1.IIC协议介绍
IIC全称Inter-Integrated Circuit (集成电路总线) 简称I2C
是由PHILIPS公司在80年代开发的两线式串行总线,用于连接微控制器及其外围设备。IIC属于半双工同步通信方式
特点
简单性和有效性
由于接口直接在组件之上,因此IIC总线占用的空间非常小,减少了电路板的空间和芯片管脚的数量,降低了互联成本。总线的长度可高达25英尺,并且能够以10Kbps的最大传输速率支持40个组件
多主控(multimastering)
其中任何能够进行发送和接收的设备都可以成为主总线。一个主控能够控制信号的传输和时钟频率。当然,在任何时间点上只能有一个主控。
构成
IIC串行总线一般有两根信号线,一根是双向的数据线SDA,另一根是时钟线SCL,其时钟信号是由主控器件产生。所有接到IIC总线设备上的串行数据SDA都接到总线的SDA上,各设备的时钟线SCL接到总线的SCL上。对于并联在一条总线上的每个IC都有唯一的地址。
2.项目效果
在OLED屏幕上显示字符或者图像
3.IIC协议
就是根据IIC的时序对相应的寄存器写入数据,进行操作。
IIC总线在传输数据的过程中一共有三种类型信号,分别为:开始信号、结束信号和应答信号。
起始位,停止位,数据位,速度
这些信号中,起始信号是必需的,结束信号和应答信号
应答信号
发送器每发送一个字节(8个bit),在时钟脉冲9期间释放数据线,由接收器反馈一个应答信号。
应答信号为低电平时,规定为有效应答位(ACK,简称应答位),表示接收器已经成功地接收了该字节;
应答信号为高电平时,规定为非应答位(NACK),一般表示接收器接收该字节没有成功。
数据发送的时序
4.OLED写命令
4.1 OLED的寻址模式
寻址模式的寄存器
页地址模式
水平地址模式
行地址(page x)选择
列地址选择 (分低位设置和高位设置)
主函数最后 用while(1) 卡主,不然会一直设置OLED的屏幕,一直刷新。
5.代码实现- 图
需要配合 字膜提取软件+画图工具(自带) 转换为分辨率位128x64的bmp图像。
#include "reg52.h"
#include "intrins.h"sbit sda=P0^3;
sbit scl=P0^1;void i2c_start(void);
void i2c_stop(void);
char ack(void);
void send_messege_i2c(char messege);
void w_cmd_i2c(char cmd);
void w_data_i2c(char data1);
void init_i2c(void);
void clear_oled(void);code char tx[]={
0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,
0x01,0x03,0x03,0x03,0x07,0x07,0x05,0x07,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x01,
0x05,0x0F,0x0F,0x0F,0x07,0x05,0x07,0x05,0x07,0x07,0x07,0x0F,0x0F,0x0F,0x0F,0x0F,
0x0F,0x4F,0x0F,0x0F,0x0F,0x0F,0x0F,0x1F,0x1F,0x1F,0x0F,0x0F,0x1F,0x1F,0x1F,0x1F,
0x1F,0x3F,0x1F,0x1F,0x7F,0x1F,0x1F,0x9F,0x9F,0x3F,0x7F,0x6F,0x6F,0x5F,0x9F,0xBF,
0xBF,0xBF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x08,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x01,0x01,0x03,0x1F,0x1F,0x1F,0x3F,0x3F,0x1F,
0xCF,0xEF,0xF7,0xD7,0xDF,0xFB,0xFF,0x9F,0x9E,0x9F,0x8F,0x8F,0x9F,0x9F,0x9F,0xBF,
0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x40,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0xF0,0xF0,0xF0,0xF0,0xF8,0xF8,0xF8,0xF8,0xFC,0xFC,
0xFC,0xFC,0xFC,0xFC,0xFC,0xFC,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFC,0xE0,0xC0,0x80,
0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x02,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x01,0x0C,0x44,0x60,0xF5,0xE0,0xC0,0xC0,0xC0,0xC0,0xC0,0xD8,0xFE,0xE7,0xE5,
0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x40,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0xC0,0xC0,0x80,0x80,0x00,0x08,0x08,
0xC8,0x98,0x98,0x88,0x80,0x80,0xC0,0x81,0x81,0xC7,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xDF,0x87,0x87,0xC3,0xC3,0xA3,0x91,0x91,0x11,0x11,0x19,0x99,0x89,0x09,0x09,
0x01,0x83,0xC3,0xC2,0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x03,0x37,0x3D,0xBF,0xBF,0x3F,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0x00,0x00,0x20,0x40,0x40,0x40,0x40,0x06,0x06,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x02,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x1E,0x3E,0x7C,0x70,0xE0,0xC3,0x1F,0x3F,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x7F,0x7F,0x7F,0x7F,0xFF,0xFF,0xFF,
0x7F,0x7F,0x7F,0x7F,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0x1F,0x00,0x00,0x40,0x70,0x3C,0x1C,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0xC0,0xA0,0xC0,0xC0,0x00,0xC5,0xFF,0xFF,0xFF,0xFF,0xFD,0xFD,0xFF,0xFF,0xFF,
0xFF,0xFF,0x00,0x00,0x00,0x80,0x00,0x80,0x00,0x00,0xC0,0xC0,0x00,0xC0,0xC0,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x08,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x0F,0x3F,0x7F,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xDF,0x9F,0x9F,0x1F,0x1F,0x1E,0x9E,0xDE,0xDE,0xDE,0xDE,0xDE,
0xDE,0x1E,0x1C,0x1C,0x1F,0x1F,0x9F,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x7F,0x3F,0x1F,
0x1F,0x07,0x03,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0x00,0x00,0x00,
0x40,0x40,0x00,0x00,0x00,0x00,0x30,0x08,0x08,0x03,0x80,0x80,0x80,0xF8,0xF8,0xFE,
0xEF,0xC7,0xE7,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFD,0xFD,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0x00,0x00,0xE0,0xEF,0xE0,0xEF,0xE0,0x80,0x0F,0x6F,0x60,0xCF,0xAF,0xBF,
0x23,0x84,0xC0,0xA0,0xE0,0xE0,0xE0,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x02,
0x02,0x04,0x00,0x00,0x00,0x00,0x20,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x01,0x07,0x0F,0x1F,0x3F,0x3F,0x7F,0x7C,0x7C,0xF8,0xF9,0xFB,0xFB,0xFB,0xFB,0xF9,
0xF9,0x78,0x78,0x7C,0x3E,0x3F,0x1F,0x1F,0x0F,0x07,0x03,0x01,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xC1,0xE1,0xFF,0xFF,0xFE,0xFE,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0x00,0x00,0x9F,0xBF,0xDF,0xFF,0xFF,0xEF,0xE0,0x98,0x98,0x9A,0x87,0xA7,
0xA7,0x8F,0x8F,0x9F,0x9F,0x9A,0x9E,0x9C,0xFF,0xFB,0xFA,0xFC,0xFC,0xFC,0xEC,0xE8,
0xF8,0xF0,0xB0,0xB0,0xA0,0xE0,0xC0,0xC0,0xC0,0x80,0x80,0x80,0x80,0x00,0x00,0x20,
0x00,0x00,0x00,0x40,0xC0,0xC0,0x44,0x04,0x00,0x00,0x00,0x00,0x80,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0xC0,0xC0,0xC0,0xC0,0xC0,0xC0,0xC0,0xE0,0xE0,0xE0,0xE0,0xE0,
0xE0,0xD0,0xB0,0xF0,0xF8,0xF8,0xB8,0x9C,0xDC,0xDC,0x7E,0xFC,0xE4,0xEC,0xEC,0xF4,
0xF8,0xF8,0xFC,0xFC,0xF4,0xFE,0xFE,0xFE,0xFE,0xFF,0xFD,0xFF,0xFF,0xFF,0xFF,0xFF,
0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF}; //这是page7的内容void main(void)
{ unsigned char i;unsigned int j;/*-- 文字: 我 --*/
/*-- 宋体12; 此字体下对应的点阵为:宽x高=16x16 --*/init_i2c();clear_oled(); //清屏函数w_cmd_i2c(0x20); //选择页寻址模式w_cmd_i2c(0x02);//w_cmd_i2c(0xB0); //选择page 1011 0xxx//w_cmd_i2c(0x00); //设置起始地址 低位//w_cmd_i2c(0x10); //设置起始地址 高位//w_data_i2c(0x80); //发送数据for(i=0;i<8;i++){w_cmd_i2c(0xB0+i); //变换page 共有0-7 8个w_cmd_i2c(0x00); //设置起始地址 低位w_cmd_i2c(0x10); //设置起始地址 高位//i=3;for(j=128*i; j<(128*(i+1)); j++){ //变换的是tx中的数据w_data_i2c(tx[j]); //tx中的数据 }}while(1){}
}
//下面是函数封装void clear_oled(void)
{char i; int j;for(i=0;i<8;i++){w_cmd_i2c(0xB0+i); //变换pagew_cmd_i2c(0x00); //设置起始地址 低位w_cmd_i2c(0x10); //设置起始地址 高位for(j=0;j<128;j++){w_data_i2c(0x00); //写0就行 }}}void init_i2c(void)
{w_cmd_i2c(0xAE);//--display offw_cmd_i2c(0x00);//---set low column addressw_cmd_i2c(0x10);//---set high column addressw_cmd_i2c(0x40);//--set start line address w_cmd_i2c(0xB0);//--set page addressw_cmd_i2c(0x81); // contract controlw_cmd_i2c(0xFF);//--128 w_cmd_i2c(0xA1);//set segment remapw_cmd_i2c(0xA6);//--normal / reversew_cmd_i2c(0xA8);//--set multiplex ratio(1 to 64)w_cmd_i2c(0x3F);//--1/32 dutyw_cmd_i2c(0xC8);//Com scan directionw_cmd_i2c(0xD3);//-set display offsetw_cmd_i2c(0x00);//w_cmd_i2c(0xD5);//set osc divisionw_cmd_i2c(0x80);//w_cmd_i2c(0xD8);//set area color mode offw_cmd_i2c(0x05);//w_cmd_i2c(0xD9);//Set Pre-Charge Periodw_cmd_i2c(0xF1);//w_cmd_i2c(0xDA);//set com pin configuartionw_cmd_i2c(0x12);//w_cmd_i2c(0xDB);//set Vcomhw_cmd_i2c(0x30);//w_cmd_i2c(0x8D);//set charge pump enablew_cmd_i2c(0x14);//w_cmd_i2c(0xAF);//--turn on oled panel
}void w_cmd_i2c(char cmd)
{i2c_start();send_messege_i2c(0x78);ack();send_messege_i2c(0x00);ack();send_messege_i2c(cmd);ack();i2c_stop();
}void w_data_i2c(char data1)
{i2c_start();send_messege_i2c(0x78);ack();send_messege_i2c(0x40);ack();send_messege_i2c(data1);ack();i2c_stop();
}void i2c_start(void)
{scl=1;sda=0; sda=1; //我的 /*scl=0; //老师的sda=1;scl=1;*/_nop_(); //sda=0;_nop_(); //scl=0;
}void i2c_stop(void)
{scl=0;sda=0;scl=1;_nop_(); //sda=1;_nop_(); //sda=0; //老师不要这个
}char ack(void) //应答信号
{char flag;sda=1;//_nop_(); //老师要的scl=1;_nop_();flag=sda;//_nop_(); //老师要的scl=0;_nop_();return flag;
}void send_messege_i2c(char messege)
{char i;for(i=0;i<8;i++){scl=0;_nop_(); //必要sda= messege & 0x80 ; //_nop_(); //老师要的scl=1;_nop_();scl=0;messege=messege<<1;}
}
6.编译的注意事项
其中的data 、xdata为ram的中的数据,可以随程序执行变化。
code中为rom中数据,调用后更改不了。5中的图片点阵太大,也不需要更改,编码在code中即可