esp笔记（8）驱动全彩 OLED（SSD1351）的显示
本文开发环境：
- MCU型号：ESP8266
- IDE环境 ： Arduino IDE 1.8.9
- 1.27寸 全彩 OELD模块
本文内容：
- esp8266 使用 u8g2图形库 驱动 OELD 显示
- 自定义软件SPI接口
文章目录
- 一、简介
- 二、程序
-
- 2.1 IO口定义
- 2.2 模拟SPI写时序
- 2.3 驱动 OLED 模块
- 2.4 字符数组
- 三、源码与示例
-
- 3.1 完整源码
- 示例
一、简介
使用ESP8266模块（LoLin）驱动1.27寸全彩OLED：
本文使用功的OLED为SSD1351驱动的全彩OLED，由于u8g2库没有支持SSD1351控制器，所以我们通过自己写驱动函数，来点亮一个SSD1351 驱动 OLED。本文代码来自网络。详见：ORIGINAL TUTORIAL
二、程序
2.1 IO口定义
本文使用的是模拟的 SPI 接口，首先有如下定义：
#define sclk 14 //WEMOS D5 pin
#define mosi 13 //WEMOS D7
#define cs 15 //WEMOS D8
const int DCpin = 4; //WEMOS D2
const int RSTpin = 5; //WEMOS D1
这种定义的方法非常常见甚至必要，它可以让阅读代码的人一目了然，比如：
#define sclk 14 //WEMOS D5 pin
这段代码可以获取到的信息：模块的SCLK（SPI时钟线）接ESP8266的GPIO14脚，也就是WEMOS模块的丝印 D5 的IO口。同时，如果我们需要修改SCLK，也装修要修改该宏定义即可。
2.2 模拟SPI写时序
当我们定义好IO口以后，需要来模拟SPI的写时序：
void SPIwrite(uint8_t c){
digitalWrite(sclk, HIGH);
int8_t i; //signed intでなければならない。負の数になると255という値になって、例外エラーになる。
for (i=7; i>=0; i--) {
digitalWrite(sclk, LOW);
if (c & _BV(i)) {
digitalWrite(mosi, HIGH);
} else {
digitalWrite(mosi, LOW);
}
digitalWrite(sclk, HIGH);
}
}
可以看到，我们发送了8个字节，所以模拟的是一次发送8个字节的SPI时序，注意到SPI协议不要求一次性只能发送8个，不过8个字节应该是最常见的。有了SPI 的时序，还可以进一步封装，将 SPI 写命令和写字节的函数封装：
void writeCommand(uint8_t c) {
digitalWrite(DCpin, LOW);
digitalWrite(cs, LOW);
SPIwrite(c);
digitalWrite(cs, HIGH);
}
void writeData(uint8_t c) {
digitalWrite(DCpin, HIGH);
digitalWrite(cs, LOW);
SPIwrite(c);
digitalWrite(cs, HIGH);
}
对于模块而已，DC脚的高低电平用来判断主机发送的字节是指令（cmd）还是数据（data），所以程序只需要拉低或拉高DC脚，然后调用SPIwrite()，写入字节即可。
2.3 驱动 OLED 模块
当写好写命令和指令的函数以后，就可以驱动OELD了，通常我们会参考官方的demo 或 数据手册，来完成一系列的写操作：
//****************SSD1351初期化*************************************************
void SSD1351_Init() {
writeCommand(0xFD);
//Set Command Lock
writeData(0x12);
//Unlock OLED driver IC MCU interface from entering command
writeCommand(0xFD);
//Set Command Lock
writeData(0xB1);
//Command A2,B1,B3,BB,BE,C1 accessible if in unlock state
writeCommand(0xAE);
//Sleep mode On (Display OFF)
writeCommand(0xB3);
//Front Clock Divider
writeCommand(0xF1);
// 7:4 = Oscillator Frequency, 3:0 = CLK Div Ratio (A[3:0]+1 = 1..16)
writeCommand(0xCA);
//Set MUX Ratio
writeData(127);
writeCommand(0xA0);
//Set Re-map
writeData(B01110100);
//65k color
//writeData(B10110100); //262k color
//writeData(B11110100); //262k color, 16-bit format 2
writeCommand(0x15);
//Set Column
writeData(0);
//start
writeData(127);
//end
writeCommand(0x75);
//Set Row
writeData(0);
//start
writeData(127);
//end
writeCommand(0xA1);
//Set Display Start Line
writeData(0);
writeCommand(0xA2);
//Set Display Offset
writeData(0);
writeCommand(0xB5);
//Set GPIO
writeData(0);
writeCommand(0xAB);
//Function Selection
writeData(0x01);
//Enable internal Vdd /8-bit parallel
//writeData(B01000001); //Enable internal Vdd /Select 16-bit parallel interface
writeCommand(0xB1);
//Set Reset(Phase 1) /Pre-charge(Phase 2)
//writeCommand(B00110010); //5 DCLKs / 3 DCLKs
writeCommand(0x74);
writeCommand(0xBE);
//Set VCOMH Voltage
writeCommand(0x05);
//0.82 x VCC [reset]
writeCommand(0xA6);
//Reset to normal display
writeCommand(0xC1);
//Set Contrast
writeData(0xC8);
//Red contrast (reset=0x8A)
writeData(0x80);
//Green contrast (reset=0x51)
writeData(0xC8);
//Blue contrast (reset=0x8A)
writeCommand(0xC7);
//Master Contrast Current Control
writeData(0x0F);
//0-15
writeCommand(0xB4);
//Set Segment Low Voltage(VSL)
writeData(0xA0);
writeData(0xB5);
writeData(0x55);
writeCommand(0xB6);
//Set Second Precharge Period
writeData(0x01);
//1 DCLKS
writeCommand(0x9E);
//Scroll Stop Moving
writeCommand(0xAF);
//Sleep mode On (Display ON)
}
可以看到，我们通过写指令和数据来对OLED进行设置，如解锁，时钟频率，颜色模式等等。如果你想进一步了解：参考资料
2.4 字符数组
在驱动OELD以后，就可以通过写指令指定OELD在屏幕的某一个坐标绘制一个带颜色的点，一个字符通常就是这些坐标的集合，所以我们可以通过数组的形式，来表示字符：
uint8_t bicho [16] ={0x0,0x0,0x66,0x7E,0x3C,0x18,0xFF,0x99,0x3C,0xFF,0xBD,0xBD,0x99,0x81,0x0,0x0};
uint8_t empty [16] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};//erases one character
uint8_t zero [16] = {0xff,0xff,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff};//goes like a scanner
uint8_t one [16] = {0x18,0x18,0x18,0xf8,0xf8,0x18,0x18,0x18,0x18,0x18,0x18,0x18,0x18,0x18,0xff,0xff};//goes like a scanner
uint8_t two [16] = {0xff,0xff,0xc3,0xc3,0x03,0x03,0x03,0xff,0xff,0xc0,0xc0,0xc0,0xc3,0xc3,0xff,0xff};//goes like a scanner
uint8_t three[16] = {0xff,0xff,0x03,0x03,0x03,0x03,0x03,0xff,0xff,0x03,0x03,0x03,0x03,0x03,0xff,0xff};//goes like a scanner
uint8_t four [16] = {0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff,0x03,0x03,0x03,0x03,0x03,0x03,0x03};//goes like a scanner
uint8_t five [16] = {0xff,0xff,0xc3,0xc3,0xc0,0xc0,0xc0,0xff,0xff,0x03,0x03,0x03,0xc3,0xc3,0xff,0xff};//goes like a scanner
uint8_t six [16] = {0xff,0xff,0xc3,0xc3,0xc0,0xc0,0xc0,0xff,0xff,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff};//goes like a scanner
uint8_t seven[16] = {0xff,0xff,0xc3,0xc3,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03};//goes like a scanner
uint8_t eight[16] = {0xff,0xff,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff};//goes like a scanner
uint8_t nine [16] = {0xff,0xff,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff,0x03,0x03,0x03,0x03,0x03,0x03,0x03};//goes like a scanner
当OLED按照这些数据绘制像素点时，就会显示对应的字符了。我们需要一个绘制函数：
//****************等倍フォント表示*************************************************
void Font1x1(uint8_t StartX, uint8_t StartY, uint8_t Red, uint8_t Green, uint8_t Blue, uint8_t* buf) {
int16_t i,j;
uint8_t RGBbit1, RGBbit2;
RGBbit1 = (Red<<3) | (Green>>3);
RGBbit2 = (Green<<5) | Blue;
writeCommand(0x15);
//Set Column
writeData(StartX);
writeData(StartX+7);
writeCommand(0x75);
//Set Row
writeData(StartY);
writeData(StartY+15);
writeCommand(0x5C);
//Write RAM
for (i=0; i<16; i++) {
for (j=7; j>=0; j--) {
if(buf[i] & _BV(j)) {
writeData(RGBbit1);
writeData(RGBbit2);
} else {
writeData(0);
writeData(0);
}
}
}
yield(); //避免软件看门狗复位
}
这个函数通过接收颜色数据，以及字符数据，来显示相应的内容。注意到，此处yield()，是博主添加的函数，为了避免软件看门狗复位，源程序无该语句，可能是程序完成时，编译器并没有软件开门狗。
三、源码与示例
3.1 完整源码
以下是完整的源码：
* It does not work with Arduino UNO.
* Scavenged by Javier Muñoz [email protected], 22/12/2016
* ORIGINAL TUTORIAL FROM:(japanese) https://translate.google.com/translate?hl=en&sl=/auto&tl=en&u=https%3A%2F%2Fwww.mgo-tec.com%2Fblog-entry-adafruit-oled-ssd1351-esp-wroom-nonlib.html&sandbox=1
*/
//we dont need to include SPI.h to use it, arduino christmas magic
#define sclk 14 //WEMOS D5 pin
#define mosi 13 //WEMOS D7
#define cs 15 //WEMOS D8
const int DCpin = 4;
//WEMOS D2
const int RSTpin = 5;
//WEMOS D1
uint8_t bicho [16] = {
0x0,0x0,0x66,0x7E,0x3C,0x18,0xFF,0x99,0x3C,0xFF,0xBD,0xBD,0x99,0x81,0x0,0x0
}
;
uint8_t empty [16] = {
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
}
;
//erases one character
uint8_t zero [16] = {
0xff,0xff,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff
}
;
//goes like a scanner
uint8_t one [16] = {
0x18,0x18,0x18,0xf8,0xf8,0x18,0x18,0x18,0x18,0x18,0x18,0x18,0x18,0x18,0xff,0xff
}
;
//goes like a scanner
uint8_t two [16] = {
0xff,0xff,0xc3,0xc3,0x03,0x03,0x03,0xff,0xff,0xc0,0xc0,0xc0,0xc3,0xc3,0xff,0xff
}
;
//goes like a scanner
uint8_t three[16] = {
0xff,0xff,0x03,0x03,0x03,0x03,0x03,0xff,0xff,0x03,0x03,0x03,0x03,0x03,0xff,0xff
}
;
//goes like a scanner
uint8_t four [16] = {
0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff,0x03,0x03,0x03,0x03,0x03,0x03,0x03
}
;
//goes like a scanner
uint8_t five [16] = {
0xff,0xff,0xc3,0xc3,0xc0,0xc0,0xc0,0xff,0xff,0x03,0x03,0x03,0xc3,0xc3,0xff,0xff
}
;
//goes like a scanner
uint8_t six [16] = {
0xff,0xff,0xc3,0xc3,0xc0,0xc0,0xc0,0xff,0xff,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff
}
;
//goes like a scanner
uint8_t seven[16] = {
0xff,0xff,0xc3,0xc3,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03
}
;
//goes like a scanner
uint8_t eight[16] = {
0xff,0xff,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff
}
;
//goes like a scanner
uint8_t nine [16] = {
0xff,0xff,0xc3,0xc3,0xc3,0xc3,0xc3,0xff,0xff,0x03,0x03,0x03,0x03,0x03,0x03,0x03
}
;
//goes like a scanner
//String numeros[10] = { "one", "two", "three","four","five","six","seven","eight","nine" };
uint8_t *pointernumeros[10];
//****************セットアップ*************************************************
void setup() {
Serial.begin(9600);
pointernumeros[0]=zero;
pointernumeros[1]=one;
pointernumeros[2]=two;
pointernumeros[3]=three;
pointernumeros[4]=four;
pointernumeros[5]=five;
pointernumeros[6]=six;
pointernumeros[7]=seven;
pointernumeros[8]=eight;
pointernumeros[9]=nine;
pinMode(DCpin, OUTPUT);
pinMode(sclk, OUTPUT);
pinMode(mosi, OUTPUT);
pinMode(RSTpin, OUTPUT);
pinMode(cs, OUTPUT);
digitalWrite(cs, LOW);
digitalWrite(RSTpin, HIGH);
delay(500);
digitalWrite(RSTpin, LOW);
delay(500);
digitalWrite(RSTpin, HIGH);
delay(500);
SSD1351_Init();
delay(100);
SSD1351_BlackOut();
uint8_t Red = 31, Green = 63, Blue = 31;
//Max Red = 31, Max Green = 63, MaxBlue = 31
int i=0;
Font1x1(i, 48, Red, 0, 0, zero);
i=i+10;
Font1x1(i, 48, Red, 0, 0, one);
i=i+10;
Font1x1(i, 48, Red, 0, 0, two);
i=i+10;
Font1x1(i, 48, Red, 0, 0, three);
i=i+10;
Font1x1(i, 48, Red, 0, 0, four);
i=i+10;
Font1x1(i, 48, Red, 0, 0, five);
i=i+10;
Font1x1(i, 48, Red, 0, 0, six);
i=i+10;
Font1x1(i, 48, Red, 0, 0, seven);
i=i+10;
Font1x1(i, 48, Red, 0, 0, eight);
i=i+10;
Font1x1(i, 48, Red, 0, 0, nine);
// Font1x1(8, 0, Red, Green, Blue, font_a[1]);
// Font2x2(0, 16, Red, Green, Blue, font_a[0]);
// Font2x2(16, 16, Red, Green, Blue, font_a[1]);
//
// Green = 0; Blue = 0;
// Font1x1(32, 32, Red, Green, Blue, font_a[0]);
// Font1x1(40, 32, Red, Green, Blue, font_a[1]);
//
// Red = 0; Green = 63; Blue = 0;
// Font2x2(48, 48, Red, Green, Blue, font_a[0]);
// Font2x2(64, 48, Red, Green, Blue, font_a[1]);
//
// Red = 0; Green = 0; Blue = 31;
// Font1x1(80, 80, Red, Green, Blue, font_a[0]);
// Font1x1(88, 80, Red, Green, Blue, font_a[1]);
//
// Red = 31; Green = 63; Blue = 20;
// Font2x2(96, 96, Red, Green, Blue, font_a[0]);
// Font2x2(112, 96, Red, Green, Blue, font_a[1]);
SSD1351_BlackOut();
}
//****************メインループ*************************************************
void loop() {
int i=random(0, 100);
int j=random(0, 100);
WriteNumber99(i,i,j,i-j,i*8,j);
// Font2x2(i, j, j, i-j, i*8, bicho);//bug rain
//THIS THING COUNTS 0-1000
// SSD1351_BlackOut();
// for(int y=0;y<10;y++){
// Font1x1(18, 48, 30, 63, 31, empty);
// Font1x1(18, 48, y*5, 63-y*5,0, pointernumeros[y]);
//
// for(int j=0;j<10;j++){
// Font1x1(30, 48, 30, 63, 0, empty);
// Font1x1(30, 48, y*5, 63-y*5, 0, pointernumeros[j]);
// delay(20);
// for(int i=0;i<10;i++){
// Font1x1(42, 48, 30, 63, 0, empty);
// Font1x1(42, 48, y*5, 63-y*5, 0, pointernumeros[i]);
//delay(20);
// }
// }
// }
}
//****************SSD1351初期化*************************************************
void SSD1351_Init() {
writeCommand(0xFD);
//Set Command Lock
writeData(0x12);
//Unlock OLED driver IC MCU interface from entering command
writeCommand(0xFD);
//Set Command Lock
writeData(0xB1);
//Command A2,B1,B3,BB,BE,C1 accessible if in unlock state
writeCommand(0xAE);
//Sleep mode On (Display OFF)
writeCommand(0xB3);
//Front Clock Divider
writeCommand(0xF1);
// 7:4 = Oscillator Frequency, 3:0 = CLK Div Ratio (A[3:0]+1 = 1..16)
writeCommand(0xCA);
//Set MUX Ratio
writeData(127);
writeCommand(0xA0);
//Set Re-map
writeData(B01110100);
//65k color
//writeData(B10110100); //262k color
//writeData(B11110100); //262k color, 16-bit format 2
writeCommand(0x15);
//Set Column
writeData(0);
//start
writeData(127);
//end
writeCommand(0x75);
//Set Row
writeData(0);
//start
writeData(127);
//end
writeCommand(0xA1);
//Set Display Start Line
writeData(0);
writeCommand(0xA2);
//Set Display Offset
writeData(0);
writeCommand(0xB5);
//Set GPIO
writeData(0);
writeCommand(0xAB);
//Function Selection
writeData(0x01);
//Enable internal Vdd /8-bit parallel
//writeData(B01000001); //Enable internal Vdd /Select 16-bit parallel interface
writeCommand(0xB1);
//Set Reset(Phase 1) /Pre-charge(Phase 2)
//writeCommand(B00110010); //5 DCLKs / 3 DCLKs
writeCommand(0x74);
writeCommand(0xBE);
//Set VCOMH Voltage
writeCommand(0x05);
//0.82 x VCC [reset]
writeCommand(0xA6);
//Reset to normal display
writeCommand(0xC1);
//Set Contrast
writeData(0xC8);
//Red contrast (reset=0x8A)
writeData(0x80);
//Green contrast (reset=0x51)
writeData(0xC8);
//Blue contrast (reset=0x8A)
writeCommand(0xC7);
//Master Contrast Current Control
writeData(0x0F);
//0-15
writeCommand(0xB4);
//Set Segment Low Voltage(VSL)
writeData(0xA0);
writeData(0xB5);
writeData(0x55);
writeCommand(0xB6);
//Set Second Precharge Period
writeData(0x01);
//1 DCLKS
writeCommand(0x9E);
//Scroll Stop Moving
writeCommand(0xAF);
//Sleep mode On (Display ON)
}
//****************全画面消去*************************************************
void SSD1351_BlackOut() {
writeCommand(0x15);
//Set Column
writeData(0x00);
writeData(127);
writeCommand(0x75);
//Set Row
writeData(0x00);
writeData(127);
writeCommand(0x5C);
//Write RAM
for (int i=0; i<128*128; i++) {
writeData(0x00);
writeData(0x00);
//writeData(0x00); //262k colorの場合３バイト分送信
}
}
//****************等倍フォント表示*************************************************
void Font1x1(uint8_t StartX, uint8_t StartY, uint8_t Red, uint8_t Green, uint8_t Blue, uint8_t* buf) {
int16_t i,j;
uint8_t RGBbit1, RGBbit2;
RGBbit1 = (Red<<3) | (Green>>3);
RGBbit2 = (Green<<5) | Blue;
writeCommand(0x15);
//Set Column
writeData(StartX);
writeData(StartX+7);
writeCommand(0x75);
//Set Row
writeData(StartY);
writeData(StartY+15);
writeCommand(0x5C);
//Write RAM
for (i=0; i<16; i++) {
for (j=7; j>=0; j--) {
if(buf[i] & _BV(j)) {
writeData(RGBbit1);
writeData(RGBbit2);
} else {
writeData(0);
writeData(0);
}
}
}
yield();
}
//****************倍角フォント表示*************************************************
void Font2x2(uint8_t StartX, uint8_t StartY, uint8_t Red, uint8_t Green, uint8_t Blue, uint8_t* buf) {
int16_t i,j,ii;
uint8_t RGBbit1, RGBbit2;
RGBbit1 = (Red<<3) | (Green>>3);
RGBbit2 = (Green<<5) | Blue;
writeCommand(0x15);
//Set Column
writeData(StartX);
writeData(StartX+15);
writeCommand(0x75);
//Set Row
writeData(StartY);
writeData(StartY+31);
writeCommand(0x5C);
//Write RAM
for (i=0; i<16; i++) {
for (ii=0; ii<2; ii++) {
//倍角の場合２行同じものを描く
for (j=7; j>=0; j--) {
if(buf[i] & _BV(j)) {
writeData(RGBbit1);
writeData(RGBbit2);
writeData(RGBbit1);
writeData(RGBbit2);
} else {
writeData(0);
writeData(0);
writeData(0);
writeData(0);
}
}
}
yield();
}
}
//****************SPIデータ処理*************************************************
void SPIwrite(uint8_t c) {
digitalWrite(sclk, HIGH);
int8_t i;
//signed intでなければならない。負の数になると255という値になって、例外エラーになる。
for (i=7; i>=0; i--) {
digitalWrite(sclk, LOW);
if (c & _BV(i)) {
digitalWrite(mosi, HIGH);
} else {
digitalWrite(mosi, LOW);
}
digitalWrite(sclk, HIGH);
}
}
void writeCommand(uint8_t c) {
digitalWrite(DCpin, LOW);
digitalWrite(cs, LOW);
SPIwrite(c);
digitalWrite(cs, HIGH);
}
void writeData(uint8_t c) {
digitalWrite(DCpin, HIGH);
digitalWrite(cs, LOW);
SPIwrite(c);
digitalWrite(cs, HIGH);
}
Write number 00 Up to to 99
void WriteNumber99(int number,int x,int y,int red,int green, int blue) {
int unit=0;
int dec=0;
dec=number/10;
unit=number-(dec*10);
Serial.print(dec);
Serial.print(" ");
Serial.println(unit);
Font1x1(x, y+32,red, green,blue, pointernumeros[dec]);
Font1x1(x+12, y+32,red, green,blue, pointernumeros[unit]);
}
Write number 00 Up to to 999
void WriteNumber999(int number,int x,int y,int red,int green, int blue) {
int unit=0;
int dec=0;
int cent=0;
cent=number/100;
dec=(number-(cent*100))/10;
unit=number-(dec*10)-(cent*100);
Serial.print( cent);
Serial.print( " ");
Serial.print( dec);
Serial.print( " ");
Serial.println( unit);
Font1x1(x, y+32,red, green,blue, pointernumeros[cent]);
//y has a offset of 32 because the code is for 128pixel screen
Font1x1(x+12, y+32,red, green,blue, pointernumeros[dec]);
Font1x1(x+24, y+32,red, green,blue, pointernumeros[unit]);
}
示例
本文源码的使用是简单的，首先将完整的源码编译下载，然后连线即可：
| OLED | ESP8266 | LoLin（WEMOS） |
|---|---|---|
| sclk | 14 | D5 |
| mosi | 13 | D7 |
| cs | 15 | D8 |
| DCpin | 4 | D2 |
| RSTpin | 5 | D1 |