汉字点阵与OLED屏线及串口传输

一、两台电脑实现串口通信

(一)实验介绍

本文主要介绍串口传输文件的练习。将两台笔记本电脑，借助 usb转rs232 模块和杜邦线，建立起串口连接。然后用串口助手等工具软件（带文件传输功能）将一台笔记本上的一个大文件（图片、视频和压缩包软件）传输到另外一台电脑，预算文件大小、波特率和传输时间三者之间的关系，并对比实际传输时间。

（二）实验准备

1、材料准备

需要两台电脑，电脑上都下载好串口调试助手，方便接收和发送显示文件。两个串口线连接这两台电脑。打开串口调试助手，开始实验。

2、连线

连线方式：3V3-3V3，GND-GND，TXD-RXD，RXD-TXD

（三）实验过程

打开sscom串口助手，进行下列操作

接收端的串口助手只需要打开串口即可
发送之后点击发送文件
点击保存数据

记下文件下载的地址
将TXT后缀改成.JPG

结论：

理论传输时间 = ( 文件大小 × 8 ) / 波特率
实际时间比理论时间长，说明传输过程中存在丢包重传的过程等，如果调大波特率，传输时间会变快许多

二、点阵汉字的子模读取与显示

(1)实验介绍

学习理解汉字的机内码、区位码编码规则和字形数据存储格式。在Ubuntu下用C/C++(或python) 调用opencv库编程显示一张图片，并打开一个名为"logo.txt"的文本文件（其中只有一行文本文件，包括你自己的名字和学号），按照名字和学号去读取汉字24*24点阵字形字库（压缩包中的文件HZKf2424.hz）中对应字符的字形数据，将名字和学号叠加显示在此图片右下位置。

（2）汉字的机内码、区位码编码规则和字形数据存储格式

请参考：https://blog.youkuaiyun.com/weixin_56102526/article/details/121178128

三、Ubuntu下调用opencv库编程显示图片和学号姓名

(1)实验准备

1、准备下列文件
从压缩包内解压，提取需要的文件粘贴到该文件夹下

2、在logo.txt中写入自己的名字与学号

（2）代码编写

`#include<iostream>
#include<opencv2/imgproc.hpp>
#include"opencv2/opencv.hpp"
#include<opencv/cxcore.h>
#include<opencv/highgui.h>
#include<math.h>

using namespace cv;
using namespace std;

void paint_chinese(Mat& image,int x_offset,int y_offset,unsigned long offset);
void paint_ascii(Mat& image,int x_offset,int y_offset,unsigned long offset);
void put_text_to_image(int x_offset,int y_offset,String image_path,char* logo_path);

int main(){
    String image_path="openCV.jpg";//图片的名字
    char* logo_path="logo.txt";//汉字文件的名字
    put_text_to_image(700,910,image_path,logo_path);//change txt place
    return 0;
}

void paint_ascii(Mat& image,int x_offset,int y_offset,unsigned long offset){
    //绘制的起点坐标
	Point p;
	p.x = x_offset;
	p.y = y_offset;
	 //存放ascii字膜
	char buff[16];           
	//打开ascii字库文件
	FILE *ASCII;

	if ((ASCII = fopen("Asci0816.zf", "rb")) == NULL){
		printf("Can't open ascii.zf,Please check the path!");
		//getch();
		exit(0);
	}

	fseek(ASCII, offset, SEEK_SET);
	fread(buff, 16, 1, ASCII);

	int i, j;
	Point p1 = p;
	for (i = 0; i<16; i++)                  //十六个char
	{
		p.x = x_offset;
		for (j = 0; j < 8; j++)              //一个char八个bit
		{
			p1 = p;
			if (buff[i] & (0x80 >> j))    /*测试当前位是否为1*/
			{
				/*
					由于原本ascii字膜是8*16的，不够大，
					所以原本的一个像素点用4个像素点替换，
					替换后就有16*32个像素点
					ps：感觉这样写代码多余了，但目前暂时只想到了这种方法
				*/
				circle(image, p1, 0, Scalar(0, 0, 255), -1);
				p1.x++;
				circle(image, p1, 0, Scalar(0, 0, 255), -1);
				p1.y++;
				circle(image, p1, 0, Scalar(0, 0, 255), -1);
				p1.x--;
			   circle(image, p1, 0, Scalar(0, 0, 255), -1);
			}						
            p.x+=2;            //原来的一个像素点变为四个像素点，所以x和y都应该+2
		}
		p.y+=2;
	}
}
void paint_chinese(Mat& image,int x_offset,int y_offset,unsigned long offset){//在图片上画汉字
    Point p;
    p.x=x_offset;
    p.y=y_offset;
    FILE *HZK;
    char buff[72];//72个字节，用来存放汉字的

    if((HZK=fopen("HZKf2424.hz","rb"))==NULL){
        printf("Can't open HZKf2424.hz,Please check the path!");
        exit(0);//退出
    }
    fseek(HZK, offset, SEEK_SET);/*将文件指针移动到偏移量的位置*/
    fread(buff, 72, 1, HZK);/*从偏移量的位置读取72个字节，每个汉字占72个字节*/
    bool mat[24][24];//定义一个新的矩阵存放转置后的文字字膜
    int i,j,k;
    for (i = 0; i<24; i++)                 /*24x24点阵汉字，一共有24行*/
	{
        	for (j = 0; j<3; j++)                /*横向有3个字节，循环判断每个字节的*/
			for (k = 0; k<8; k++)              /*每个字节有8位，循环判断每位是否为1*/
				if (buff[i * 3 + j] & (0x80 >> k))    /*测试当前位是否为1*/
				{
					mat[j * 8 + k][i] = true;          /*为1的存入新的字膜中*/
				}
				else {
					mat[j * 8 + k][i] = false;
				}
	}
	
    for (i = 0; i < 24; i++)
	{
		p.x = x_offset;
		for (j = 0; j < 24; j++)
		{		
			if (mat[i][j])
				circle(image, p, 1, Scalar(255, 0, 0), -1);		  //写(替换)像素点
			p.x++;                                                //右移一个像素点
		}
		p.y++;                                                    //下移一个像素点
	}
}

void put_text_to_image(int x_offset,int y_offset,String image_path,char* logo_path){//将汉字弄上图片
//x和y就是第一个字在图片上的起始坐标
    //通过图片路径获取图片
    Mat image=imread(image_path);
    int length=17;//要打印的字符长度（打印多少字节长度就为多少，根据自己的情况调整）
    unsigned char qh,wh;//定义区号，位号
    unsigned long offset;//偏移量
    unsigned char hexcode[30];//用于存放记事本读取的十六进制,记得要用无符号
    FILE* file_logo;

    if ((file_logo = fopen(logo_path, "rb")) == NULL){
		printf("Can't open txtfile,Please check the path!");
		//getch();
		exit(0);
	}

    fseek(file_logo, 0, SEEK_SET);
    fread(hexcode, length, 1, file_logo);
    int x =x_offset,y = y_offset;//x,y:在图片上绘制文字的起始坐标

    for(int m=0;m<length;){
        if(hexcode[m]==0x23){
            break;//读到#号时结束
        }
        else if(hexcode[m]>0xaf){
            qh=hexcode[m]-0xaf;//使用的字库里是以汉字啊开头，而不是以汉字符号开头
            wh=hexcode[m+1] - 0xa0;//计算位码
            offset=(94*(qh-1)+(wh-1))*72L;
            paint_chinese(image,x,y,offset);
            /*
            计算在汉字库中的偏移量
            对于每个汉字，使用24*24的点阵来表示的
            一行有三个字节，一共24行，所以需要72个字节来表示
            */

            m=m+2;//一个汉字的机内码占两个字节，
            x+=24;//一个汉字为24*24个像素点，由于是水平放置，所以是向右移动24个像素点
        }

        else{
        //当读取的字符为ASCII码时
        wh=hexcode[m];
        offset=wh*16l;//计算英文字符的偏移量
        paint_ascii(image,x,y,offset);
        m++;//英文字符在文件里表示只占一个字节，所以往后移一位就行了
        x+=16;
        }

    }

    cv::imshow("image", image);
    cv::waitKey();
}

（3）编译运行

`

注意文本编码格式为ANSI格式，而默认编码格式为utf-8,不然会出现乱码

四、使用STM32与OLED显示内容

（一）显示姓名学号

1、准备资料

2、代码编写

（1）准备字模

（2）修改代码
while循环修改执行的代码

在TEST_MainPage()修改
编译烧录

（二）显示温湿度

温湿度显示read_AHT20函数->bsp_i2c.c文件

void read_AHT20(void)
{
	uint8_t   i;
	for(i=0; i<6; i++)
	{
		readByte[i]=0;
	}

	//-------------
	I2C_Start();

	I2C_WriteByte(0x71);
	ack_status = Receive_ACK();
	readByte[0]= I2C_ReadByte();
	Send_ACK();

	readByte[1]= I2C_ReadByte();
	Send_ACK();

	readByte[2]= I2C_ReadByte();
	Send_ACK();

	readByte[3]= I2C_ReadByte();
	Send_ACK();

	readByte[4]= I2C_ReadByte();
	Send_ACK();

	readByte[5]= I2C_ReadByte();
	SendNot_Ack();
	//Send_ACK();

	I2C_Stop();

	//--------------
	if( (readByte[0] & 0x68) == 0x08 )
	{
		H1 = readByte[1];
		H1 = (H1<<8) | readByte[2];
		H1 = (H1<<8) | readByte[3];
		H1 = H1>>4;

		H1 = (H1*1000)/1024/1024;

		T1 = readByte[3];
		T1 = T1 & 0x0000000F;
		T1 = (T1<<8) | readByte[4];
		T1 = (T1<<8) | readByte[5];

		T1 = (T1*2000)/1024/1024 - 500;

		AHT20_OutData[0] = (H1>>8) & 0x000000FF;
		AHT20_OutData[1] = H1 & 0x000000FF;

		AHT20_OutData[2] = (T1>>8) & 0x000000FF;
		AHT20_OutData[3] = T1 & 0x000000FF;
	}
	else
	{
		AHT20_OutData[0] = 0xFF;
		AHT20_OutData[1] = 0xFF;

		AHT20_OutData[2] = 0xFF;
		AHT20_OutData[3] = 0xFF;
		printf("lyy");

	}
	/*通过串口显示采集得到的温湿度
	printf("\r\n");
	printf("温度:%d%d.%d",T1/100,(T1/10)%10,T1%10);
	printf("湿度:%d%d.%d",H1/100,(H1/10)%10,H1%10);
	printf("\r\n");*/
	t=T1/10;
	t1=T1%10;
	a=(float)(t+t1*0.1);
	h=H1/10;
	h1=H1%10;
	b=(float)(h+h1*0.1);
	sprintf(strTemp,"%.1f",a);   //调用Sprintf函数把DHT11的温度数据格式化到字符串数组变量strTemp中  
    sprintf(strHumi,"%.1f",b);    //调用Sprintf函数把DHT11的湿度数据格式化到字符串数组变量strHumi中  
	GUI_ShowCHinese(16,00,16,"温湿度显示",1);
	GUI_ShowCHinese(16,20,16,"温度",1);
	GUI_ShowString(53,20,strTemp,16,1);
	GUI_ShowCHinese(16,38,16,"湿度",1);
	GUI_ShowString(53,38,strHumi,16,1);
	delay_ms(1500);		
	delay_ms(1500);
}

文字显示

	"温",0x00,0x00,0x23,0xF8,0x12,0x08,0x12,0x08,0x83,0xF8,0x42,0x08,0x42,0x08,0x13,0xF8,
  0x10,0x00,0x27,0xFC,0xE4,0xA4,0x24,0xA4,0x24,0xA4,0x24,0xA4,0x2F,0xFE,0x00,0x00,/*"温",0*/
	"度",0x01,0x00,0x00,0x80,0x3F,0xFE,0x22,0x20,0x22,0x20,0x3F,0xFC,0x22,0x20,0x22,0x20,
  0x23,0xE0,0x20,0x00,0x2F,0xF0,0x24,0x10,0x42,0x20,0x41,0xC0,0x86,0x30,0x38,0x0E,/*"度",0*/
	"湿",0x00,0x00,0x27,0xF8,0x14,0x08,0x14,0x08,0x87,0xF8,0x44,0x08,0x44,0x08,0x17,0xF8,
  0x11,0x20,0x21,0x20,0xE9,0x24,0x25,0x28,0x23,0x30,0x21,0x20,0x2F,0xFE,0x00,0x00,/*"湿",0*/
	"显",0x00,0x00,0x1F,0xF0,0x10,0x10,0x10,0x10,0x1F,0xF0,0x10,0x10,0x10,0x10,0x1F,0xF0,
  0x04,0x40,0x44,0x44,0x24,0x44,0x14,0x48,0x14,0x50,0x04,0x40,0xFF,0xFE,0x00,0x00,/*"显",0*/
	"示",0x00,0x00,0x3F,0xF8,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xFF,0xFE,0x01,0x00,
  0x01,0x00,0x11,0x10,0x11,0x08,0x21,0x04,0x41,0x02,0x81,0x02,0x05,0x00,0x02,0x00,/*"示",0*/

主函数main.c文件

#include "delay.h"
#include "usart.h"
#include "bsp_i2c.h"
#include "sys.h"

#include "oled.h"
#include "gui.h"
#include "test.h"

int main(void)
{	
	delay_init();	    	       //延时函数初始化    	  
	uart_init(115200);	 
	IIC_Init();
		  
	NVIC_Configuration(); 	   //设置NVIC中断分组2:2位抢占优先级，2位响应优先级 	
	OLED_Init();			         //初始化OLED  
	OLED_Clear(0); 
	while(1)
	{
		//printf("温度湿度显示");
		read_AHT20_once();
		OLED_Clear(0); 
		delay_ms(1500);
  }
}

烧录效果

（三)上下或左右的滑动显示长字符

在显示姓名学号的代码里修改

代码修改

/*--  文字:  醉  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"醉",0x00,0x40,0xFE,0x20,0x29,0xFE,0x28,0x00,0xFE,0x88,0xAA,0x88,0xAB,0x54,0xAA,0x22,
0xAE,0x00,0xC2,0x20,0x83,0xFE,0xFE,0x20,0x82,0x20,0x82,0x20,0xFE,0x20,0x82,0x20

/*--  文字:  后  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"后",0x00,0x10,0x00,0xF8,0x1F,0x00,0x10,0x00,0x10,0x00,0x1F,0xFE,0x10,0x00,0x10,0x00,
0x10,0x00,0x17,0xF8,0x14,0x08,0x24,0x08,0x24,0x08,0x44,0x08,0x87,0xF8,0x04,0x08

/*--  文字:  不  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"不",0x00,0x00,0x7F,0xFC,0x00,0x80,0x00,0x80,0x01,0x00,0x01,0x00,0x03,0x40,0x05,0x20,
0x09,0x10,0x11,0x08,0x21,0x04,0x41,0x04,0x81,0x00,0x01,0x00,0x01,0x00,0x01,0x00

/*--  文字:  知  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"知",0x20,0x00,0x20,0x00,0x20,0x7C,0x7E,0x44,0x48,0x44,0x88,0x44,0x08,0x44,0x08,0x44,
0xFF,0x44,0x08,0x44,0x14,0x44,0x14,0x44,0x22,0x7C,0x22,0x44,0x42,0x00,0x80,0x00

/*--  文字:  天  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"天",0x00,0x00,0x3F,0xF8,0x01,0x00,0x01,0x00,0x01,0x00,0x01,0x00,0xFF,0xFE,0x01,0x00,
0x02,0x80,0x02,0x80,0x04,0x40,0x04,0x40,0x08,0x20,0x10,0x10,0x20,0x08,0xC0,0x06

/*--  文字:  在  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"在",0x02,0x00,0x02,0x00,0x04,0x00,0xFF,0xFE,0x08,0x00,0x08,0x40,0x10,0x40,0x30,0x40,
0x57,0xFC,0x90,0x40,0x10,0x40,0x10,0x40,0x10,0x40,0x10,0x40,0x1F,0xFE,0x10,0x00

/*--  文字:  水  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"水",0x01,0x00,0x01,0x00,0x01,0x00,0x01,0x08,0x01,0x08,0x7D,0x90,0x05,0xA0,0x09,0x40,
0x09,0x40,0x11,0x20,0x11,0x10,0x21,0x08,0x41,0x06,0x81,0x00,0x05,0x00,0x02,0x00

/*--  文字:  满  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"满",0x01,0x08,0x21,0x08,0x17,0xFE,0x11,0x08,0x80,0x00,0x47,0xFE,0x40,0x90,0x10,0x90,
0x17,0xFE,0x24,0x92,0xE4,0x92,0x25,0x6A,0x26,0x46,0x24,0x02,0x24,0x0A,0x04,0x04

/*--  文字:  床  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"床",0x01,0x00,0x00,0x80,0x3F,0xFE,0x20,0x00,0x20,0x80,0x20,0x80,0x2F,0xFC,0x20,0x80,
0x21,0xC0,0x22,0xA0,0x22,0xA0,0x24,0x90,0x48,0x88,0x50,0x86,0x80,0x80,0x00,0x80

/*--  文字:  清  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"清",0x00,0x40,0x20,0x40,0x17,0xFC,0x10,0x40,0x83,0xF8,0x40,0x40,0x47,0xFE,0x10,0x00,
0x13,0xF8,0x22,0x08,0xE3,0xF8,0x22,0x08,0x23,0xF8,0x22,0x08,0x22,0x28,0x02,0x10

/*--  文字:  梦  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"梦",0x08,0x20,0x08,0x20,0x7E,0xFC,0x08,0x20,0x1C,0x70,0x2A,0xA8,0xC8,0x26,0x04,0x00,
0x07,0xF0,0x08,0x10,0x14,0x20,0x22,0x40,0x01,0x80,0x02,0x00,0x0C,0x00,0x70,0x00

/*--  文字:  压  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"压",0x00,0x00,0x3F,0xFE,0x20,0x00,0x20,0x80,0x20,0x80,0x20,0x80,0x20,0x80,0x2F,0xFC,
0x20,0x80,0x20,0x80,0x20,0x90,0x20,0x88,0x20,0x88,0x40,0x80,0x5F,0xFE,0x80,0x00

/*--  文字:  星  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"星",0x00,0x00,0x1F,0xF0,0x10,0x10,0x1F,0xF0,0x10,0x10,0x1F,0xF0,0x01,0x00,0x11,0x00,
0x1F,0xF8,0x21,0x00,0x41,0x00,0x1F,0xF0,0x01,0x00,0x01,0x00,0x7F,0xFC,0x00,0x00

/*--  文字:  河  --*/
/*--  宋体12;  此字体下对应的点阵为：宽x高=16x16   --*/
"河",0x00,0x00,0x20,0x00,0x17,0xFE,0x10,0x08,0x80,0x08,0x43,0xC8,0x42,0x48,0x12,0x48,
0x12,0x48,0x22,0x48,0xE3,0xC8,0x22,0x48,0x20,0x08,0x20,0x08,0x20,0x28,0x00,0x10

test.c文件的修改

结果展示

总结：

在进行OLED的显示时，首先需要对字模进行取模，注意不要把字模取反，不然就无法得到正确的字样。本次的实践较为简单是基于厂家所给的程序搭建一个大框架的基础上进行修改的结果，比较容易实现，注意在接入温度传感器时，不要将引脚接错，避免造成严重的后果。

参考：

【1】https://blog.youkuaiyun.com/qq_26387811/article/details/121318215
【2】https://blog.youkuaiyun.com/weixin_56102526/article/details/121178128
【3】https://blog.youkuaiyun.com/wakeup_high/article/details/134387755
【4】https://blog.youkuaiyun.com/qq_46467126/article/details/121439142