Arduino网络编程实战-OLED显示天气信息

OLED显示天气信息

Arduino Ethernet Shield V1 允许 Arduino 板连接到互联网。它基于 Wiznet W5100ethernet 芯片（数据表）。 Wiznet W5100 提供支持 TCP 和 UDP 的网络 (IP) 堆栈。它最多支持四个同时套接字连接。

本实例将演示获取天气JSON数据、数据解析、并在OLED中显示天气。

通过使用OLED显示天气信息主要由以下步骤组成：

1）请求天气信息，请参考：

2）解析天气JSON信息，请参考：

3）根据天气代码显示天气图片、城市名称、温度信息，请参考：

1、硬件准备

Arduino Mega2560 开发板一块
SD卡模块一个及SD卡一个
SSD1306 OLED屏幕一块
数据线一条
杜邦线若干

硬件接线，请关于前面相关文章，在这里不再做描述。

2、软件准备

Arduino IDE
SSD1306 OLED驱动库：Adafruit_SSD1306
图形支持库：Adafruit-GFX-Library
JSON支持库：ArduinoJson
SD卡驱动库：SdFat
Pctolcd2002(请自行网络搜索下载)

3、代码实现

3.1 导入相关头文件

#include <SPI.h>
#include <Wire.h>
#include <Adafruit\_GFX.h>
#include <Adafruit\_SSD1306.h>
#include <SdFat.h>
#include <ArduinoJson.h>
#include <Ethernet.h>


#define SCREEN\_WIDTH 128 // OLED display width, in pixels
#define SCREEN\_HEIGHT 64 // OLED display height, in pixels

#define OLED\_RESET -1 // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN\_ADDRESS 0x3C ///< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// SD\_FAT\_TYPE = 0 for SdFat/File as defined in SdFatConfig.h,
// 1 for FAT16/FAT32, 2 for exFAT, 3 for FAT16/FAT32 and exFAT.
// SD卡文件系统格式类型
#define SD\_FAT\_TYPE 0
#define SD\_CS\_PIN 4
#define SPI\_CLOCK SD\_SCK\_MHZ(50)
#define SD\_CONFIG SdSpiConfig(SD\_CS\_PIN, DEDICATED\_SPI, SPI\_QUARTER\_SPEED)
#if SD\_FAT\_TYPE == 0
  SdFat sd;
  File file;
#elif SD\_FAT\_TYPE == 1
  SdFat32 sd;
  File32 file;
#elif SD\_FAT\_TYPE == 2
  SdExFat sd;
  ExFile file;
#elif SD\_FAT\_TYPE == 3
  SdFs sd;
  FsFile file;
#else // SD\_FAT\_TYPE
  #error Invalid SD\_FAT\_TYPE
#endif // SD\_FAT\_TYPE

#define USE\_STATIC 1

byte mac[] = {
  0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED
};
#if USE\_STATIC
IPAddress ip(192, 168, 0, 116);
#endif

unsigned char img_datas [1024] = {0};
const String beijing_fonts[] = {"fonts/cn\_bei.json","fonts/cn\_jing.json"};
const String weather_code_0 = "weather\_image\_configs/files/0@2x.json";
const String weather_temp_icon = "weather\_image\_configs/files/170@1x.json";
DeserializationError error;
int width,height,len;

3.2 OLED初始化


// 串口初始化
  Serial.begin(9600);
  // OLED初始化
  if(!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Don't proceed, loop forever
  }

  // 显示欢迎屏幕
  display.display();
  // 清屏
  display.clearDisplay();

  // 设置字体
  display.setTextSize(1);      // Normal 1:1 pixel scale
  display.setTextColor(SSD1306_WHITE); // Draw white text
  display.setCursor(0, 0);     // Start at top-left corner
  display.cp437(true);         // Use full 256 char 'Code Page 437' font

3.3 网卡初始化

  // 初始化网卡
  selectEthernet();
#if USE\_STATIC
   Ethernet.begin(mac,ip);
#else
  Ethernet.begin(mac);
#endif

   if (Ethernet.hardwareStatus() == EthernetNoHardware) {
    Serial.println("Ethernet shield was not found. Sorry, can't run without hardware. :(");
    display.setCursor(0,0);
    display.println("Ethernet Failed");
    display.display();
    while (true) {
      delay(1); 
    }
  }
  if (Ethernet.linkStatus() == LinkOFF) {
    Serial.println("Ethernet cable is not connected.");
    display.clearDisplay();
    display.setCursor(0,0);
    display.println("Ethernet LinkOFF");
    display.display();
    while(true){
      delay(1);  
    }
  }
  
  Serial.print("IP:");
  Serial.println(Ethernet.localIP());
  Serial.print("Subnet Mask:");
  Serial.println(Ethernet.subnetMask());
  Serial.print("Gateway:");
  Serial.println(Ethernet.gatewayIP());
  Serial.print("DNS Server:");
  Serial.println(Ethernet.dnsServerIP());
  
  display.clearDisplay();
  display.setCursor(0,0);
  display.print("IP:");
  display.print(Ethernet.localIP());
  display.display();

3.4 SD卡初始化

// SD卡初始化
  selectSdcard();
  // Initialize the SD.
  if (!sd.begin(SD_CONFIG)) {
    display.clearDisplay();
    display.setCursor(0,16);
    display.print("SDCard failed");
    display.display();
    sd.initErrorHalt(&Serial);
    return;
  }
  
  //display.clearDisplay();
  display.setCursor(0,16);
  display.print("SDCard Inited");
  display.display();
  Serial.println("Initialized SD card...");

3.5 请求天气信息

selectEthernet();
 // Connect to HTTP server
 EthernetClient client;
 client.setTimeout(10000);
 Serial.println("Connecting....");
 if (!client.connect("api.seniverse.com", 80)) {
   Serial.println("Connection failed");
   return;
 }

 Serial.println(F("Connected!"));
 // Send HTTP request
 client.println(F("GET /v3/weather/now.json?key=【你的API Key】&location=beijing&language=zh-Hans&unit=c HTTP/1.0"));
 client.println(F("Host: api.seniverse.com"));
 client.println("Content-Type: application/json");
 client.println("Connection: close"); // or close
 client.println("User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.82 Safari/537.36");
   //client.print("Content-Length: ");
 client.println("Connection: close");
 client.println(F("Connection: close"));
 if (client.println() == 0) {
   Serial.println(F("Failed to send request"));
   client.stop();
   return;
 }

 // Check HTTP status
 char status[32] = {0};
 client.readBytesUntil('\r', status, sizeof(status));
 if (strcmp(status, "HTTP/1.1 200 OK") != 0) {
   Serial.print(F("Unexpected response: "));
   Serial.println(status);
   client.stop();
   return;
 }

 // Skip HTTP headers
 char endOfHeaders[] = "\r\n\r\n";
 if (!client.find(endOfHeaders)) {
   Serial.println(F("Invalid response"));
   client.stop();
   return;
 }

 // Allocate the JSON document
 // Use arduinojson.org/v6/assistant to compute the capacity.
 //const size\_t capacity = 1024;//JSON\_OBJECT\_SIZE(3) + JSON\_ARRAY\_SIZE(2) + 60;
 DynamicJsonDocument doc(2048);

 // Parse JSON object
 error = deserializeJson(doc, client);
 if (error) {
   Serial.print(F("deserializeJson() failed: "));
   Serial.println(error.f\_str());
   client.stop();
   return;
 }
 // Disconnect
 client.stop();

3.6 解析天气信息

// 解析天气信息
 serializeJson(doc, Serial);
 Serial.println();
 // Extract values
 String id = doc["results"][0]["location"]["id"].as<String>();
 String temp = doc["results"][0]["now"]["temperature"].as<String>();
 String code = doc["results"][0]["now"]["code"].as<String>();
 Serial.println(id);
 Serial.println(temp);
 Serial.println(code);
 
 display.setCursor(0,0);
 display.setTextSize(1); //设置字体大小
 display.setTextColor(SSD1306_WHITE);//开像素点发光

3.7 显示天气城市名

display.clearDisplay();
 display.display();
 selectSdcard();

 // 解析并显示城市名称
 if(id == "WX4FBXXFKE4F"){
   
   for(int j = 0;j < 2;j++){
    
     Serial.println(beijing_fonts[j].c\_str());
     if (!file.open(beijing_fonts[j].c\_str(), O_RDWR)) {
       Serial.println("open failed");
         while(true);
     }
     error = deserializeJson(doc, file);
    
     int width = doc["width"].as<int>();
     int height = doc["height"].as<int>();
     int len;
     //serializeJson(doc, Serial);
     memset(img_datas,0,1024);
     Serial.print("data len:");
     Serial.println(doc["datas"].as<JsonArray>().size());
     len = doc["datas"].as<JsonArray>().size();
     if(len > 0){
       for(int i = 0;i < len;i++){
           img_datas[i] = doc["datas"][i].as<unsigned char>();
       }
       display.drawBitmap(j \* 16, 0, img_datas, 16, 16, 1);
     }
     file.close();
     // 绘制字符
    
   }
 }

3.8 显示天气温度

// 解析并显示温度值及图标
  display.setTextSize(4);      // Normal 1:1 pixel scale
  display.setTextColor(SSD1306_WHITE); // Draw white text
  display.setCursor(32, 24);     // Start at top-left corner
  display.cp437(true);         // Use full 256 char 'Code Page 437' font

  display.print(temp.c\_str());
  doc.clear();
  Serial.println(weather_temp_icon.c\_str());
  if (!file.open(weather_temp_icon.c\_str(), O_RDWR)) {
    Serial.println("open failed");
    while(true);
  }
  error = deserializeJson(doc, file);
  width = doc["width"].as<int>();
  height = doc["height"].as<int>();
  memset(img_datas,0,1024);
  Serial.print("data len:");
  Serial.println(doc["datas"].as<JsonArray>().size());
  len = doc["datas"].as<JsonArray>().size();
  if(len > 0){
    for(int i = 0;i < len;i++){
      img_datas[i] = doc["datas"][i].as<unsigned char>();
    }
    file.close();
    display.drawBitmap(64, 24, img_datas, 32, 32, 1);
  }

3.9 显示天气代码图标

// 解析并显示天气图标
  if(code == "0"){
    doc.clear();
    Serial.println(weather_code_0.c\_str());
    if (!file.open(weather_code_0.c\_str(), O_RDWR)) {
      Serial.println("open failed");
        while(true);
    }
    error = deserializeJson(doc, file);
    width = doc["width"].as<int>();
    height = doc["height"].as<int>();
    //serializeJson(doc, Serial);
    memset(img_datas,0,1024);
    Serial.print("data len:");
    Serial.println(doc["datas"].as<JsonArray>().size());
    len = doc["datas"].as<JsonArray>().size();
    if(len > 0){
    for(int i = 0;i < len;i++){
      img_datas[i] = doc["datas"][i].as<unsigned char>();
    }
    file.close();
      
     display.drawBitmap(112, 0, img_datas, 16, 16, 1);
     display.display();
    }
 }

4、运行结果

文章来源: https://iotsmart.blog.csdn.net/article/details/123050211