12864显示图形中上半屏和下半屏
12864液晶的说明

液晶12864(KS0108主控)12864市面上比较流行的有两种,一种是以KS0108为主控芯片的,不带字库的,说白了就是只能靠打点才能显示出字符或图形的,当然要借助取模软件;另一种是以ST7920为主控芯片的,带ASCII码和中文字库。
至于两种的区别下一篇再讨论,这篇先讲述KS0108为主控芯片的12864的原理。
这是网上找的一个管脚图,当然不同品牌的可能略有差异,但是主要的还是一样的重点要讲一下CS1和CS2,KS0108控制的12864内部有两个控制器,分别控制左半屏和右半屏,如下图所示左半屏和右半屏操作时写的地址其实是一样的,那么只能通过片选CS1和CS2来选择哪半个屏了,如果两个都选通,则相当于两块64x64的液晶了,而且显示的内容是一样的,取模方式是纵向8点下高位。
好了,来说下原理,列的范围是0~63,我已经标出了,行是不能按位来写的,而是写“页”,一个页相当于8个点,也就是8位,即一个字符,高位在下面,那么页的范围是0~7,共8页,8页x8个点正好64个点。
这是我用取模软件截的一个“们”字,可以看出它是16x16大小的,实际上占用了两个“页”,16个列,而我们操作时先固定一个页,比如这个就先写上面那页,假设为n好了,从列0写到16,然后页n+1,再从列0写到16,这样一个“们”字就出来了,下面是其代码0x40,0x20,0xF8,0x07,0x00,0xF8,0x02,0x04, 0x08,0x04,0x04,0x04,0x04,0xF E,0x04,0x00,0x00,0x00,0xFF,0x00,0x00,0xFF,0x00,0x00,0x00,0x00,0x00,0x40,0x80,0x7F ,0x00,0x00,可见16x16的字符占了32个字节(上面n页16个字节加n+1页16个),那么如果一幅满幅的图片,就是128x64,占用128x8=1K个字节,可见还是非常占空间的。
液晶显示12864

液晶显示12864事无巨细,LCD12864上次写了1602的使用,这次来写写LCD12864。
作为绝大多数单片机学习板的液晶显示模块之一,LCD12864功能要比LCD1602要强悍许多。
仅仅是1602的两行英文字母,数字和各种符号,严格来说勉强能显示几个中文,是无法满足我们的需求的。
当需要显示一些稍微复杂的图形的时候,12864的用处就显现出来了。
下面是两个正在工作的LCD12864:跟1602一样,各种型号的LCD12864在价格,性能,效率上也都是大同小异。
据我所知,市场上全新的12864价格在50到80不等,感觉有点贵。
不过,如果你要买的话,最好了解清楚它是不是带字库的。
什么是字库呢?就是在12864里的CGROM存储器里存放有可调用显示的绝大部分的中文和各种符号。
这和我们调用GCC-AVR的各种头文件里的子函数有点类似:如果没有这个头文件,那么你只能自己去编写;同样如果12864没有字库,你也需要自己去编一个字库,只是方式上是通过图形取模软件来转换实现的。
建议对自己实力不太自信的朋友购买带字库的LCD12864。
LCD12864,即像素为128*64的显示液晶。
它的每一行横向一共有128个可显示点,每一列纵向有64个,这些“点”其实也都是一个个发光二极管。
它可以在一个16*16的点阵区域上显示一个中文;也可以在一个8*16的点阵区域显示一个非中文字符,一般称为半宽字体。
即一个中文字所占显示面积是一个非中文字符的两倍。
LCD12864其实还有个叫法叫12864图形点阵,看出关键了么?对了,点阵二字。
归根结底,它是一个点阵。
既然是点阵,那么它的工作原理就和我们以前接触的LED点阵类似。
即在要点亮的“点”上赋予正向压降即可。
理解这点,对使用12864的图形显示功能有基础作用。
关于LCD12864的引脚结构和功能,并非全部的LCD12864引脚都是一样的。
在此无法一一叙述。
我们论坛板子的LCD12864接口是20个引脚,并行数据总线的LCD12864。
12864液晶画点和画任意两点间直线 原理

12864液晶画点和画任意两点间直线原理、算法及程序原码12864液晶画点和画任意直线的原理和算法程序原码经验证可行12864实际上是256x64二维显示空间,整个液晶屏分上下两个半屏。
整个屏一共有256列,64行。
可以把它分成16大列,每一大列包含16列。
图形RAM的起始址址为0x80,设置读或写的地址时,要先写Y坐标,再写X坐标。
要使用画图功能,就要设置扩允指令集。
画点原理:先确定坐标->读出数据->修改数据->数据写回原处。
程序原码://画点函数void Draw_Point(uchar x,uchar y,uchar color){uchar row,tier,row_bit;uchar ReadOldH,ReadOldL;tier=x>>4; //把256列分成16大列,每大列包含16列row_bit=x&0x0f; //计算所给坐标在某一大列中的哪一列if(y<32) //分上下半屏显示row=y; //上半屏else{row=y-32; //下半屏tier+=8;}WriteCommand(0x34); //8Bit扩充指令集,即使是36H也要写两次WriteCommand(0x36); //绘图ON,基本指令集里面36H不能开绘图WriteCommand(0x80+row); // 行位置WriteCommand(0x80+tier); // 列位置ReadData();ReadOldH=ReadData();//某大列的前8列数据,低位在前,高位在后ReadOldL=ReadData();//某大列的后8列数据if( row_bit < 8 ) //修改读出的数据{switch( color){case 0 : ReadOldH &=( ~( 0x01 << ( 7 - row_bit ))) ;break ;case 1 : ReadOldH |= ( 0x01 << ( 7 - row_bit )) ;break ;case 2 : ReadOldH ^= ( 0x01 << ( 7 - row_bit )) ;break ;default : break ;}}else{switch(color){case 0 : ReadOldL &= (~( 0x01 << ( 15 - row_bit ))) ;break ;case 1 : ReadOldL |= ( 0x01 << ( 15 - row_bit )) ;break ;case 2 : ReadOldL ^= ( 0x01 << ( 15 - row_bit )) ;break ;default : break ;}}WriteCommand(0x80+row); // 行位置WriteCommand(0x80+tier); // 列位置WriteData( ReadOldH ) ;//把修改后的数据写回原地址WriteData( ReadOldL ) ;}画任意两点间直线的原理和算法:采用Bresenham画线算法。
液晶12864显示图片

液晶12864显示图片液晶12864简介12864是128*64点阵液晶模块的点阵数简称。
基本参数1、低电源电压(VDD:+3.0~+5.5V)。
2、显示分辨率:128×64 点。
3、内置汉字字库,提供8192 个16×16 点阵汉字。
4、内置128 个16×8 点阵字符。
5、2MHZ 时钟频率。
6、显示方式:STN、半透、正显。
7、驱动方式:1/32DUTY,1/5BIAS。
8、视角方向:6 点。
9、背光方式:侧部高亮白色LED。
10、通讯方式:串行、并口可选。
11、内置DC-DC 转换电路,无需外加负压。
12、无需片选信号,简化软件设计。
13、工作温度: 0℃~+55℃ ,存储温度: -20℃~+60℃。
液晶12864接口液晶12864显示图片程序源代码/*******************12864显示图片******************** 处理器:51单片机* 开发环境:keil* 功能:12864显示图片****************************************************/#include <reg51.h>#include <intrins.h>#define uchar unsigned char#define uint unsigned int/*12864端口定义 */#define LCD_data P0 //数据口sbit LCD_RS = P1^0; //寄存器选择输入sbit LCD_RW = P1^1; //液晶读/写控制sbit LCD_EN = P2^5; //液晶使能控制sbit LCD_PSB = P1^2; //串/并方式控制unsigned char code zhu[]={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, 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, 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, 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, 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, 0xFF,0xFF,0xFF,0xFE,0x7D,0x7F,0xFF,0xFF,0xFF,0xFD,0xEF,0xFF,0xF0,0x04,0x3F,0xFF, 0xFF,0xFF,0xFF,0xFD,0xBD,0x7F,0xFF,0xFF,0xFF,0xE6,0xE7,0xFF,0xF4,0x00,0x7F,0xFF, 0xFF,0xFF,0xFF,0xFD,0x3D,0x7F,0xFF,0xFF,0xFF,0xDE,0x00,0xFF,0xF0,0x00,0x7F,0xFF, 0xFF,0xFF,0xFF,0xC4,0x3E,0x7F,0xFF,0xFF,0xFF,0xA8,0x00,0x1F,0xF0,0x00,0x7F,0xFF, 0xFF,0xFF,0xFF,0xBA,0x46,0x7F,0x7F,0xFF,0xFF,0x70,0x00,0x0E,0xF0,0x00,0xFF,0xFF, 0xFF,0xFF,0xFF,0x7D,0xBB,0x5F,0x7F,0xFF,0xFE,0xE1,0x70,0x01,0xF0,0x00,0xFF,0xFF, 0xFF,0xFF,0xFF,0x7D,0xA3,0xEF,0x9F,0xFF,0xFF,0x06,0xF8,0x03,0xF0,0x00,0xFF,0xFF, 0xFF,0xFF,0xF0,0x7C,0x07,0xB6,0x07,0xFF,0xFF,0xCC,0xF9,0x81,0xF0,0x01,0xFF,0xFF, 0xFF,0xFF,0xEF,0x75,0xDF,0xB8,0x01,0xFF,0xFF,0x98,0xF9,0x80,0xF1,0xF1,0xEF,0xFF, 0xFF,0xFF,0xEF,0x6D,0xEF,0x58,0xE0,0xFF,0xFF,0x90,0x70,0x00,0xF3,0xFB,0xFF,0xFF, 0xFF,0xFF,0xEF,0xBB,0xEE,0xD9,0xF0,0xFF,0xFF,0xB0,0x0C,0x00,0x73,0x1B,0xAF,0xFF, 0xFF,0xFF,0xF7,0x87,0xAE,0xC2,0xF0,0x7F,0xFF,0xE0,0x0C,0x62,0x36,0xFD,0xFF,0xFF, 0xFF,0xFF,0xF0,0x33,0xDD,0xD2,0x60,0x7F,0xFF,0xE0,0x31,0x61,0x76,0xFD,0xEF,0xFF, 0xFF,0xFF,0xEF,0xA0,0x3B,0xF4,0x18,0x3F,0xFF,0xE0,0x30,0x09,0x6C,0x3D,0xFF,0xFF, 0xFF,0xFF,0xDF,0x83,0xB6,0xA5,0x98,0x3F,0xFF,0xE0,0x00,0x01,0x7B,0xDD,0xAF,0xFF, 0xFF,0xFF,0xDE,0x83,0xCF,0xED,0x80,0x3F,0xFF,0xE0,0x00,0x01,0xFA,0xDD,0xFF,0xFF, 0xFF,0xFF,0xDD,0x7B,0xDE,0xF4,0x00,0x3F,0xFF,0xE0,0x00,0x09,0xFB,0xDD,0xEF,0xFF, 0xFF,0xFF,0xEE,0x5B,0xDF,0xF4,0x00,0x3F,0xFF,0xF0,0x00,0x29,0xF9,0xBB,0xFF,0xFF, 0xFF,0xFF,0xF1,0x79,0xBE,0xB4,0x00,0x3F,0xFF,0xF0,0x00,0x33,0xFF,0xFA,0xAF,0xFF, 0xFF,0xFF,0xEF,0x68,0x03,0xF8,0x00,0x3F,0xFF,0xF8,0x0F,0xE3,0xFF,0xF7,0xFF,0xFF, 0xFF,0xFF,0xDF,0x70,0x16,0xEA,0x01,0x3F,0xFF,0xF8,0x1F,0xC7,0xEF,0xF6,0xEF,0xFF, 0xFF,0xFF,0x07,0x80,0x0F,0xFA,0x1D,0x7F,0xE0,0x3C,0x7F,0x87,0xEF,0xEF,0xFF,0xFF, 0xFF,0xFF,0x0B,0xA0,0x2A,0xB6,0x1E,0x70,0x1F,0xBF,0x3E,0x0F,0xD3,0x9A,0xAF,0xFF, 0xFF,0xFF,0x85,0xA0,0x5F,0xF7,0x3C,0xF7,0xE0,0x3C,0x00,0x3F,0xDC,0x7F,0xFF,0xFF, 0xFF,0xFF,0x41,0x11,0x2E,0xF6,0x81,0xF8,0x00,0x3F,0x00,0xFF,0xAF,0x8E,0xEF,0xFF, 0xFF,0xFF,0x94,0xA0,0xFF,0xF7,0xFF,0xF8,0x00,0x3F,0xFF,0x1F,0xBF,0x77,0xFF,0xFF, 0xFF,0xFF,0xE2,0x3F,0xAA,0xB7,0x8B,0xFC,0x00,0x3F,0xDF,0xDF,0x6A,0xFA,0xAF,0xFF, 0xFF,0xFF,0x88,0x01,0xFF,0xFB,0x75,0xFC,0x00,0x3F,0xDF,0xBE,0xFE,0xFB,0xFF,0xFF, 0xFF,0xFF,0x40,0x00,0x3E,0xEB,0xB7,0xFE,0x00,0x3F,0xE0,0x7C,0x78,0xFB,0xF7,0xFF, 0xFF,0xFF,0x00,0x00,0x0F,0xFD,0xC7,0xFE,0x01,0xBF,0xFF,0xFA,0xA7,0x70,0x6F,0xFF, 0xFF,0xFF,0x0F,0xBF,0x0A,0xAA,0xFF,0xFE,0x0F,0xBF,0xFF,0xE7,0xCF,0x8F,0xAF,0xFF, 0xFF,0xFF,0x47,0x5E,0x2F,0xFF,0x7F,0xFF,0x1F,0xBF,0xFF,0xDF,0xEF,0x8F,0xAF,0xFF, 0xFF,0xFF,0x38,0x21,0xDE,0xEE,0x9F,0xFF,0xBF,0x7F,0xFF,0x3F,0xEF,0x0F,0xB7,0xFF, 0xFF,0xFF,0x07,0xD6,0x2F,0xFF,0xE7,0xFF,0xC0,0xFF,0xFC,0xFF,0xF0,0xEF,0xBF,0xFF, 0xFF,0xFF,0x41,0x8C,0xCA,0xBA,0xB9,0xFF,0xFF,0xFF,0xE3,0xFF,0xFD,0xF0,0x6F,0xFF, 0xFF,0xFF,0x93,0xCC,0xDF,0xFF,0xFE,0x3F,0xFF,0xFE,0x00,0x7F,0xFD,0xF7,0x7F,0xFF, 0xFF,0xFF,0x40,0x03,0x2E,0xEE,0xEF,0xC2,0x03,0xC0,0xFF,0x9F,0xFD,0xF7,0xAF,0xFF, 0xFF,0xFF,0xC0,0x03,0x3F,0xFF,0xFF,0xF9,0xFC,0x37,0xFF,0xE3,0xFE,0xE7,0xDF,0xFF, 0xFF,0xFF,0xD1,0xCC,0xFB,0xBB,0xBB,0xE7,0xFF,0x8F,0xFF,0xFC,0x3E,0x17,0xDF,0xFF,0xFF,0xFF,0xC0,0x8C,0xFF,0xFF,0xFF,0x9F,0xFF,0xDF,0xFF,0xFF,0xC6,0xF7,0xEF,0xFF,0xFF,0xFF,0xC0,0x90,0x2F,0xEF,0xEE,0x7F,0xFF,0xBF,0xFF,0xFF,0xF9,0xFB,0xF7,0xFF,0xFF,0xFF,0xC0,0xA0,0x3F,0xFF,0xF9,0xDF,0xFF,0xBF,0xFF,0xDF,0xFE,0xFB,0xFF,0xFF,0xFF,0xFF,0x10,0xC0,0x08,0x00,0x00,0x0F,0xFF,0xBF,0xFF,0x80,0x00,0x00,0x07,0xFF,0xFF,0xFF,0xE8,0x80,0x7F,0xFF,0xFF,0xF3,0xFF,0xBF,0xFF,0x7F,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xE1,0xC0,0x7F,0xFF,0xFF,0xFC,0x7E,0x5F,0xF8,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xF0,0x00,0xFF,0xFF,0xFF,0xFF,0x81,0xE0,0x07,0xFF,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,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,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,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,0xFF,0xFF,0xFF,0xFF,0xFF};#define delayNOP0(); {_nop_();_nop_();};#define delayNOP1(); {_nop_();_nop_();_nop_();_nop_();};void delay(int In,int Out) {int i,j;for(i=0;i<In;i++){for(j=0;j<Out;j++){;}}}/*******************************************************************//*检查LCD忙状态 *//*lcd_busy为1时,忙,等待。
12864液晶显示图片原理(完整版)

51单片机综合学习12864液晶原理分析1辛勤学习了好几天,终于对12864液晶有了些初步了解~没有视频教程学起来真有些累,基本上内部程序写入顺序都是根据程序自我变动,然后逆向反推出原理……芯片:YM12864R P-1 控制芯片:ST7920A 带中文字库初步小结:1、控制芯片不同,寄存器定义会不同2、显示方式有并行和串行,程序不同3、含字库芯片显示字符时不必对字符取模了4、对芯片的结构地址一定要理解清楚5、显示汉字时液晶芯片写入数据的顺序(即显示的顺序)要清楚6、显示图片时液晶芯片写入数据的顺序(即显示的顺序)要清楚7、显示汉字时的二级单元(一级为八位数据写入单元)要清楚8、显示图片时的二级单元(一级为八位数据写入单元)要清楚 12864点阵液晶显示模块(LCM)就是由128*64个液晶显示点组成的一个128列*64行的阵列。
每个显示点对应一位二进制数,1表示亮,0表示灭。
存储这些点阵信息的RAM 称为显示数据存储器。
要显示某个图形或汉字就是将相应的点阵信息写入到相应的存储单元中。
图形或汉字的点阵信息由自己设计,问题的关键就是显示点在液晶屏上的位置(行和列)与其在存储器中的地址之间的关系。
由于多数液晶显示模块的驱动电路是由一片行驱动器和两片列驱动器构成,所以12864液晶屏实际上是由左右两块独立的64*64液晶屏拼接而成,每半屏有一个512*8 bits显示数据RAM。
左右半屏驱动电路及存储器分别由片选信号CS1和CS2选择。
显示点在64*64液晶屏上的位置由行号(line,0~63)与列号(column,0~63)确定。
512*8 bits RAM中某个存储单元的地址由页地址(Xpage,0~7)和列地址(Yaddress,0~63)确定。
每个存储单元存储8个液晶点的显示信息。
为了使液晶点位置信息与存储地址的对应关系更直观关,将64*64液晶屏从上至下8等分为8个显示块,每块包括8行*64列个点阵。
LCD12864液晶的使用之字库型液晶(二)

Read_L=ReadByte(); //读低8位
write_LCD_command(ROW+0x80); //送入垂直地址
write_LCD_command(xlabel+0x80);//再送入水平地址
if(xlabel_bit<8)
{
switch(color)
address++;//指针地址指向下个位置
}
}
}
还有一点要注意的就是显示图片和显示ASCII码、汉字的初始化函数不同,显示图片用的是扩展指令:
void init_BMP()
{
write_LCD_command(0x36);//CL=1--8位。扩充指令(RE=1),绘图打开(G=1)
delay(100);//适当延时
下面这个显示温度曲线:
这两个的仿真图大家可以做一下!
/echoas/blog/item/525d2f74bc735508b151b92d.html
{
ROW=y;
}
else//显示的是下半屏
{
ROW=y-32;
xlabel+=8; //规定显示在下半屏
}
write_LCD_command(ROW+0x80); //送入垂直地址
write_LCD_command(xlabel+0x80);//再送入水平地址
ReadByte();//读取当前GDRAM数据前腰进行一次空读,接下来就可以读出数据了
break;
default:break;
}
write_LCD_data(Read_H);//将数据写入GDRAM
带子库12864绘图说明

带字库12864绘图说明一、用带字库12864LCD屏绘图首先要对其绘图寄存器GDRAM地址了解清楚。
如图所示绘图寄存器GDRAM地址由水平地址(LCD_X)和垂直地址(LCD_Y)组成;如上图所示,水平地址共有16个(0x80~0x8f),其中上半屏起始地址为0X80,下半屏起始地址为0X88每个水平地址对应16列,上下半屏各有8个水平地址,所以一屏总共有128列.垂直地址共有32个(0x80~0x9f),因为上下半屏的垂直地址一样所以实际上一屏总共有64行。
特别注意:虽然一屏有128列,但并不是每列都有它的地址。
其实,从左往右每16列为一“大列”,有一个水平地址。
送数据时只要将该“大列”的水平地址和垂直地址送入12864,然后紧接这写如两个字节的内容,就可将这两个字节的内容显示在这一“大列”的16位上(先送高位,再送低位;显示时左面8位为高位)。
二、写入绘图RAM的步骤按照上面的步骤写了一个绘图地址的函数void wr_address( void)//送地址函数{write_com(0x34);//附加功能使能write_com(LCD_Y);//送入垂直地址write_com(LCD_X);//送入水平地址write_com(0x30);//禁止附加功能}下面是一个清屏函数(注意:绘图的清屏与显示汉字的清屏不同,手册中的清屏指令只能清楚DDRAM的内容,但无法清楚GDRAM的内容。
绘图清屏其实就是向GDRAM中写如0x00)void show3(void)//绘图清屏{uchar i,j,k;LCD_X=0X80;for(i=0;i<2;i++){LCD_Y=0X80;for(j=0;j<32;j++){wr_address();//写入起始地址for(k=0;k<16;k++)//连续写入16个字节(一行写满),每写入两个字节LCD_X会自动加1write_data(0x00);LCD_Y++;//垂直地址不会自动加1,写完一行后要程序换行}LCD_X=0X88;}write_com(0x36);write_com(0x30);}三、用带字库的LCD屏显示波形实例A、大致步骤1、绘图清屏2、AD转换器对波形采样,并将采样值定义在0~63之间,依次存入容量为128字节的一个数组中3、从数组中依次取出数据,送入GDRAMB、设计难点1、如何在屏上显示高低不同的点2、如何将不规则、无规律的点用字节的形式送显示3、怎样用AD转换的结果来控制显示的波形C、解决方案1、本次设计的核心思想就是将LCD屏看作一个128*64的点阵屏,从左往右循环送入uint code tab2[]={0x8000,0x4000,0x2000,0x1000,0x0800,0x0400,0x0200,0x0100,0x0080,0x0040,0x0020,0x0010,0x0008,0x0004,0x0002,0x000 1};的内容,这些点的高低由它们的垂直坐标LCD_Y决定;我们用AD 转换结果的128个字节的内容与128列一一对应,这写结果作为它们对应列上点的垂直坐标(注意,这些结果还要少做处理后才能作为垂直坐标,具体见下面程序)2、上面的做法会出现一个问题,那就是在一个“大列”中(一个水平坐标内)的16个点如果在同一行上出现两个以上的点,那么前面的点将不会显示(例如,在水平地址为0x80的这一“大列”中,第一列和第三列同在第三行,那么在显示第一列的点时地址为(0x80,0x82)的GDRAM中送入的数据是0x8000,而在显示第三列时,该GDRAM要送入的数据为0x2000;最终该GDRAM为0x2000,所以第一列的点在屏上就显示不出来了)。
12864显示汉字,图型,任意点,任意直线程序(绝对能用)

#include<stdio.h>#include<reg52.h>#include<math.h>#include<intrins.h>sbit RS=P0^0;sbit RW=P0^1;sbit E=P0^2;sbit PSB=P0^3;sbit RES=P0^4;#define LCD12864_DatePort P2unsigned char lcd_x,lcd_y;unsigned char h[]={"aaaaaaaaaaaaaaaa"};unsigned char code image[1024]={0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x06,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x0B,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x08,0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x10,0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x20,0xC0,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x01,0xFF,0xE0,0x00,0x00,0x00,0x1F,0xC1,0xC0,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x07,0xFF,0xF8,0x00,0x00,0x00,0xFF,0xC0,0xC0,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x1F,0xFF,0xFC,0x00,0x00,0x01,0xFF,0xFE,0x1F,0x80,0x00,0x00,0x00,0x00, 0x00,0x00,0x3F,0xFF,0xFF,0x00,0x00,0x07,0xFF,0xFF,0x9E,0xC0,0x00,0x00,0x00,0x00, 0x00,0x00,0x7F,0xFF,0xFF,0x80,0x00,0x0F,0xFF,0xFF,0xEC,0x60,0x00,0x00,0x00,0x00, 0x00,0x00,0xFF,0xFF,0xFF,0xC0,0x00,0x0F,0xFF,0xFF,0xE0,0x40,0x00,0x00,0x00,0x00, 0x00,0x01,0xFF,0x3E,0x3F,0xC0,0x00,0x1F,0xE3,0xE7,0xF0,0x80,0x00,0x00,0x00,0x00, 0x00,0x01,0xFE,0x1E,0x1F,0xE0,0x00,0x3F,0xE3,0xC3,0xF9,0x00,0x00,0x00,0x00,0x00, 0x00,0x03,0xFC,0x1C,0x1F,0xE0,0x00,0x3F,0xC1,0xC3,0xFC,0x00,0x00,0x00,0x00,0x00, 0x00,0x03,0xFC,0x6D,0x9F,0xF0,0x00,0x7F,0xC1,0x81,0xFE,0x00,0x00,0x00,0x00,0x00, 0x00,0x07,0xFC,0x6D,0x8F,0xF0,0x00,0x7F,0xCD,0xB1,0xFE,0x00,0x00,0x00,0x00,0x00, 0x00,0x07,0xFC,0x6D,0x9F,0xF0,0x00,0x7F,0xCF,0xB1,0xFF,0x00,0x00,0x00,0x00,0x00, 0x00,0x07,0xFC,0x1C,0x1F,0xF0,0x00,0xFF,0xC5,0xF3,0xFF,0x00,0x00,0x00,0x00,0x00, 0x00,0x07,0xFE,0x1E,0x1F,0xF8,0x00,0xFF,0xE3,0xC3,0xFF,0x00,0x00,0x00,0x00,0x00, 0x00,0x07,0xFF,0x3E,0x3F,0xF8,0x00,0xFF,0xE3,0xE7,0xFF,0x00,0x00,0x00,0x00,0x00, 0x00,0x0F,0xFF,0xF3,0xFF,0xF8,0x00,0xFF,0xFE,0x7F,0xFF,0x80,0x00,0x00,0x00,0x00,0x00,0x0F,0xF8,0xC1,0xCF,0xFC,0x00,0xFF,0x9C,0x38,0xFF,0x80,0x00,0x00,0x00,0x00, 0x00,0x0F,0xE0,0x7F,0x83,0xFC,0x01,0xFE,0x0F,0xF0,0x3F,0x80,0x00,0x00,0x00,0x00, 0x00,0x1F,0xFF,0x00,0x3F,0xFC,0x01,0xFF,0xE0,0x07,0xFF,0x80,0x00,0x00,0x00,0x00, 0x00,0x1F,0xFF,0xFB,0xFF,0xFC,0x01,0xBF,0xFF,0xFF,0xFF,0x80,0x00,0x00,0x00,0x00, 0x00,0x1F,0xFF,0xFF,0xFF,0xFC,0x01,0xDF,0xFF,0xFF,0xFB,0x80,0x00,0x00,0x00,0x00, 0x00,0x3F,0xFF,0xFF,0xFF,0xFC,0x03,0xC7,0xFF,0xFF,0xE7,0x80,0x00,0x00,0x00,0x00, 0x00,0x7F,0xFF,0xFF,0xFF,0xFC,0x07,0xC1,0xFF,0xFF,0x8F,0xC0,0x00,0x00,0x00,0x00, 0x00,0xFF,0xFF,0xFF,0xFF,0xFE,0x0F,0xE0,0x3F,0xFC,0x3F,0xC0,0x00,0x00,0x00,0x00, 0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0x1F,0xF8,0x00,0x00,0x7F,0xE0,0x00,0x00,0x00,0x00, 0x01,0xFC,0x7F,0xFF,0xFF,0x3F,0x1F,0x8E,0x00,0x00,0xE3,0xF0,0x00,0x00,0x00,0x00, 0x03,0xF8,0x7F,0xFF,0xFC,0x1F,0xBF,0x87,0xC8,0x1F,0x83,0xF0,0x00,0x00,0x00,0x00, 0x03,0xF8,0x7F,0xFF,0xE0,0x1F,0xFF,0x87,0xFF,0xFC,0x01,0xF8,0x00,0x00,0x00,0x00, 0x03,0xF8,0x7F,0x00,0x00,0x1F,0xFF,0x04,0xE0,0x00,0x01,0xF8,0x00,0x00,0x00,0x00, 0x07,0xF8,0x7F,0x00,0x00,0x0F,0xFF,0x04,0x60,0x00,0x01,0xF8,0x00,0x00,0x00,0x00, 0x07,0xF8,0x7F,0x00,0x00,0x0F,0xFF,0x0C,0x60,0x00,0x01,0xFC,0x00,0x00,0x00,0x00, 0x07,0xF8,0x7F,0x00,0x00,0x0F,0xFF,0x0C,0x60,0x00,0x01,0xFC,0x00,0x00,0x00,0x00, 0x07,0xF8,0x7F,0x00,0x00,0x0F,0xFF,0x06,0x60,0x00,0x01,0xFC,0x00,0x00,0x00,0x00, 0x07,0xB8,0x3E,0x00,0x00,0x19,0xF3,0x87,0xE0,0x00,0x01,0xBC,0x00,0x00,0x00,0x00, 0x07,0x18,0x00,0x00,0x00,0x18,0xE3,0x80,0x00,0x00,0x01,0x18,0x00,0x00,0x00,0x00, 0x00,0x1C,0x00,0x00,0x00,0x10,0x01,0x80,0x00,0x00,0x03,0x00,0x00,0x00,0x00,0x00, 0x00,0x0C,0x00,0x00,0x00,0x30,0x01,0xC0,0x00,0x00,0x02,0x00,0x00,0x00,0x00,0x00, 0x00,0x06,0x00,0x00,0x00,0x60,0x00,0xE0,0x00,0x00,0x04,0x00,0x00,0x00,0x00,0x00, 0x00,0x03,0x00,0x00,0x00,0x40,0x00,0x70,0x00,0x00,0x0C,0x00,0x00,0x00,0x00,0x00, 0x00,0x03,0x80,0x00,0x00,0xC0,0x00,0x78,0x00,0x00,0x1C,0x00,0x00,0x00,0x00,0x00, 0x00,0x0D,0xE0,0x00,0x03,0xB8,0x01,0x9C,0x00,0x00,0x3B,0x00,0x00,0x00,0x00,0x00, 0x00,0x18,0x78,0x00,0x0F,0x7C,0x03,0xCF,0x00,0x00,0xE7,0x80,0x00,0x00,0x00,0x00, 0x00,0x10,0x1C,0x00,0x3E,0xFC,0x03,0xF3,0xE0,0x03,0xDF,0x80,0x00,0x00,0x00,0x00, 0x00,0x1A,0x0B,0xC1,0xE3,0xF8,0x01,0xF8,0xFC,0x3F,0x3F,0x00,0x00,0x00,0x00,0x00, 0x00,0x0F,0xF1,0x80,0xEF,0xE0,0x00,0x7F,0xF0,0x1F,0xFC,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, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};void delay_ms(unsigned char z) //延时{unsigned i,j;for(i=0;i<z;i++)for(j=0;j<110;j++);}void LCD12864_WriteCmd(unsigned int cmd) //写命令{RS=0;RW=0;E=0;LCD12864_DatePort=cmd;delay_ms(5);E=1;delay_ms(5);E=0;}void LCD12864_WriteDate(unsigned char dat) //写数据{RS=1;RW=0;E=0;LCD12864_DatePort=dat;delay_ms(5);E=1;delay_ms(5);E=0;}void LCD12864_Init(){PSB=1; //1并行,0串行LCD12864_WriteCmd(0x30); //基本指令操作//delay_ms(5);LCD12864_WriteCmd(0x0c); //显示开,关光标//delay_ms(5);LCD12864_WriteCmd(0x01); //清除led的显示内容//delay_ms(5);LCD12864_WriteCmd(0x06);}/*====================================================函数功能:清除GCROM的内容,如果不清除会出现花屏现象清除方法:向GCROM中写入0x00来清除内========================================================*/ void LCD12864_ClearGDRAM(){unsigned char i,j,k;lcd_x=0x80;lcd_y=0x80;LCD12864_WriteCmd(0x34);for(i=0;i<2;i++){for(j=0;j<32;j++){LCD12864_WriteCmd(lcd_y+j);LCD12864_WriteCmd(lcd_x);for(k=0;k<16;k++){LCD12864_WriteDate(0x00);}}lcd_x=0x88;}LCD12864_WriteCmd(0x36);LCD12864_WriteCmd(0x30);}/*================================================================ 函数功能:向12864中写入一幅图片函数参数:lcd_x为水平显示位置,lcd_y为垂直显示位置,函数将12864屏分成上下两屏写入,上半屏LCD_x=0x80,下半屏lcd_x=0x88=================================================================*/ void LCD12864_WriteImage(unsigned char *p){unsigned char i,j,k;lcd_x=0x80;lcd_y=0x80;LCD12864_WriteCmd(0x34);for(i=0;i<2;i++) //分为上下两屏{for(j=0;j<32;j++){LCD12864_WriteCmd(lcd_y+j);LCD12864_WriteCmd(lcd_x);for(k=0;k<16;k++) //写入显示数据{LCD12864_WriteDate(*p++);}}lcd_x=0x88;}LCD12864_WriteCmd(0x36);LCD12864_WriteCmd(0x30);}bit LCD12864_CheckBusy() //读忙碌状态{bit i;RS=0;RW=1;E=1;LCD12864_DatePort=0xff;delay_ms(1);i=(bit)(LCD12864_DatePort&0x80);E=0;return(i);}unsigned char LCD12864_ReadByte( void ){unsigned char ReturnValue ;LCD12864_CheckBusy() ;LCD12864_DatePort = 0xff ;RS=1;RW=1;E=0;E=1;ReturnValue =LCD12864_DatePort;E=0;return ReturnValue ;}void LCD12864_DrawPoint( unsigned char X, unsigned char Y, unsigned char Color ) {unsigned char Row , Tier , Tier_bit ;unsigned char ReadOldH, ReadOldL ;LCD12864_WriteCmd( 0x34 ) ;LCD12864_WriteCmd( 0x36 ) ;Tier = X >> 4 ;Tier_bit = X & 0x0f ;if( Y < 32 ){Row = Y ;}else{Row = Y - 32 ;Tier += 8 ;}LCD12864_WriteCmd( Row + 0x80 ) ;LCD12864_WriteCmd( Tier + 0x80 ) ;LCD12864_ReadByte();ReadOldH = LCD12864_ReadByte() ;ReadOldL = LCD12864_ReadByte() ;LCD12864_WriteCmd( Row + 0x80 ) ;LCD12864_WriteCmd( Tier + 0x80 ) ;if( Tier_bit < 8 ){switch( Color){case 0 : ReadOldH &=( ~( 0x01 << ( 7 - Tier_bit ))) ; break ;case 1 : ReadOldH |= ( 0x01 << ( 7 - Tier_bit )) ; break ;case 2 : ReadOldH ^= ( 0x01 << ( 7 - Tier_bit )) ; break ;default : break ;}LCD12864_WriteDate( ReadOldH ) ;LCD12864_WriteDate( ReadOldL ) ;}else{switch(Color){case 0 : ReadOldL &= (~( 0x01 << ( 15 - Tier_bit ))) ; break ;case 1 : ReadOldL |= ( 0x01 << ( 15 - Tier_bit )) ; break ;case 2 : ReadOldL ^= ( 0x01 << ( 15 - Tier_bit )) ; break ;default : break ;}LCD12864_WriteDate( ReadOldH ) ;LCD12864_WriteDate( ReadOldL ) ;}LCD12864_WriteCmd( 0x30 ) ;}void LCD12864_DrawLine_X( unsigned char X0, unsigned char X1, unsigned char Y, unsigned char Color ){ unsigned char Temp ;if( X0 > X1 ){Temp = X1 ;X1 = X0 ;X0 = Temp ;}for( ; X0 <= X1 ; X0++ )LCD12864_DrawPoint( X0, Y, Color ) ;}void LCD12864_DrawLine_Y( unsigned char X, unsigned char Y0, unsigned char Y1, unsigned char Color ){unsigned char Temp ;if( Y0 > Y1 ){Temp = Y1 ;Y1 = Y0 ;Y0 = Temp ;}for(; Y0 <= Y1 ; Y0++)LCD12864_DrawPoint( X, Y0, Color) ;}void LCD12864_DrawLine( unsigned char StartX, unsigned char StartY, unsigned char EndX, unsigned char EndY, unsigned char Color ){int t, distance; /*根据屏幕大小改变变量类型(如改为int型)*/int x = 0 , y = 0 , delta_x, delta_y ;char incx, incy ;delta_x = EndX - StartX ;delta_y = EndY - StartY ;if( delta_x > 0 ){incx = 1;}else if( delta_x == 0 ){LCD12864_DrawLine_Y( StartX, StartY, EndY, Color ) ;return ;}else{incx = -1 ;}if( delta_y > 0 ){incy = 1 ;}else if(delta_y == 0 ){LCD12864_DrawLine_X( StartX, EndX, StartY, Color ) ;return ;}else{incy = -1 ;}delta_x = abs( delta_x );//求绝对值delta_y = abs( delta_y );if( delta_x > delta_y ){distance = delta_x ;}else{distance = delta_y ;}LCD12864_DrawPoint( StartX, StartY, Color ) ;/* Draw Line*/for( t = 0 ; t <= distance+1 ; t++ ){LCD12864_DrawPoint( StartX, StartY, Color ) ;x += delta_x ;y += delta_y ;if( x > distance ){x -= distance ;StartX += incx ;}if( y > distance ){y -= distance ;StartY += incy ;}}}void LCD12864_DrawCross(){LCD12864_DrawLine_X( 0, 127 , 0, 1 ) ;LCD12864_DrawLine_X( 0, 127 , 7, 1 ) ;LCD12864_DrawLine_X( 0, 127 , 15, 1 ) ;LCD12864_DrawLine_X( 0, 127 , 23, 1 ) ;LCD12864_DrawLine_X( 0, 127 , 31, 1 ) ;LCD12864_DrawLine_X( 0, 127 , 39, 1 ) ;LCD12864_DrawLine_X( 0, 127 , 47, 1 ) ;LCD12864_DrawLine_X( 0, 127 , 55, 1 ) ;LCD12864_DrawLine_X( 0, 127 , 63, 1 ) ;LCD12864_DrawLine_Y( 0, 0 , 63, 1 ) ;LCD12864_DrawLine_Y( 15, 0 , 63, 1 ) ;LCD12864_DrawLine_Y( 31, 0 , 63, 1 ) ;LCD12864_DrawLine_Y( 47, 0 , 63, 1 ) ;LCD12864_DrawLine_Y( 63, 0 , 63, 1 ) ;LCD12864_DrawLine_Y( 79, 0 , 63, 1 ) ;LCD12864_DrawLine_Y( 95, 0 , 63, 1 ) ;LCD12864_DrawLine_Y( 111, 0 , 63, 1 ) ;LCD12864_DrawLine_Y( 127, 0 , 63, 1 ) ;}void LCD12864_Draw_ObliqueLine(){LCD12864_DrawLine( 0, 0, 127, 63, 1 ) ;LCD12864_DrawLine( 0, 63, 127, 0 , 1 ) ;LCD12864_DrawLine( 12, 0, 127, 63, 1 ) ;LCD12864_DrawLine( 52, 63, 127, 0 , 1 ) ;LCD12864_DrawLine( 32, 63, 98, 0, 1 ) ;LCD12864_DrawLine( 67, 0, 127, 63 , 1 ) ;}void LCD12864_DisplayOneChar(unsigned char X, unsigned char Y, unsigned char Data) {switch(Y){case 0:Y=0X80;break; //根据行数来选择相应地址case 1:Y=0X90;break;case 2:Y=0X88;break;case 3:Y=0X98;break;}LCD12864_WriteCmd( Y+X ); //这里不检测忙信号,发送地址码LCD12864_WriteDate(Data);}void LCD12864_DisplayListChar(unsigned char X, unsigned char Y, unsigned char *Data) {switch(Y){case 0:Y=0X80;break; //根据行数来选择相应地址case 1:Y=0X90;break;case 2:Y=0X88;break;case 3:Y=0X98;break;}LCD12864_WriteCmd( Y+X ); //这里不检测忙信号,发送地址码X = X*2;Y = 0;while( Data[Y] != 0 ) //若到达字串尾则退出{if (X <= 0x0F) //X坐标应小于0xF{LCD12864_WriteDate(Data[Y]);X++;Y++;}else break;}}void main(){LCD12864_Init();// write_com(0x1c);LCD12864_ClearGDRAM();//LCD12864_WriteImage(image);//LCD12864_Draw_ObliqueLine();LCD12864_DrawCross();//LCD12864_DisplayListChar(0,0,h);while(1);}。
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最近买了一块12864液晶显示屏,淘宝给我的资料不算多,我就从网上下载了部分资料,通过研究别人的例程我发现了一些问题,并得出了自己的见解。
写程序一定要严谨,同时又要求精练,如果程序中多了些没用的语句不仅让学习的人看的一头雾水,而且又占用多余的空间,我想通过自己的实践来鄙视那些程序不严谨就挂到网上的人,给初学者很多困惑。
我就通过12864的绘图功能来说下,不对之处望求指正(附上绘图说明)
12864(ST7920驱动芯片)把屏幕分成上下两部分(如上图中把垂直坐标分成了两部分的00~1F)。
水平坐标00到0F处于同一面,而不是上下屏的关系,[上半屏“07”后通过我标注的箭头连接是到下一个红色00行]。
在向GDRAM中写入要显示的图片时,我们先指定从X:00、Y:00处(也就是第①处)开始写入数据,我们先在第①处写图形数据(按照图片所标注,第15位在最左边,第0位在最右边,即在写入的时候LCD会先写高位字节,接着再写低位字节),接着LCD会自动把坐标定位到同一行第②处的开头,此时我们可以接着告诉LCD在这里写入图形数据,依此类推,当我们写满16次后,第00行(包括上半屏和下半屏的)就全写满了。
那么我们接下去写入数据会出现什么情况呢?接着LCD又自动从第00行的第①处重新开始写了。
这是因为ST7920控制芯片设计出来就这样,在写入的时候它只会在水平方向(X轴上)地址自增,并且在增加到0F地址之后就会变成00地址从头开始写。
从这里我们可以明白,每次写满一行(共16部分)后就必须在程序里人为地把垂直方向(Y轴)的地址加1,不然就会造成只是在同一行重复写入的现象。
垂直(列)地址由AC6~AC0指定,共32行,列地址由AC3AC2AC1AC0指定,共16列(00-0F),绘图程序如下:
通过以上所讲我想大家也明白了很多了吧,我看网上有很多教程说是要把屏幕分开两半来写程序,其实我觉得下半屏程序根本没必要再写出来,因为见上面的分析过程,其实“上半部分屏”程序已经完全把整个屏幕覆盖了,而下半部分屏相当于在原来的基础上又
重新覆盖了一部分。
比如写第一行范围是00-0F,而下半部分屏第一行是从08-0F(重复部分就是08-0F),所以我把下半部分注释掉了,通过烧录进单片机发现绘出的图像依然一样,验证了我的想法。