【原理】从零编写ILI9341驱动全过程（基于Arduino）
作者：互联网
最近在淘宝入手了一块ILI9341彩色屏幕，支持320x240分辨率。之前一直很好奇这类单片机驱动的彩色屏幕的原理，就打算自己写一个驱动，从电流层面操控ILI9341屏幕。话不多说，我们开始吧(￣▽￣)~*
1.ILI9341芯片和ILI9341驱动板
首先这里要明确两个概念，ILI9341芯片和ILI9341驱动板。
ILI9341芯片是ilitek发布的液晶驱动芯片，是这个样子的：
而淘宝上的ILI9341驱动板是把ILI9341芯片、屏幕和针脚焊接在一起的电路板，它可能是这个样子的：
也可能是这个样子的：
还可能是这个样子的：
没错，不同的厂家可以制造不同形状，不同接口的ILI9341驱动板，但他们上面都有ILI9341芯片，所以我们可以用相同的方法操作它。
2.如何操作它呢？
这是ILI9341驱动板的背面，我在上面做了些标注，应该会方便理解些。我们只要控制这些针脚的通电与否（高电平与低电平），就能够获得操控这块屏幕的“完整权限”！那这些针脚的定义是什么呢？我们一个一个看：
左上角有五个最重要的针脚，分别是LCD_RST、LCD_CS、LCD_RS、LCD_WR和LCD_RD：（直接用文字写不能冒号对齐，没办法，开个代码框(￣▽￣)~*）
LCD_RST ： 即LCD Reset，用于在通电之后复位，初始化整个模块。 LCD_CS ： 即LCD Chip Select，用于多个芯片之间的片选操作。由于这块驱动板只有一个可用的芯片，所以一般该针脚不通电。 LCD_RS ： 又称D/CX信号线，用于切换写命令（Command）和写数据（Data），当对显示屏写命令（Command）时，应该让针脚不通电，当对显示屏写数据（Data）时，应该让针脚通电。 LCD_WR ： 写使能。当LCD_WR不通电，并且LCD_RD通电时，数据传输方向为写入。 LCD_RD ： 读使能。
左下角的针脚负责供电，不细讲。
右上角的LCD_D0到LCD_D7是数据脚，通过控制它的通电与否来传输8个比特，也就是8个0或1。这种方式可以传输一个最小值0，最大值255的数字，我们用它来传输所有命令和数据。
右下角的SD_SS,SD_DI,SD_D0,SD_SCK适用于控制SD卡读写的，不属于ILI9341的范畴，我们先不讨论。
那么，如何操作它呢？这张图能够很清楚的说明：（下面用拉低代表示不通电，拉高表示通电，这样术语会更加标准）
- 单片机开机，ILI9341驱动板接收到电流，开始进入待命状态
- 拉低LCD_CS片选信号，选择对ILI9341芯片发送命令
- 通过拉高拉低LCD_D0到LCD_D7数据脚，来表示二进制数据
- 拉低拉高LCD_RS针脚来告诉机器这是一个命令，还是一个数据
- 拉低LCD_WR，进行写使能（可以理解为按下回车键，把LCD_D0到D7的数据发送出去）
这就是发送一个命令或者数据的方法。二进制，十进制和十六进制的转换和表达先直接略过，如果要展开，那可能可以出一本书了( • ̀ω•́ )✧，关于LCD_D0到D7脚应该发送什么，ILITEK在设计ILI9341时就已经规定好了，中文文档在此：
接下来，就是，愉快的，编码时间啦( • ̀ω•́ )✧！！！
3.兼容性设定
不知刚才你有没有注意到数据脚是从LCD_D2开始的？那是因为Arduino Uno开发板的第0和1脚是USB针脚，不能被使用，只能从第2个针脚开始设计：
那我们在编程时要用到LCD_D0和LCD_D1时，就必须写成8和9。另外不同机器脚位也不一样，所以我用宏定义来简化程序：
#define LCD_D0 8 #define LCD_D1 9 #define LCD_D2 2 #define LCD_D3 3 #define LCD_D4 4 #define LCD_D5 5 #define LCD_D6 6 #define LCD_D7 7 #define LCD_RD A0 #define LCD_WR A1 #define LCD_RS A2 #define LCD_CS A3 #define LCD_RST A4
这样即解决了LCD_D0和LCD_D1脚的问题，还搞定的不同开发板的兼容性问题。由于#define是在预编译阶段生成的，所以不会影响代码运行的速度。
4.发送命令和数据
调用这块屏幕的方法很明确，就是写入2进制数字。通过设计厂商提供的命令表发送相应的2进制命令和数据，实现操控。这样做的好处是无论你使用的是什么机器，什么驱动板，只要实现了LcdWriteCommand()和LcdWriteData()两个函数，就可以实现对屏幕的完全控制。
你当然可以用最直接的办法去控制引脚，比如digitalWrite():
void LcdWriteCommand(unsigned char d){
//Write Command Mode On
digitalWrite(LCD_RS,LOW);
//Write Datas to LCD_D0 to LCD_D7
digitalWrite(LCD_D0,d%2);
d = d >> 1;
digitalWrite(LCD_D1,d%2);
d = d >> 1;
digitalWrite(LCD_D2,d%2);
d = d >> 1;
digitalWrite(LCD_D3,d%2);
d = d >> 1;
digitalWrite(LCD_D4,d%2);
d = d >> 1;
digitalWrite(LCD_D5,d%2);
d = d >> 1;
digitalWrite(LCD_D6,d%2);
d = d >> 1;
digitalWrite(LCD_D7,d%2);
d = d >> 1;
//Enable Datas
digitalWrite(LCD_WR,LOW);
digitalWrite(LCD_WR,HIGH);
}
void LcdWriteData(unsigned char d){
//Write Data Mode On
digitalWrite(LCD_RS,HIGH);
//Write Datas to LCD_D0 to LCD_D7
digitalWrite(LCD_D0,d%2);
d = d >> 1;
digitalWrite(LCD_D1,d%2);
d = d >> 1;
digitalWrite(LCD_D2,d%2);
d = d >> 1;
digitalWrite(LCD_D3,d%2);
d = d >> 1;
digitalWrite(LCD_D4,d%2);
d = d >> 1;
digitalWrite(LCD_D5,d%2);
d = d >> 1;
digitalWrite(LCD_D6,d%2);
d = d >> 1;
digitalWrite(LCD_D7,d%2);
d = d >> 1;
//Enable Datas
digitalWrite(LCD_WR,LOW);
digitalWrite(LCD_WR,HIGH);
}
但是这样做的话，速度嘛。。。看看这个，你就不会想用digitalWrite了：
单片机中，速度为王，我们还是直接改Register吧：
void LcdWriteCommand(unsigned char d){
//Write Command Mode On
fastDigitalWriteLOW(LCD_RS);
//Write Datas to LCD_D0 to LCD_D7
PORTD = (PORTD & B00000011) | ((d) & B11111100);
PORTB = (PORTB & B11111100) | ((d) & B00000011);
//Enable Datas
fastDigitalWriteLOW(LCD_WR);
fastDigitalWriteHIGH(LCD_WR);
}
void LcdWriteData(unsigned char d){
//Write Command Mode On
fastDigitalWriteHIGH(LCD_RS);
//Write Datas to LCD_D0 to LCD_D7
PORTD = (PORTD & B00000011) | ((d) & B11111100);
PORTB = (PORTB & B11111100) | ((d) & B00000011);
//Enable Datas
fastDigitalWriteLOW(LCD_WR);
fastDigitalWriteHIGH(LCD_WR);
}
这段代码中，我用了宏定义来实现fastDigitalWriteHIGH()和fastDigitalWriteLOW()，这两个定义能避免函数的栈调用。其实用内联函数来写也可以实现：
inline void fastDigitalWriteHIGH(int Pin){
*(portOutputRegister(digitalPinToPort(Pin)))|=digitalPinToBitMask(Pin);
return;
}
但我就是喜欢宏定义，而且宏定义行数少些。
另外你可能会疑惑：什么是PORTB和PORTD？
PORTB其实就是针脚8-13，PORTD其实就是针脚0-7：
假如你有一个这样的二进制数：
00000100
把他转换成十进制：
4
再把它赋值给PORTD
PORTD = 4;
你就会发现针脚2通电了（图中连接到左边第一个红色灯泡）：
这就是PORTD的真正意义，它使用一个从0到255的数，记录针脚0到7的通电情况。
那我们为什么不用digitalWrite()，而是要用PORTB和PORTD呢？因为快啊(￣▽￣)~*
5.Enjoy!
我们刚刚实现了LcdWriteCommand()和LcdWriteData()两个函数，现在，我们就可以实现对屏幕的完全控制了！
首先，先运行一段初始化命令：
//Initialize Data Pins
pinMode(LCD_D0,OUTPUT);
pinMode(LCD_D1,OUTPUT);
pinMode(LCD_D2,OUTPUT);
pinMode(LCD_D3,OUTPUT);
pinMode(LCD_D4,OUTPUT);
pinMode(LCD_D5,OUTPUT);
pinMode(LCD_D6,OUTPUT);
pinMode(LCD_D7,OUTPUT);
//Initialize Command Pins
pinMode(LCD_RD,OUTPUT);
pinMode(LCD_WR,OUTPUT);
pinMode(LCD_RS,OUTPUT);
pinMode(LCD_CS,OUTPUT);
pinMode(LCD_RST,OUTPUT);
digitalWrite(LCD_CS,LOW);
digitalWrite(LCD_RD,HIGH);
digitalWrite(LCD_WR,LOW);
//Reset
digitalWrite(LCD_RST,HIGH);
delay(5);
digitalWrite(LCD_RST,LOW);
delay(15);
digitalWrite(LCD_RST,HIGH);
delay(15);
LcdWriteCommand(0xCB);
LcdWriteData(0x39);
LcdWriteData(0x2C);
LcdWriteData(0x00);
LcdWriteData(0x34);
LcdWriteData(0x02);
LcdWriteCommand(0xCF);
LcdWriteData(0x00);
LcdWriteData(0XC1);
LcdWriteData(0X30);
LcdWriteCommand(0xE8);
LcdWriteData(0x85);
LcdWriteData(0x00);
LcdWriteData(0x78);
LcdWriteCommand(0xEA);
LcdWriteData(0x00);
LcdWriteData(0x00);
LcdWriteCommand(0xED);
LcdWriteData(0x64);
LcdWriteData(0x03);
LcdWriteData(0X12);
LcdWriteData(0X81);
LcdWriteCommand(0xF7);
LcdWriteData(0x20);
LcdWriteCommand(0xC0); //Power control
LcdWriteData(0x23); //VRH[5:0]
LcdWriteCommand(0xC1); //Power control
LcdWriteData(0x10); //SAP[2:0];BT[3:0]
LcdWriteCommand(0xC5); //VCM control
LcdWriteData(0x3e); //Contrast
LcdWriteData(0x28);
LcdWriteCommand(0xC7); //VCM control2
LcdWriteData(0x86); //--
LcdWriteCommand(0x36); // Memory Access Control
LcdWriteData(0x48);
LcdWriteCommand(0x3A);
LcdWriteData(0x55);
LcdWriteCommand(0xB1);
LcdWriteData(0x00);
LcdWriteData(0x18);
LcdWriteCommand(0xB6); // Display Function Control
LcdWriteData(0x08);
LcdWriteData(0x82);
LcdWriteData(0x27);
LcdWriteCommand(0x11); //Exit Sleep
delay(120);
LcdWriteCommand(0x29); //Display on
LcdWriteCommand(0x2c);
这么多！不要怕，原样复制过去运行就好。这段命令是按照ILITEK设计文档中的规则发送的，用于初始化屏幕。运行完这段命令之后，我们就可以开始发自己的命令了。
我们试着来清一下屏。清屏就是指定一块区域，然后给屏幕每一个像素点的颜色为白色，这样就好了。
首先定义我们要写入的区域，这里就是从(0,0)写入到(239,319)：
int x1 = 0; int x2 = 239; int y1 = 0; int y2 = 319;
接着通知屏幕我们要写入的区域的X坐标的起始、终止位置（命令0x2a）：
LcdWriteCommand(0x2a);
然后发送X坐标的起始位置（x1），和X坐标的终止位置（x2）。我们的机器一次只能发送八位数字，但八位数字最大只能表示255，所以我们要分两次发送，先发送前八位，再发送后八位：
LcdWriteData(x1>>8); LcdWriteData(x1); LcdWriteData(x2>>8); LcdWriteData(x2);
Y坐标也是一样，只是把通知命令改成0x2b：
LcdWriteCommand(0x2b); LcdWriteData(y1>>8); LcdWriteData(y1); LcdWriteData(y2>>8); LcdWriteData(y2);
接着，我们发送开始写入的命令（0x2c），告诉屏幕我要开始发送像素了：
LcdWriteCommand(0x2c);
最后，发送所有像素的颜色数据（Data）。里面的RGB()宏定义是我在上一篇文章实现的。另外，因为是数据，所以我们要使用LcdWriteData()：
#define RGB(r,g,b) ((b&31)+((g&63)<<5)+((r&31)<<11))
for(int i=y1;i<=y2;i++){
for(int j=x1;j<=x2;j++){
LcdWriteData(RGB(31,63,31)>>8);
LcdWriteData(RGB(31,63,31));
}
}
保存，下载。
刷屏完整代码：
// Breakout/Arduino UNO pin usage:
// LCD Data Bit : 7 6 5 4 3 2 1 0
// Uno dig. pin : 7 6 5 4 3 2 9 8
// Uno port/pin : PD7 PD6 PD5 PD4 PD3 PD2 PB1 PB0
// Mega dig. pin: 29 28 27 26 25 24 23 22
#define LCD_D0 8
#define LCD_D1 9
#define LCD_D2 2
#define LCD_D3 3
#define LCD_D4 4
#define LCD_D5 5
#define LCD_D6 6
#define LCD_D7 7
#define LCD_RD A0
#define LCD_WR A1
#define LCD_RS A2
#define LCD_CS A3
#define LCD_RST A4
#define fastDigitalWriteHIGH(Pin) *(portOutputRegister(digitalPinToPort(Pin)))|=digitalPinToBitMask(Pin) //Faster digitalWrite(Pin,HIGH);
#define fastDigitalWriteLOW(Pin) *(portOutputRegister(digitalPinToPort(Pin)))&=~digitalPinToBitMask(Pin) //Faster digitalWrite(Pin,LOW);
#define RGB(r,g,b) ((b&31)+((g&63)<<5)+((r&31)<<11))
void LcdWriteCommand(unsigned char d){
//Write Command Mode On
fastDigitalWriteLOW(LCD_RS);
//Write Datas to LCD_D0 to LCD_D7
PORTD = (PORTD & B00000011) | ((d) & B11111100);
PORTB = (PORTB & B11111100) | ((d) & B00000011);
//Enable Datas
fastDigitalWriteLOW(LCD_WR);
fastDigitalWriteHIGH(LCD_WR);
}
void LcdWriteData(unsigned char d){
//Write Command Mode On
fastDigitalWriteHIGH(LCD_RS);
//Write Datas to LCD_D0 to LCD_D7
PORTD = (PORTD & B00000011) | ((d) & B11111100);
PORTB = (PORTB & B11111100) | ((d) & B00000011);
//Enable Datas
fastDigitalWriteLOW(LCD_WR);
fastDigitalWriteHIGH(LCD_WR);
}
void setup(){
//Initialize Data Pins
pinMode(LCD_D0,OUTPUT);
pinMode(LCD_D1,OUTPUT);
pinMode(LCD_D2,OUTPUT);
pinMode(LCD_D3,OUTPUT);
pinMode(LCD_D4,OUTPUT);
pinMode(LCD_D5,OUTPUT);
pinMode(LCD_D6,OUTPUT);
pinMode(LCD_D7,OUTPUT);
//Initialize Command Pins
pinMode(LCD_RD,OUTPUT);
pinMode(LCD_WR,OUTPUT);
pinMode(LCD_RS,OUTPUT);
pinMode(LCD_CS,OUTPUT);
pinMode(LCD_RST,OUTPUT);
digitalWrite(LCD_CS,LOW);
digitalWrite(LCD_RD,HIGH);
digitalWrite(LCD_WR,LOW);
//Reset
digitalWrite(LCD_RST,HIGH);
delay(5);
digitalWrite(LCD_RST,LOW);
delay(15);
digitalWrite(LCD_RST,HIGH);
delay(15);
LcdWriteCommand(0xCB);
LcdWriteData(0x39);
LcdWriteData(0x2C);
LcdWriteData(0x00);
LcdWriteData(0x34);
LcdWriteData(0x02);
LcdWriteCommand(0xCF);
LcdWriteData(0x00);
LcdWriteData(0XC1);
LcdWriteData(0X30);
LcdWriteCommand(0xE8);
LcdWriteData(0x85);
LcdWriteData(0x00);
LcdWriteData(0x78);
LcdWriteCommand(0xEA);
LcdWriteData(0x00);
LcdWriteData(0x00);
LcdWriteCommand(0xED);
LcdWriteData(0x64);
LcdWriteData(0x03);
LcdWriteData(0X12);
LcdWriteData(0X81);
LcdWriteCommand(0xF7);
LcdWriteData(0x20);
LcdWriteCommand(0xC0); //Power control
LcdWriteData(0x23); //VRH[5:0]
LcdWriteCommand(0xC1); //Power control
LcdWriteData(0x10); //SAP[2:0];BT[3:0]
LcdWriteCommand(0xC5); //VCM control
LcdWriteData(0x3e); //Contrast
LcdWriteData(0x28);
LcdWriteCommand(0xC7); //VCM control2
LcdWriteData(0x86); //--
LcdWriteCommand(0x36); // Memory Access Control
LcdWriteData(0x48);
LcdWriteCommand(0x3A);
LcdWriteData(0x55);
LcdWriteCommand(0xB1);
LcdWriteData(0x00);
LcdWriteData(0x18);
LcdWriteCommand(0xB6); // Display Function Control
LcdWriteData(0x08);
LcdWriteData(0x82);
LcdWriteData(0x27);
LcdWriteCommand(0x11); //Exit Sleep
delay(120);
LcdWriteCommand(0x29); //Display on
LcdWriteCommand(0x2c);
//Set Writing Area
int x1 = 0;
int x2 = 239;
int y1 = 0;
int y2 = 319;
LcdWriteCommand(0x2a);
LcdWriteData(x1>>8);
LcdWriteData(x1);
LcdWriteData(x2>>8);
LcdWriteData(x2);
LcdWriteCommand(0x2b);
LcdWriteData(y1>>8);
LcdWriteData(y1);
LcdWriteData(y2>>8);
LcdWriteData(y2);
//Start Writing
LcdWriteCommand(0x2c);
for(int i=y1;i<=y2;i++){
for(int j=x1;j<=x2;j++){
LcdWriteData(RGB(31,63,31)>>8);
LcdWriteData(RGB(31,63,31));
}
}
}
void loop(){
}
接下来的路线就很简单了，把指定区域的命令（0x2a,0x2b,0x2c）分装成LcdOpenWindow()函数，再实现LcdFill()函数，一个完整的ILI9341驱动就完成了：
#define LCD_D0 8
#define LCD_D1 9
#define LCD_D2 2
#define LCD_D3 3
#define LCD_D4 4
#define LCD_D5 5
#define LCD_D6 6
#define LCD_D7 7
#define LCD_RD A0
#define LCD_WR A1
#define LCD_RS A2
#define LCD_CS A3
#define LCD_RST A4
#define fastDigitalWriteHIGH(Pin) *(portOutputRegister(digitalPinToPort(Pin)))|=digitalPinToBitMask(Pin) //Faster digitalWrite(Pin,HIGH);
#define fastDigitalWriteLOW(Pin) *(portOutputRegister(digitalPinToPort(Pin)))&=~digitalPinToBitMask(Pin) //Faster digitalWrite(Pin,LOW);
#define RGB(r,g,b) ((b&31)+((g&63)<<5)+((r&31)<<11))
void LcdWriteCommand(unsigned char d){
//Write Command Mode On
fastDigitalWriteLOW(LCD_RS);
//Write Datas to LCD_D0 to LCD_D7
PORTD = (PORTD & B00000011) | ((d) & B11111100);
PORTB = (PORTB & B11111100) | ((d) & B00000011);
//Enable Datas
fastDigitalWriteLOW(LCD_WR);
fastDigitalWriteHIGH(LCD_WR);
}
void LcdWriteData(unsigned char d){
//Write Command Mode On
fastDigitalWriteHIGH(LCD_RS);
//Write Datas to LCD_D0 to LCD_D7
PORTD = (PORTD & B00000011) | ((d) & B11111100);
PORTB = (PORTB & B11111100) | ((d) & B00000011);
//Enable Datas
fastDigitalWriteLOW(LCD_WR);
fastDigitalWriteHIGH(LCD_WR);
}
void LcdInit(void){
//Initialize Data Pins
pinMode(LCD_D0,OUTPUT);
pinMode(LCD_D1,OUTPUT);
pinMode(LCD_D2,OUTPUT);
pinMode(LCD_D3,OUTPUT);
pinMode(LCD_D4,OUTPUT);
pinMode(LCD_D5,OUTPUT);
pinMode(LCD_D6,OUTPUT);
pinMode(LCD_D7,OUTPUT);
//Initialize Command Pins
pinMode(LCD_RD,OUTPUT);
pinMode(LCD_WR,OUTPUT);
pinMode(LCD_RS,OUTPUT);
pinMode(LCD_CS,OUTPUT);
pinMode(LCD_RST,OUTPUT);
digitalWrite(LCD_CS,LOW);
digitalWrite(LCD_RD,HIGH);
digitalWrite(LCD_WR,LOW);
//Reset
digitalWrite(LCD_RST,HIGH);
delay(5);
digitalWrite(LCD_RST,LOW);
delay(15);
digitalWrite(LCD_RST,HIGH);
delay(15);
LcdWriteCommand(0xCB);
LcdWriteData(0x39);
LcdWriteData(0x2C);
LcdWriteData(0x00);
LcdWriteData(0x34);
LcdWriteData(0x02);
LcdWriteCommand(0xCF);
LcdWriteData(0x00);
LcdWriteData(0XC1);
LcdWriteData(0X30);
LcdWriteCommand(0xE8);
LcdWriteData(0x85);
LcdWriteData(0x00);
LcdWriteData(0x78);
LcdWriteCommand(0xEA);
LcdWriteData(0x00);
LcdWriteData(0x00);
LcdWriteCommand(0xED);
LcdWriteData(0x64);
LcdWriteData(0x03);
LcdWriteData(0X12);
LcdWriteData(0X81);
LcdWriteCommand(0xF7);
LcdWriteData(0x20);
LcdWriteCommand(0xC0); //Power control
LcdWriteData(0x23); //VRH[5:0]
LcdWriteCommand(0xC1); //Power control
LcdWriteData(0x10); //SAP[2:0];BT[3:0]
LcdWriteCommand(0xC5); //VCM control
LcdWriteData(0x3e); //Contrast
LcdWriteData(0x28);
LcdWriteCommand(0xC7); //VCM control2
LcdWriteData(0x86); //--
LcdWriteCommand(0x36); // Memory Access Control
LcdWriteData(0x48);
LcdWriteCommand(0x3A);
LcdWriteData(0x55);
LcdWriteCommand(0xB1);
LcdWriteData(0x00);
LcdWriteData(0x18);
LcdWriteCommand(0xB6); // Display Function Control
LcdWriteData(0x08);
LcdWriteData(0x82);
LcdWriteData(0x27);
LcdWriteCommand(0x11); //Exit Sleep
delay(120);
LcdWriteCommand(0x29); //Display on
LcdWriteCommand(0x2c);
}
void LcdOpenWindow(unsigned int x1,unsigned int y1,unsigned int x2,unsigned int y2){
LcdWriteCommand(0x2a);
LcdWriteData(x1>>8);
LcdWriteData(x1);
LcdWriteData(x2>>8);
LcdWriteData(x2);
LcdWriteCommand(0x2b);
LcdWriteData(y1>>8);
LcdWriteData(y1);
LcdWriteData(y2>>8);
LcdWriteData(y2);
LcdWriteCommand(0x2c);
}
void LcdFill(int x,int y,int width,int height,unsigned int color)
{
LcdOpenWindow(x,y,x+width-1,y+height-1);
for(int i=y;i<y+height;i++){
for(int j=x;j<x+width;j++){
LcdWriteData(color>>8);
LcdWriteData(color);
}
}
}
void setup(){
LcdInit();
LcdFill(0,0,239,319,RGB(31,63,31));
LcdFill(10,10,100,100,RGB(31,0,0));
LcdFill(20,20,110,110,RGB(0,63,0));
LcdFill(30,30,120,120,RGB(0,0,31));
}
void loop(){
}
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标签：Pin,Arduino,digitalWrite,LcdWriteCommand,LcdWriteData,LCD,全过程,ILI9341,define 来源： https://www.cnblogs.com/lyj00912/p/12180140.html