0xCC, 0xFC, 0xC0, 0x78, 0x00 , //0x65 0x38, 0x6C, 0x60, 0xF0, 0x60, 0x60, 0xF0, 0x00 , //0x66 0x00, 0x00, 0x76, 0xCC, 0xCC, 0x7C, 0x0C, 0xF8 , //0x67 0xE0, 0x60, 0x6C, 0x76, 0x66, 0x66, 0xE6, 0x00 , //0x68 0x30, 0x00, 0x70, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x69 0x0C, 0x00, 0x0C, 0x0C, 0x0C, 0xCC, 0xCC, 0x78 , //0x6A 0xE0, 0x60, 0x66, 0x6C, 0x78, 0x6C, 0xE6, 0x00 , //0x6B 0x70, 0x30, 0x30, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x6C 0x00, 0x00, 0xCC, 0xFE, 0xFE, 0xD6, 0xC6, 0x00 , //0x6D 0x00, 0x00, 0xF8, 0xCC, 0xCC, 0xCC, 0xCC, 0x00 , //0x6E 0x00, 0x00, 0x78, 0xCC, 0xCC, 0xCC, 0x78, 0x00 , //0x6F 0x00, 0x00, 0xDC, 0x66, 0x66, 0x7C, 0x60, 0xF0 , //0x70 0x00, 0x00, 0x76, 0xCC, 0xCC, 0x7C, 0x0C, 0x1E , //0x71 0x00, 0x00, 0xDC, 0x76, 0x66, 0x60, 0xF0, 0x00 , //0x72 0x00, 0x00, 0x7C, 0xC0, 0x78, 0x0C, 0xF8, 0x00 , //0x73 0x10, 0x30, 0x7C, 0x30, 0x30, 0x34, 0x18, 0x00 , //0x74 0x00, 0x00, 0xCC, 0xCC, 0xCC, 0xCC, 0x76, 0x00 , //0x75 0x00, 0x00, 0xCC, 0xCC, 0xCC, 0x78, 0x30, 0x00 , //0x76 0x00, 0x00, 0xC6, 0xD6, 0xFE, 0xFE, 0x6C, 0x00 , //0x77 0x00, 0x00, 0xC6, 0x6C, 0x38, 0x6C, 0xC6, 0x00 , //0x78 0x00, 0x00, 0xCC, 0xCC, 0xCC, 0x7C, 0x0C, 0xF8 , //0x79 0x00, 0x00, 0xFC, 0x98, 0x30, 0x64, 0xFC, 0x00 , //0x7A 0x1C, 0x30, 0x30, 0xE0, 0x30, 0x30, 0x1C, 0x00 , //0x7B 0x18, 0x18, 0x18, 0x00, 0x18, 0x18, 0x18, 0x00 , //0x7C 0xE0, 0x30, 0x30, 0x1C, 0x30, 0x30, 0xE0, 0x00 , //0x7D 0x76, 0xDC, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x7E 0x00, 0x10, 0x38, 0x6C, 0xC6, 0xC6, 0xFE, 0x00 , //0x7F 0x78, 0xCC, 0xC0, 0xCC, 0x78, 0x18, 0x0C, 0x78 , //0x80 0x00, 0xCC, 0x00, 0xCC, 0xCC, 0xCC, 0x7E, 0x00 , //0x81 0x1C, 0x00, 0x78, 0xCC, 0xFC, 0xC0, 0x78, 0x00 , //0x82 0x7E, 0xC3, 0x3C, 0x06, 0x3E, 0x66, 0x3F, 0x00 , //0x83 0xCC, 0x00, 0x78, 0x0C, 0x7C, 0xCC, 0x7E, 0x00 , //0x84 0xE0, 0x00, 0x78, 0x0C, 0x7C, 0xCC, 0x7E, 0x00 , //0x85 0x30, 0x30, 0x78, 0x0C, 0x7C, 0xCC, 0x7E, 0x00 , //0x86 0x00, 0x00, 0x78, 0xC0, 0xC0, 0x78, 0x0C, 0x38 , //0x87 0x7E, 0xC3, 0x3C, 0x66, 0x7E, 0x60, 0x3C, 0x00 , //0x88 0xCC, 0x00, 0x78, 0xCC, 0xFC, 0xC0, 0x78, 0x00 , //0x89 0xE0, 0x00, 0x78, 0xCC, 0xFC, 0xC0, 0x78, 0x00 , //0x8A 0xCC, 0x00, 0x70, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x8B 0x7C, 0xC6, 0x38, 0x18, 0x18, 0x18, 0x3C, 0x00 , //0x8C 0xE0, 0x00, 0x70, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x8D 0xC6, 0x38, 0x6C, 0xC6, 0xFE, 0xC6, 0xC6, 0x00 , //0x8E 0x30, 0x30, 0x00, 0x78, 0xCC, 0xFC, 0xCC, 0x00 , //0x8F 0x1C, 0x00, 0xFC, 0x60, 0x78, 0x60, 0xFC, 0x00 , //0x90 0x00, 0x00, 0x7F, 0x0C, 0x7F, 0xCC, 0x7F, 0x00 , //0x91 0x3E, 0x6C, 0xCC, 0xFE, 0xCC, 0xCC, 0xCE, 0x00 , //0x92 0x78, 0xCC, 0x00, 0x78, 0xCC, 0xCC, 0x78, 0x00 , //0x93 0x00, 0xCC, 0x00, 0x78, 0xCC, 0xCC, 0x78, 0x00 , //0x94 0x00, 0xE0, 0x00, 0x78, 0xCC, 0xCC, 0x78, 0x00 , //0x95 0x78, 0xCC, 0x00, 0xCC, 0xCC, 0xCC, 0x7E, 0x00 , //0x96 0x00, 0xE0, 0x00, 0xCC, 0xCC, 0xCC, 0x7E, 0x00 , //0x97 0x00, 0xCC, 0x00, 0xCC, 0xCC, 0x7C, 0x0C, 0xF8 , //0x98 0xC3, 0x18, 0x3C, 0x66, 0x66, 0x3C, 0x18, 0x00 , //0x99 0xCC, 0x00, 0xCC, 0xCC, 0xCC, 0xCC, 0x78, 0x00 , //0x9A 0x18, 0x18, 0x7E, 0xC0, 0xC0, 0x7E, 0x18, 0x18 , //0x9B 0x38, 0x6C, 0x64, 0xF0, 0x60, 0xE6, 0xFC, 0x00 , //0x9C 0xCC, 0xCC, 0x78, 0xFC, 0x30, 0xFC, 0x30, 0x30 , //0x9D 0xF8, 0xCC, 0xCC, 0xFA, 0xC6, 0xCF, 0xC6, 0xC7 , //0x9E 0x0E, 0x1B, 0x18, 0x3C, 0x18, 0x18, 0xD8, 0x70 , //0x9F 0x1C, 0x00, 0x78, 0x0C, 0x7C, 0xCC, 0x7E, 0x00 , //0xA0 0x38, 0x00, 0x70, 0x30, 0x30, 0x30, 0x78, 0x00 , //0xA1 0x00, 0x1C, 0x00, 0x78, 0xCC, 0xCC, 0x78, 0x00 , //0xA2 0x00, 0x1C, 0x00, 0xCC, 0xCC, 0xCC, 0x7E, 0x00 , //0xA3 0x00, 0xF8, 0x00, 0xF8, 0xCC, 0xCC, 0xCC, 0x00 , //0xA4 0xFC, 0x00, 0xCC, 0xEC, 0xFC, 0xDC, 0xCC, 0x00 , //0xA5 0x3C, 0x6C, 0x6C, 0x3E, 0x00, 0x7E, 0x00, 0x00 , //0xA6 0x38, 0x6C, 0x6C, 0x38, 0x00, 0x7C, 0x00, 0x00 , //0xA7 0x30, 0x00, 0x30, 0x60, 0xC0, 0xCC, 0x78, 0x00 , //0xA8 0x00, 0x00, 0x00, 0xFC, 0xC0, 0xC0, 0x00, 0x00 , //0xA9 0x00, 0x00, 0x00, 0xFC, 0x0C, 0x0C, 0x00, 0x00 , //0xAA 0xC3, 0xC6, 0xCC, 0xDE, 0x33, 0x66, 0xCC, 0x0F , //0xAB 0xC3, 0xC6, 0xCC, 0xDB, 0x37, 0x6F, 0xCF, 0x03 , //0xAC 0x18, 0x18, 0x00, 0x18, 0x18, 0x18, 0x18, 0x00 , //0xAD 0x00, 0x33, 0x66, 0xCC, 0x66, 0x33, 0x00, 0x00 , //0xAE 0x00, 0xCC, 0x66, 0x33, 0x66, 0xCC, 0x00, 0x00 , //0xAF 0x22, 0x88, 0x22, 0x88, 0x22, 0x88, 0x22, 0x88 , //0xB0 0x55, 0xAA, 0x55, 0xAA, 0x55, 0xAA, 0x55, 0xAA , //0xB1 0xDB, 0x77, 0xDB, 0xEE, 0xDB, 0x77, 0xDB, 0xEE , //0xB2 0x18, 0x18, 0x18, 0x18, 0x18, 0x18, 0x18, 0x18 , //0xB3 0x18, 0x18, 0x18, 0x18, 0xF8, 0x18, 0x18, 0x18 , //0xB4 0x18, 0x18, 0xF8, 0x18, 0xF8, 0x18, 0x18, 0x18 , //0xB5 0x36, 0x36, 0x36, 0x36, 0xF6, 0x36, 0x36, 0x36 , //0xB6 0x00, 0x00, 0x00, 0x00, 0xFE, 0x36, 0x36, 0x36 , //0xB7 0x00, 0x00, 0xF8, 0x18, 0xF8, 0x18, 0x18, 0x18 , //0xB8 0x36, 0x36, 0xF6, 0x06, 0xF6, 0x36, 0x36, 0x36 , //0xB9 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36 , //0xBA 0x00, 0x00, 0xFE, 0x06, 0xF6, 0x36, 0x36, 0x36 , //0xBB 0x36, 0x36, 0xF6, 0x06, 0xFE, 0x00, 0x00, 0x00 , //0xBC 0x36, 0x36, 0x36, 0x36, 0xFE, 0x00, 0x00, 0x00 , //0xBD 0x18, 0x18, 0xF8, 0x18, 0xF8, 0x00, 0x00, 0x00 , //0xBE 0x00, 0x00, 0x00, 0x00, 0xF8, 0x18, 0x18, 0x18 , //0xBF 0x18, 0x18, 0x18, 0x18, 0x1F, 0x00, 0x00, 0x00 , //0xC0 0x18, 0x18, 0x18, 0x18, 0xFF, 0x00, 0x00, 0x00 , //0xC1 0x00, 0x00, 0x00, 0x00, 0xFF, 0x18, 0x18, 0x18 , //0xC2 0x18, 0x18, 0x18, 0x18, 0x1F, 0x18, 0x18, 0x18 , //0xC3 0x00, 0x00, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00 , //0xC4 0x18, 0x18, 0x18, 0x18, 0xFF, 0x18, 0x18, 0x18 , //0xC5 0x18, 0x18, 0x1F, 0x18, 0x1F, 0x18, 0x18, 0x18 , //0xC6 0x36, 0x36, 0x36, 0x36, 0x37, 0x36, 0x36, 0x36 , //0xC7 0x36, 0x36, 0x37, 0x30, 0x3F, 0x00, 0x00, 0x00 , //0xC8 0x00, 0x00, 0x3F, 0x30, 0x37, 0x36, 0x36, 0x36 , //0xC9 0x36, 0x36, 0xF7, 0x00, 0xFF, 0x00, 0x00, 0x00 , //0xCA 0x00, 0x00, 0xFF, 0x00, 0xF7, 0x36, 0x36, 0x36 , //0xCB 0x36, 0x36, 0x37, 0x30, 0x37, 0x36, 0x36, 0x36 , //0xCC 0x00, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0x00, 0x00 , //0xCD 0x36, 0x36, 0xF7, 0x00, 0xF7, 0x36, 0x36, 0x36 , //0xCE 0x18, 0x18, 0xFF, 0x00, 0xFF, 0x00, 0x00, 0x00 , //0xCF 0x36, 0x36, 0x36, 0x36, 0xFF, 0x00, 0x00, 0x00 , //0xD0 0x00, 0x00, 0xFF, 0x00, 0xFF, 0x18, 0x18, 0x18 , //0xD1 0x00, 0x00, 0x00, 0x00, 0xFF, 0x36, 0x36, 0x36 , //0xD2 0x36, 0x36, 0x36, 0x36, 0x3F, 0x00, 0x00, 0x00 , //0xD3 0x18, 0x18, 0x1F, 0x18, 0x1F, 0x00, 0x00, 0x00 , //0xD4 0x00, 0x00, 0x1F, 0x18, 0x1F, 0x18, 0x18, 0x18 , //0xD5 0x00, 0x00, 0x00, 0x00, 0x3F, 0x36, 0x36, 0x36 , //0xD6 0x36, 0x36, 0x36, 0x36, 0xFF, 0x36, 0x36, 0x36 , //0xD7 0x18, 0x18, 0xFF, 0x18, 0xFF, 0x18, 0x18, 0x18 , //0xD8 0x18, 0x18, 0x18, 0x18, 0xF8, 0x00, 0x00, 0x00 , //0xD9 0x00, 0x00, 0x00, 0x00, 0x1F, 0x18, 0x18, 0x18 , //0xDA 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF , //0xDB 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF , //0xDC 0xF0, 0xF0, 0xF0, 0xF0, 0xF0, 0xF0, 0xF0, 0xF0 , //0xDD 0x0F, 0x0F, 0x0F, 0x0F, 0x0F, 0x0F, 0x0F, 0x0F , //0xDE 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00 , //0xDF 0x00, 0x00, 0x76, 0xDC, 0xC8, 0xDC, 0x76, 0x00 , //0xE0 0x00, 0x78, 0xCC, 0xF8, 0xCC, 0xF8, 0xC0, 0xC0 , //0xE1 0x00, 0xFC, 0xCC, 0xC0, 0xC0, 0xC0, 0xC0, 0x00 , //0xE2 0x00, 0xFE, 0x6C, 0x6C, 0x6C, 0x6C, 0x6C, 0x00 , //0xE3 0xFC, 0xCC, 0x60, 0x30, 0x60, 0xCC, 0xFC, 0x00 , //0xE4 0x00, 0x00, 0x7E, 0xD8, 0xD8, 0xD8, 0x70, 0x00 , //0xE5 0x00, 0x66, 0x66, 0x66, 0x66, 0x7C, 0x60, 0xC0 , //0xE6 0x00, 0x76, 0xDC, 0x18, 0x18, 0x18, 0x18, 0x00 , //0xE7 0xFC, 0x30, 0x78, 0xCC, 0xCC, 0x78, 0x30, 0xFC , //0xE8 0x38, 0x6C, 0xC6, 0xFE, 0xC6, 0x6C, 0x38, 0x00 , //0xE9 0x38, 0x6C, 0xC6, 0xC6, 0x6C, 0x6C, 0xEE, 0x00 , //0xEA 0x1C, 0x30, 0x18, 0x7C, 0xCC, 0xCC, 0x78, 0x00 , //0xEB 0x00, 0x00, 0x7E, 0xDB, 0xDB, 0x7E, 0x00, 0x00 , //0xEC 0x06, 0x0C, 0x7E, 0xDB, 0xDB, 0x7E, 0x60, 0xC0 , //0xED 0x38, 0x60, 0xC0, 0xF8, 0xC0, 0x60, 0x38, 0x00 , //0xEE 0x78, 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 0x00 , //0xEF 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0x00 , //0xF0 0x30, 0x30, 0xFC, 0x30, 0x30, 0x00, 0xFC, 0x00 , //0xF1 0x60, 0x30, 0x18, 0x30, 0x60, 0x00, 0xFC, 0x00 , //0xF2 0x18, 0x30, 0x60, 0x30, 0x18, 0x00, 0xFC, 0x00 , //0xF3 0x0E, 0x1B, 0x1B, 0x18, 0x18, 0x18, 0x18, 0x18 , //0xF4 0x18, 0x18, 0x18, 0x18, 0x18, 0xD8, 0xD8, 0x70 , //0xF5 0x30, 0x30, 0x00, 0xFC, 0x00, 0x30, 0x30, 0x00 , //0xF6 0x00, 0x76, 0xDC, 0x00, 0x76, 0xDC, 0x00, 0x00 , //0xF7 0x38, 0x6C, 0x6C, 0x38, 0x00, 0x00, 0x00, 0x00 , //0xF8 0x00, 0x00, 0x00, 0x18, 0x18, 0x00, 0x00, 0x00 , //0xF9 0x00, 0x00, 0x00, 0x00, 0x18, 0x00, 0x00, 0x00 , //0xFA 0x0F, 0x0C, 0x0C, 0x0C, 0xEC, 0x6C, 0x3C, 0x1C , //0xFB 0x78, 0x6C, 0x6C, 0x6C, 0x6C, 0x00, 0x00, 0x00 , //0xFC 0x70, 0x18, 0x30, 0x60, 0x78, 0x00, 0x00, 0x00 , //0xFD 0x00, 0x00, 0x3C, 0x3C, 0x3C, 0x3C, 0x00, 0x00 , //0xFE 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 , //0xFF ;
void write_byte(unsigned char data) //最底层的传输一个byte的函数 unsigned char i; digitalWrite(PIN_CS, LOW); for(i=8; i>=1; i--)
digitalWrite(PIN_CLK, LOW); digitalWrite(PIN_DIN, data&0x80); data = data<<1; digitalWrite(PIN_CLK, HIGH);
void write(unsigned char addr, unsigned char data) //传输一行数据函数 digitalWrite(PIN_CS, LOW); write_byte(addr); write_byte(data); digitalWrite(PIN_CS, HIGH);
void init() //初始化芯片 write(0x09, 0x00); write(0x0a, 0x03); write(0x0b, 0x07); write(0x0c, 0x01); write(0x0f, 0x00);
int main() unsigned char i, j;
wiringPiSetup(); pinMode(PIN_DIN, OUTPUT); pinMode(PIN_CS, OUTPUT); pinMode(PIN_CLK, OUTPUT);
init(); while (1)
for(j=0; j<256; j++)
for(i=1; i<9; i++) write(i, disp1[j][i-1]); printf("0x%02X\\n", j); delay(500);
return 0; |
从以下两个图片来看，显示效果良好
3. Linux字符设备驱动
Linux内核模块能更方便快捷地调整内核功能，而无需重新编译内核花费巨大的时间。通过编写字符设备驱动模块，能够使得系统通过/dev以字符设备的方式来写数据到8*8的led矩阵中显示。
| #include <linux/init.h> // 用于标记函数的宏，如_init、__exit #include <linux/module.h> // 将内核模块加载到内核中的核心头文件 #include <linux/device.h> // 支持内核驱动模型的头文件 #include <linux/kernel.h> // 包含内核中的类型、宏和函数 #include <linux/fs.h> // 支持Linux文件系统的头文件 #include <asm/uaccess.h> // 复制到用户用户空间函数需要的头文件 #include <linux/gpio.h> // GPIO #define DEVICE_NAME "matrix" ///< 使用此值，设备将会展示在/dev/matrix #define CLASS_NAME "mat" ///< 设备类名，这是一个字符设备驱动
MODULE_LICENSE("GPL"); ///< 许可类型，这回影响到可用功能 MODULE_VERSION("0.1"); ///< 告知用户的版本号
static int majorNumber; ///< 保存主设备号，这里自动确定 static char message[256] = 0; ///< 用于保存从用户空间传输过来字符串的内存 static short size_of_message; ///< 用于记录保存的字符串长度 static int numberOpens = 0; ///< 用于保存设备打开次数的计数器 static struct class* matClass = NULL; ///< 设备驱动类结构体指针 static struct device* matDevice = NULL; ///< 设备驱动设备结构体指针
// 字符设备操作的函数原型，必须在结构体定义前定义 static int dev_open(struct inode *, struct file *); static int dev_release(struct inode *, struct file *); static ssize_t dev_read(struct file *, char *, size_t, loff_t *); static ssize_t dev_write(struct file *, const char *, size_t, loff_t *);
/** @brief 设备在内核中被表示为文件结构。 /linux/fs.h中定义的file_operations结构体， * 它使用C99语法的结构体，列举了文件操作关联的回调函数。 * 字符设备通常需要实现open、read、write和release函数。 */ static struct file_operations fops = .open = dev_open, .read = dev_read, .write = dev_write, .release = dev_release, ;
/** @brief 可加载内核模块初始化函数 * static关键字限制该函数的可见性在该C文件之内。 The __init * __init宏对于内置驱动（非可加载内核模块）来说，只在初始化时调用，在此之后，该函数将被废弃，内存将被回收。 * @return 如果成功返回0 */ static int __init matrix_init(void) printk(KERN_INFO "Initializing matrix.\\n");
// 尝试为这个设备动态生成一个主设备号，虽然麻烦一点，但这是值得的 majorNumber = register_chrdev(0, DEVICE_NAME, &fops); if (majorNumber<0) printk(KERN_ALERT "Failed to register a major number.\\n"); return majorNumber;
// printk(KERN_INFO "EBBChar: registered correctly with major number %d\\n", majorNumber);
// 注册设备类 matClass = class_create(THIS_MODULE, CLASS_NAME); if (IS_ERR(matClass)) // 如果有错误，清理环境 unregister_chrdev(majorNumber, DEVICE_NAME); printk(KERN_ALERT "Failed to register device class.\\n"); return PTR_ERR(matClass); // 对于指针类型返回错误消息正确的方式
// printk(KERN_INFO "EBBChar: device class registered correctly\\n");
// 注册设备驱动 matDevice = device_create(matClass, NULL, MKDEV(majorNumber, 0), NULL, DEVICE_NAME); if (IS_ERR(matDevice)) // 如果有错误，清理环境 class_destroy(matClass); // 重复的代码，可选方式是使用goto语句 unregister_chrdev(majorNumber, DEVICE_NAME); printk(KERN_ALERT "Failed to create the device.\\n"); return PTR_ERR(matDevice);
// printk(KERN_INFO "EBBChar: device class created correctly\\n"); // 搞定，设备已经初始化 return 0;
/** @brief 可加载内核模块清理函数 * 和初始化函数类似，该函数是静态的。__exit宏标识如果这个代码是使用在内置驱动（非可加载内核模块）中，该函数不需要。 */ static void __exit matrix_exit(void) device_destroy(matClass, MKDEV(majorNumber, 0)); // 移除设备 class_unregister(matClass); // 注销设备类 class_destroy(matClass); // 移除设备类 unregister_chrdev(majorNumber, DEVICE_NAME); // 注销主设备号 printk(KERN_INFO "Goodbye!\\n");
static unsigned PIN_DIN = 23; static unsigned PIN_CS = 24; static unsigned PIN_CLK = 25;
static unsigned char disp1[256][8] = 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x0 0x7E, 0x81, 0xA5, 0x81, 0xBD, 0x99, 0x81, 0x7E , //0x1 0x7E, 0xFF, 0xDB, 0xFF, 0xC3, 0xE7, 0xFF, 0x7E , //0x2 0x6C, 0xFE, 0xFE, 0xFE, 0x7C, 0x38, 0x10, 0x00 , //0x3 0x10, 0x38, 0x7C, 0xFE, 0x7C, 0x38, 0x10, 0x00 , //0x4 0x38, 0x7C, 0x38, 0xFE, 0xFE, 0x7C, 0x38, 0x7C , //0x5 0x10, 0x10, 0x38, 0x7C, 0xFE, 0x7C, 0x38, 0x7C , //0x6 0x00, 0x00, 0x18, 0x3C, 0x3C, 0x18, 0x00, 0x00 , //0x7 0xFF, 0xFF, 0xE7, 0xC3, 0xC3, 0xE7, 0xFF, 0xFF , //0x8 0x00, 0x3C, 0x66, 0x42, 0x42, 0x66, 0x3C, 0x00 , //0x9 0xFF, 0xC3, 0x99, 0xBD, 0xBD, 0x99, 0xC3, 0xFF , //0xA 0x0F, 0x07, 0x0F, 0x7D, 0xCC, 0xCC, 0xCC, 0x78 , //0xB 0x3C, 0x66, 0x66, 0x66, 0x3C, 0x18, 0x7E, 0x18 , //0xC 0x3F, 0x33, 0x3F, 0x30, 0x30, 0x70, 0xF0, 0xE0 , //0xD 0x7F, 0x63, 0x7F, 0x63, 0x63, 0x67, 0xE6, 0xC0 , //0xE 0x99, 0x5A, 0x3C, 0xE7, 0xE7, 0x3C, 0x5A, 0x99 , //0xF 0x80, 0xE0, 0xF8, 0xFE, 0xF8, 0xE0, 0x80, 0x00 , //0x10 0x02, 0x0E, 0x3E, 0xFE, 0x3E, 0x0E, 0x02, 0x00 , //0x11 0x18, 0x3C, 0x7E, 0x18, 0x18, 0x7E, 0x3C, 0x18 , //0x12 0x66, 0x66, 0x66, 0x66, 0x66, 0x00, 0x66, 0x00 , //0x13 0x7F, 0xDB, 0xDB, 0x7B, 0x1B, 0x1B, 0x1B, 0x00 , //0x14 0x3E, 0x63, 0x38, 0x6C, 0x6C, 0x38, 0xCC, 0x78 , //0x15 0x00, 0x00, 0x00, 0x00, 0x7E, 0x7E, 0x7E, 0x00 , //0x16 0x18, 0x3C, 0x7E, 0x18, 0x7E, 0x3C, 0x18, 0xFF , //0x17 0x18, 0x3C, 0x7E, 0x18, 0x18, 0x18, 0x18, 0x00 , //0x18 0x18, 0x18, 0x18, 0x18, 0x7E, 0x3C, 0x18, 0x00 , //0x19 0x00, 0x18, 0x0C, 0xFE, 0x0C, 0x18, 0x00, 0x00 , //0x1A 0x00, 0x30, 0x60, 0xFE, 0x60, 0x30, 0x00, 0x00 , //0x1B 0x00, 0x00, 0xC0, 0xC0, 0xC0, 0xFE, 0x00, 0x00 , //0x1C 0x00, 0x24, 0x66, 0xFF, 0x66, 0x24, 0x00, 0x00 , //0x1D 0x00, 0x18, 0x3C, 0x7E, 0xFF, 0xFF, 0x00, 0x00 , //0x1E 0x00, 0xFF, 0xFF, 0x7E, 0x3C, 0x18, 0x00, 0x00 , //0x1F 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x20 0x30, 0x78, 0x78, 0x30, 0x30, 0x00, 0x30, 0x00 , //0x21 0x6C, 0x6C, 0x6C, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x22 0x6C, 0x6C, 0xFE, 0x6C, 0xFE, 0x6C, 0x6C, 0x00 , //0x23 0x30, 0x7C, 0xC0, 0x78, 0x0C, 0xF8, 0x30, 0x00 , //0x24 0x00, 0xC6, 0xCC, 0x18, 0x30, 0x66, 0xC6, 0x00 , //0x25 0x38, 0x6C, 0x38, 0x76, 0xDC, 0xCC, 0x76, 0x00 , //0x26 0x60, 0x60, 0xC0, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x27 0x18, 0x30, 0x60, 0x60, 0x60, 0x30, 0x18, 0x00 , //0x28 0x60, 0x30, 0x18, 0x18, 0x18, 0x30, 0x60, 0x00 , //0x29 0x00, 0x66, 0x3C, 0xFF, 0x3C, 0x66, 0x00, 0x00 , //0x2A 0x00, 0x30, 0x30, 0xFC, 0x30, 0x30, 0x00, 0x00 , //0x2B 0x00, 0x00, 0x00, 0x00, 0x00, 0x30, 0x30, 0x60 , //0x2C 0x00, 0x00, 0x00, 0xFC, 0x00, 0x00, 0x00, 0x00 , //0x2D 0x00, 0x00, 0x00, 0x00, 0x00, 0x30, 0x30, 0x00 , //0x2E 0x06, 0x0C, 0x18, 0x30, 0x60, 0xC0, 0x80, 0x00 , //0x2F 0x7C, 0xC6, 0xCE, 0xDE, 0xF6, 0xE6, 0x7C, 0x00 , //0x30 0x30, 0x70, 0x30, 0x30, 0x30, 0x30, 0xFC, 0x00 , //0x31 0x78, 0xCC, 0x0C, 0x38, 0x60, 0xCC, 0xFC, 0x00 , //0x32 0x78, 0xCC, 0x0C, 0x38, 0x0C, 0xCC, 0x78, 0x00 , //0x33 0x1C, 0x3C, 0x6C, 0xCC, 0xFE, 0x0C, 0x1E, 0x00 , //0x34 0xFC, 0xC0, 0xF8, 0x0C, 0x0C, 0xCC, 0x78, 0x00 , //0x35 0x38, 0x60, 0xC0, 0xF8, 0xCC, 0xCC, 0x78, 0x00 , //0x36 0xFC, 0xCC, 0x0C, 0x18, 0x30, 0x30, 0x30, 0x00 , //0x37 0x78, 0xCC, 0xCC, 0x78, 0xCC, 0xCC, 0x78, 0x00 , //0x38 0x78, 0xCC, 0xCC, 0x7C, 0x0C, 0x18, 0x70, 0x00 , //0x39 0x00, 0x30, 0x30, 0x00, 0x00, 0x30, 0x30, 0x00 , //0x3A 0x00, 0x30, 0x30, 0x00, 0x00, 0x30, 0x30, 0x60 , //0x3B 0x18, 0x30, 0x60, 0xC0, 0x60, 0x30, 0x18, 0x00 , //0x3C 0x00, 0x00, 0xFC, 0x00, 0x00, 0xFC, 0x00, 0x00 , //0x3D 0x60, 0x30, 0x18, 0x0C, 0x18, 0x30, 0x60, 0x00 , //0x3E 0x78, 0xCC, 0x0C, 0x18, 0x30, 0x00, 0x30, 0x00 , //0x3F 0x7C, 0xC6, 0xDE, 0xDE, 0xDE, 0xC0, 0x78, 0x00 , //0x40 0x30, 0x78, 0xCC, 0xCC, 0xFC, 0xCC, 0xCC, 0x00 , //0x41 0xFC, 0x66, 0x66, 0x7C, 0x66, 0x66, 0xFC, 0x00 , //0x42 0x3C, 0x66, 0xC0, 0xC0, 0xC0, 0x66, 0x3C, 0x00 , //0x43 0xF8, 0x6C, 0x66, 0x66, 0x66, 0x6C, 0xF8, 0x00 , //0x44 0xFE, 0x62, 0x68, 0x78, 0x68, 0x62, 0xFE, 0x00 , //0x45 0xFE, 0x62, 0x68, 0x78, 0x68, 0x60, 0xF0, 0x00 , //0x46 0x3C, 0x66, 0xC0, 0xC0, 0xCE, 0x66, 0x3E, 0x00 , //0x47 0xCC, 0xCC, 0xCC, 0xFC, 0xCC, 0xCC, 0xCC, 0x00 , //0x48 0x78, 0x30, 0x30, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x49 0x1E, 0x0C, 0x0C, 0x0C, 0xCC, 0xCC, 0x78, 0x00 , //0x4A 0xE6, 0x66, 0x6C, 0x78, 0x6C, 0x66, 0xE6, 0x00 , //0x4B 0xF0, 0x60, 0x60, 0x60, 0x62, 0x66, 0xFE, 0x00 , //0x4C 0xC6, 0xEE, 0xFE, 0xFE, 0xD6, 0xC6, 0xC6, 0x00 , //0x4D 0xC6, 0xE6, 0xF6, 0xDE, 0xCE, 0xC6, 0xC6, 0x00 , //0x4E 0x38, 0x6C, 0xC6, 0xC6, 0xC6, 0x6C, 0x38, 0x00 , //0x4F 0xFC, 0x66, 0x66, 0x7C, 0x60, 0x60, 0xF0, 0x00 , //0x50 0x78, 0xCC, 0xCC, 0xCC, 0xDC, 0x78, 0x1C, 0x00 , //0x51 0xFC, 0x66, 0x66, 0x7C, 0x6C, 0x66, 0xE6, 0x00 , //0x52 0x78, 0xCC, 0xE0, 0x70, 0x1C, 0xCC, 0x78, 0x00 , //0x53 0xFC, 0xB4, 0x30, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x54 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 0xFC, 0x00 , //0x55 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 0x78, 0x30, 0x00 , //0x56 0xC6, 0xC6, 0xC6, 0xD6, 0xFE, 0xEE, 0xC6, 0x00 , //0x57 0xC6, 0xC6, 0x6C, 0x38, 0x38, 0x6C, 0xC6, 0x00 , //0x58 0xCC, 0xCC, 0xCC, 0x78, 0x30, 0x30, 0x78, 0x00 , //0x59 0xFE, 0xC6, 0x8C, 0x18, 0x32, 0x66, 0xFE, 0x00 , //0x5A 0x78, 0x60, 0x60, 0x60, 0x60, 0x60, 0x78, 0x00 , //0x5B 0xC0, 0x60, 0x30, 0x18, 0x0C, 0x06, 0x02, 0x00 , //0x5C 0x78, 0x18, 0x18, 0x18, 0x18, 0x18, 0x78, 0x00 , //0x5D 0x10, 0x38, 0x6C, 0xC6, 0x00, 0x00, 0x00, 0x00 , //0x5E 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF , //0x5F 0x30, 0x30, 0x18, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x60 0x00, 0x00, 0x78, 0x0C, 0x7C, 0xCC, 0x76, 0x00 , //0x61 0xE0, 0x60, 0x60, 0x7C, 0x66, 0x66, 0xDC, 0x00 , //0x62 0x00, 0x00, 0x78, 0xCC, 0xC0, 0xCC, 0x78, 0x00 , //0x63 0x1C, 0x0C, 0x0C, 0x7C, 0xCC, 0xCC, 0x76, 0x00 , //0x64 0x00, 0x00, 0x78, 0xCC, 0xFC, 0xC0, 0x78, 0x00 , //0x65 0x38, 0x6C, 0x60, 0xF0, 0x60, 0x60, 0xF0, 0x00 , //0x66 0x00, 0x00, 0x76, 0xCC, 0xCC, 0x7C, 0x0C, 0xF8 , //0x67 0xE0, 0x60, 0x6C, 0x76, 0x66, 0x66, 0xE6, 0x00 , //0x68 0x30, 0x00, 0x70, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x69 0x0C, 0x00, 0x0C, 0x0C, 0x0C, 0xCC, 0xCC, 0x78 , //0x6A 0xE0, 0x60, 0x66, 0x6C, 0x78, 0x6C, 0xE6, 0x00 , //0x6B 0x70, 0x30, 0x30, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x6C 0x00, 0x00, 0xCC, 0xFE, 0xFE, 0xD6, 0xC6, 0x00 , //0x6D 0x00, 0x00, 0xF8, 0xCC, 0xCC, 0xCC, 0xCC, 0x00 , //0x6E 0x00, 0x00, 0x78, 0xCC, 0xCC, 0xCC, 0x78, 0x00 , //0x6F 0x00, 0x00, 0xDC, 0x66, 0x66, 0x7C, 0x60, 0xF0 , //0x70 0x00, 0x00, 0x76, 0xCC, 0xCC, 0x7C, 0x0C, 0x1E , //0x71 0x00, 0x00, 0xDC, 0x76, 0x66, 0x60, 0xF0, 0x00 , //0x72 0x00, 0x00, 0x7C, 0xC0, 0x78, 0x0C, 0xF8, 0x00 , //0x73 0x10, 0x30, 0x7C, 0x30, 0x30, 0x34, 0x18, 0x00 , //0x74 0x00, 0x00, 0xCC, 0xCC, 0xCC, 0xCC, 0x76, 0x00 , //0x75 0x00, 0x00, 0xCC, 0xCC, 0xCC, 0x78, 0x30, 0x00 , //0x76 0x00, 0x00, 0xC6, 0xD6, 0xFE, 0xFE, 0x6C, 0x00 , //0x77 0x00, 0x00, 0xC6, 0x6C, 0x38, 0x6C, 0xC6, 0x00 , //0x78 0x00, 0x00, 0xCC, 0xCC, 0xCC, 0x7C, 0x0C, 0xF8 , //0x79 0x00, 0x00, 0xFC, 0x98, 0x30, 0x64, 0xFC, 0x00 , //0x7A 0x1C, 0x30, 0x30, 0xE0, 0x30, 0x30, 0x1C, 0x00 , //0x7B 0x18, 0x18, 0x18, 0x00, 0x18, 0x18, 0x18, 0x00 , //0x7C 0xE0, 0x30, 0x30, 0x1C, 0x30, 0x30, 0xE0, 0x00 , //0x7D 0x76, 0xDC, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 , //0x7E 0x00, 0x10, 0x38, 0x6C, 0xC6, 0xC6, 0xFE, 0x00 , //0x7F 0x78, 0xCC, 0xC0, 0xCC, 0x78, 0x18, 0x0C, 0x78 , //0x80 0x00, 0xCC, 0x00, 0xCC, 0xCC, 0xCC, 0x7E, 0x00 , //0x81 0x1C, 0x00, 0x78, 0xCC, 0xFC, 0xC0, 0x78, 0x00 , //0x82 0x7E, 0xC3, 0x3C, 0x06, 0x3E, 0x66, 0x3F, 0x00 , //0x83 0xCC, 0x00, 0x78, 0x0C, 0x7C, 0xCC, 0x7E, 0x00 , //0x84 0xE0, 0x00, 0x78, 0x0C, 0x7C, 0xCC, 0x7E, 0x00 , //0x85 0x30, 0x30, 0x78, 0x0C, 0x7C, 0xCC, 0x7E, 0x00 , //0x86 0x00, 0x00, 0x78, 0xC0, 0xC0, 0x78, 0x0C, 0x38 , //0x87 0x7E, 0xC3, 0x3C, 0x66, 0x7E, 0x60, 0x3C, 0x00 , //0x88 0xCC, 0x00, 0x78, 0xCC, 0xFC, 0xC0, 0x78, 0x00 , //0x89 0xE0, 0x00, 0x78, 0xCC, 0xFC, 0xC0, 0x78, 0x00 , //0x8A 0xCC, 0x00, 0x70, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x8B 0x7C, 0xC6, 0x38, 0x18, 0x18, 0x18, 0x3C, 0x00 , //0x8C 0xE0, 0x00, 0x70, 0x30, 0x30, 0x30, 0x78, 0x00 , //0x8D 0xC6, 0x38, 0x6C, 0xC6, 0xFE, 0xC6, 0xC6, 0x00 , //0x8E 0x30, 0x30, 0x00, 0x78, 0xCC, 0xFC, 0xCC, 0x00 , //0x8F 0x1C, 0x00, 0xFC, 0x60, 0x78, 0x60, 0xFC, 0x00 , //0x90 0x00, 0x00, 0x7F, 0x0C, 0x7F, 0xCC, 0x7F, 0x00 , //0x91 0x3E, 0x6C, 0xCC, 0xFE, 0xCC, 0xCC, 0xCE, 0x00 , //0x92 0x78, 0xCC, 0x00, 0x78, 0xCC, 0xCC, 0x78, 0x00 , //0x93 0x00, 0xCC, 0x00, 0x78, 0xCC, 0xCC, 0x78, 0x00 , //0x94 0x00, 0xE0, 0x00, 0x78, 0xCC, 0xCC, 0x78, 0x00 , //0x95 0x78, 0xCC, 0x00, 0xCC, 0xCC, 0xCC, 0x7E, 0x00 , //0x96 0x00, 0xE0, 0x00, 0xCC, 0xCC, 0xCC, 0x7E, 0x00 , //0x97 0x00, 0xCC, 0x00, 0xCC, 0xCC, 0x7C, 0x0C, 0xF8 , //0x98 0xC3, 0x18, 0x3C, 0x66, 0x66, 0x3C, 0x18, 0x00 , //0x99 0xCC, 0x00, 0xCC, 0xCC, 0xCC, 0xCC, 0x78, 0x00 , //0x9A 0x18, 0x18, 0x7E, 0xC0, 0xC0, 0x7E, 0x18, 0x18 , //0x9B 0x38, 0x6C, 0x64, 0xF0, 0x60, 0xE6, 0xFC, 0x00 , //0x9C 0xCC, 0xCC, 0x78, 0xFC, 0x30, 0xFC, 0x30, 0x30 , //0x9D 0xF8, 0xCC, 0xCC, 0xFA, 0xC6, 0xCF, 0xC6, 0xC7 , //0x9E 0x0E, 0x1B, 0x18, 0x3C, 0x18, 0x18, 0xD8, 0x70 , //0x9F 0x1C, 0x00, 0x78, 0x0C, 0x7C, 0xCC, 0x7E, 0x00 , //0xA0 0x38, 0x00, 0x70, 0x30, 0x30, 0x30, 0x78, 0x00 , //0xA1 0x00, 0x1C, 0x00, 0x78, 0xCC, 0xCC, 0x78, 0x00 , //0xA2 0x00, 0x1C, 0x00, 0xCC, 0xCC, 0xCC, 0x7E, 0x00 , //0xA3 0x00, 0xF8, 0x00, 0xF8, 0xCC, 0xCC, 0xCC, 0x00 , //0xA4 0xFC, 0x00, 0xCC, 0xEC, 0xFC, 0xDC, 0xCC, 0x00 , //0xA5 0x3C, 0x6C, 0x6C, 0x3E, 0x00, 0x7E, 0x00, 0x00 , //0xA6 0x38, 0x6C, 0x6C, 0x38, 0x00, 0x7C, 0x00, 0x00 , //0xA7 0x30, 0x00, 0x30, 0x60, 0xC0, 0xCC, 0x78, 0x00 , //0xA8 0x00, 0x00, 0x00, 0xFC, 0xC0, 0xC0, 0x00, 0x00 , //0xA9 0x00, 0x00, 0x00, 0xFC, 0x0C, 0x0C, 0x00, 0x00 , //0xAA 0xC3, 0xC6, 0xCC, 0xDE, 0x33, 0x66, 0xCC, 0x0F , //0xAB 0xC3, 0xC6, 0xCC, 0xDB, 0x37, 0x6F, 0xCF, 0x03 , //0xAC 0x18, 0x18, 0x00, 0x18, 0x18, 0x18, 0x18, 0x00 , //0xAD 0x00, 0x33, 0x66, 0xCC, 0x66, 0x33, 0x00, 0x00 , //0xAE 0x00, 0xCC, 0x66, 0x33, 0x66, 0xCC, 0x00, 0x00 , //0xAF 0x22, 0x88, 0x22, 0x88, 0x22, 0x88, 0x22, 0x88 , //0xB0 0x55, 0xAA, 0x55, 0xAA, 0x55, 0xAA, 0x55, 0xAA , //0xB1 0xDB, 0x77, 0xDB, 0xEE, 0xDB, 0x77, 0xDB, 0xEE , //0xB2 0x18, 0x18, 0x18, 0x18, 0x18, 0x18, 0x18, 0x18 , //0xB3 0x18, 0x18, 0x18, 0x18, 0xF8, 0x18, 0x18, 0x18 , //0xB4 0x18, 0x18, 0xF8, 0x18, 0xF8, 0x18, 0x18, 0x18 , //0xB5 0x36, 0x36, 0x36, 0x36, 0xF6, 0x36, 0x36, 0x36 , //0xB6 0x00, 0x00, 0x00, 0x00, 0xFE, 0x36, 0x36, 0x36 , //0xB7 0x00, 0x00, 0xF8, 0x18, 0xF8, 0x18, 0x18, 0x18 , //0xB8 0x36, 0x36, 0xF6, 0x06, 0xF6, 0x36, 0x36, 0x36 , //0xB9 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36 , //0xBA 0x00, 0x00, 0xFE, 0x06, 0xF6, 0x36, 0x36, 0x36 , //0xBB 0x36, 0x36, 0xF6, 0x06, 0xFE, 0x00, 0x00, 0x00 , //0xBC 0x36, 0x36, 0x36, 0x36, 0xFE, 0x00, 0x00, 0x00 , //0xBD 0x18, 0x18, 0xF8, 0x18, 0xF8, 0x00, 0x00, 0x00 , //0xBE 0x00, 0x00, 0x00, 0x00, 0xF8, 0x18, 0x18, 0x18 , //0xBF 0x18, 0x18, 0x18, 0x18, 0x1F, 0x00, 0x00, 0x00 , //0xC0 0x18, 0x18, 0x18, 0x18, 0xFF, 0x00, 0x00, 0x00 , //0xC1 0x00, 0x00, 0x00, 0x00, 0xFF, 0x18, 0x18, 0x18 , //0xC2 0x18, 0x18, 0x18, 0x18, 0x1F, 0x18, 0x18, 0x18 , //0xC3 0x00, 0x00, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00 , //0xC4 0x18, 0x18, 0x18, 0x18, 0xFF, 0x18, 0x18, 0x18 , //0xC5 0x18, 0x18, 0x1F, 0x18, 0x1F, 0x18, 0x18, 0x18 , //0xC6 0x36, 0x36, 0x36, 0x36, 0x37, 0x36, 0x36, 0x36 , //0xC7 0x36, 0x36, 0x37, 0x30, 0x3F, 0x00, 0x00, 0x00 , //0xC8 0x00, 0x00, 0x3F, 0x30, 0x37, 0x36, 0x36, 0x36 , //0xC9 0x36, 0x36, 0xF7, 0x00, 0xFF, 0x00, 0x00, 0x00 , //0xCA 0x00, 0x00, 0xFF, 0x00, 0xF7, 0x36, 0x36, 0x36 , //0xCB 0x36, 0x36, 0x37, 0x30, 0x37, 0x36, 0x36, 0x36 , //0xCC 0x00, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0x00, 0x00 , //0xCD 0x36, 0x36, 0xF7, 0x00, 0xF7, 0x36, 0x36, 0x36 , //0xCE 0x18, 0x18, 0xFF, 0x00, 0xFF, 0x00, 0x00, 0x00 , //0xCF 0x36, 0x36, 0x36, 0x36, 0xFF, 0x00, 0x00, 0x00 , //0xD0 0x00, 0x00, 0xFF, 0x00, 0xFF, 0x18, 0x18, 0x18 , //0xD1 0x00, 0x00, 0x00, 0x00, 0xFF, 0x36, 0x36, 0x36 , //0xD2 0x36, 0x36, 0x36, 0x36, 0x3F, 0x00, 0x00, 0x00 , //0xD3 0x18, 0x18, 0x1F, 0x18, 0x1F, 0x00, 0x00, 0x00 , //0xD4 0x00, 0x00, 0x1F, 0x18, 0x1F, 0x18, 0x18, 0x18 , //0xD5 0x00, 0x00, 0x00, 0x00, 0x3F, 0x36, 0x36, 0x36 , //0xD6 0x36, 0x36, 0x36, 0x36, 0xFF, 0x36, 0x36, 0x36 , //0xD7 0x18, 0x18, 0xFF, 0x18, 0xFF, 0x18, 0x18, 0x18 , //0xD8 0x18, 0x18, 0x18, 0x18, 0xF8, 0x00, 0x00, 0x00 , //0xD9 0x00, 0x00, 0x00, 0x00, 0x1F, 0x18, 0x18, 0x18 , //0xDA 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF , //0xDB 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF , //0xDC 0xF0, 0xF0, 0xF0, 0xF0, 0xF0, 0xF0, 0xF0, 0xF0 , //0xDD 0x0F, 0x0F, 0x0F, 0x0F, 0x0F, 0x0F, 0x0F, 0x0F , //0xDE 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00 , //0xDF 0x00, 0x00, 0x76, 0xDC, 0xC8, 0xDC, 0x76, 0x00 , //0xE0 0x00, 0x78, 0xCC, 0xF8, 0xCC, 0xF8, 0xC0, 0xC0 , //0xE1 0x00, 0xFC, 0xCC, 0xC0, 0xC0, 0xC0, 0xC0, 0x00 , //0xE2 0x00, 0xFE, 0x6C, 0x6C, 0x6C, 0x6C, 0x6C, 0x00 , //0xE3 0xFC, 0xCC, 0x60, 0x30, 0x60, 0xCC, 0xFC, 0x00 , //0xE4 0x00, 0x00, 0x7E, 0xD8, 0xD8, 0xD8, 0x70, 0x00 , //0xE5 0x00, 0x66, 0x66, 0x66, 0x66, 0x7C, 0x60, 0xC0 , //0xE6 0x00, 0x76, 0xDC, 0x18, 0x18, 0x18, 0x18, 0x00 , //0xE7 0xFC, 0x30, 0x78, 0xCC, 0xCC, 0x78, 0x30, 0xFC , //0xE8 0x38, 0x6C, 0xC6, 0xFE, 0xC6, 0x6C, 0x38, 0x00 , //0xE9 0x38, 0x6C, 0xC6, 0xC6, 0x6C, 0x6C, 0xEE, 0x00 , //0xEA 0x1C, 0x30, 0x18, 0x7C, 0xCC, 0xCC, 0x78, 0x00 , //0xEB 0x00, 0x00, 0x7E, 0xDB, 0xDB, 0x7E, 0x00, 0x00 , //0xEC 0x06, 0x0C, 0x7E, 0xDB, 0xDB, 0x7E, 0x60, 0xC0 , //0xED 0x38, 0x60, 0xC0, 0xF8, 0xC0, 0x60, 0x38, 0x00 , //0xEE 0x78, 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 0xCC, 0x00 , //0xEF 0x00, 0xFC, 0x00, 0xFC, 0x00, 0xFC, 0x00, 0x00 , //0xF0 0x30, 0x30, 0xFC, 0x30, 0x30, 0x00, 0xFC, 0x00 , //0xF1 0x60, 0x30, 0x18, 0x30, 0x60, 0x00, 0xFC, 0x00 , //0xF2 0x18, 0x30, 0x60, 0x30, 0x18, 0x00, 0xFC, 0x00 , //0xF3 0x0E, 0x1B, 0x1B, 0x18, 0x18, 0x18, 0x18, 0x18 , //0xF4 0x18, 0x18, 0x18, 0x18, 0x18, 0xD8, 0xD8, 0x70 , //0xF5 0x30, 0x30, 0x00, 0xFC, 0x00, 0x30, 0x30, 0x00 , //0xF6 0x00, 0x76, 0xDC, 0x00, 0x76, 0xDC, 0x00, 0x00 , //0xF7 0x38, 0x6C, 0x6C, 0x38, 0x00, 0x00, 0x00, 0x00 , //0xF8 0x00, 0x00, 0x00, 0x18, 0x18, 0x00, 0x00, 0x00 , //0xF9 0x00, 0x00, 0x00, 0x00, 0x18, 0x00, 0x00, 0x00 , //0xFA 0x0F, 0x0C, 0x0C, 0x0C, 0xEC, 0x6C, 0x3C, 0x1C , //0xFB 0x78, 0x6C, 0x6C, 0x6C, 0x6C, 0x00, 0x00, 0x00 , //0xFC 0x70, 0x18, 0x30, 0x60, 0x78, 0x00, 0x00, 0x00 , //0xFD 0x00, 0x00, 0x3C, 0x3C, 0x3C, 0x3C, 0x00, 0x00 , //0xFE 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 , //0xFF ;
static void writeMatrix_byte(unsigned char data) unsigned char i; gpio_set_value(PIN_CS, 0); for(i=8; i>=1; i--)
gpio_set_value(PIN_CLK, 0); gpio_set_value(PIN_DIN, data&0x80); data = data<<1; gpio_set_value(PIN_CLK, 1);
static void writeMatrix(unsigned char addr, unsigned char data) gpio_set_value(PIN_CS, 0); writeMatrix_byte(addr); writeMatrix_byte(data); gpio_set_value(PIN_CS, 1);
/** @brief 每次设备被代开的时候调用的设备打开函数 * 在本例中，该函数只是简单的累加numberOpens计数器。 * @param inodep 指向inode对象的指针（定义在linux/fs.h头文件中） * @param filep 指向文件对象指针（定义在linux/fs.h头文件中） */ static int dev_open(struct inode *inodep, struct file *filep) int req_din = gpio_request(PIN_DIN, "PIN_DIN"); int req_cs = gpio_request(PIN_CS, "PIN_CS"); int req_clk = gpio_request(PIN_CLK, "PIN_CLK");
if (req_din || req_cs || req_clk) return -1;
gpio_direction_output(PIN_DIN, 0); gpio_direction_output(PIN_CS, 0); gpio_direction_output(PIN_CLK, 0);
numberOpens++; printk(KERN_INFO "Device has been opened %d time(s)\\n", numberOpens);
writeMatrix(0x09, 0x00); writeMatrix(0x0a, 0x03); writeMatrix(0x0b, 0x07); writeMatrix(0x0c, 0x01); writeMatrix(0x0f, 0x00); return 0;
/** @brief 该函数在设备从用户空间读取的时候被调用，即数据从设备向用户空间传输。 * 在本例中，通过copy_to_user()函数将缓冲区中的字符串发送给用户，并且捕获任何异常。 * @param filep 指向文件对象的指针（定义在linux/fs.h头文件中） * @param buffer 指向本函数写入数据的缓冲区指针 * @param len 缓冲区长度 * @param offset 此次读取在内核缓冲区中的偏移量 */ static ssize_t dev_read(struct file *filep, char *buffer, size_t len, loff_t *offset) return 0;
/** @brief 该函数在设备想用户空间写入的时候调用，即从数据从用户发往设备。 * 在此内核模块中，数据通过sprintf()函数复制到message[]数组中，同时字符串长度被保存到size_of_message变量中。 * @param filep 指向文件对象的指针 * @param buffer 包含待写入设备字符串的缓冲区 * @param len 传递到const char类型缓冲区的数据长度 * @param offset 文件设备当前偏移量 */ static ssize_t dev_write(struct file *filep, const char *buffer, size_t len, loff_t *offset) //sprintf(message, "%s(%d letters)", buffer, len); // 通过长度追加当前接受到的字符串 unsigned char i; for(i = 1; i < 9; i++) writeMatrix(i, disp1[(unsigned char)buffer[0]][i-1]); size_of_message = 1; printk(KERN_INFO "Received characters %c from the user\\n", buffer[0]); return len;
/** @brief 当设备被用户空间程序关闭/释放时调用的函数。 * @param inodep 指向inode对象的指针（定义在linux/fs.h头文件中） * @param filep 指向文件对象的指针（定义在linux/fs.h头文件中） */ static int dev_release(struct inode *inodep, struct file *filep) gpio_free(PIN_DIN); gpio_free(PIN_CS); gpio_free(PIN_CLK); printk(KERN_INFO "Device closed.\\n"); return 0;
/** @brief 内核模块必须使用linux/init.h头文件中提供的module_init()、module_exit()宏， * 在插入和清理的时候标识对应的函数（如上所列） */ module_init(matrix_init); module_exit(matrix_exit); |
编译后，生成后缀为ko的内核模块，使用insmod插入内核模块时，可以看到内核日志中带有初始化的信息提示，在使用open()打开设备文件后，可以看到其打开的信息提示。而通过write()往设备文件中写入数据时，亦可以看到内核日志中接收到字符的提示。
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