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Wio Terminal 显示疫情实时数据
Demo 概述
这个 Demo 是由 Wio Terminal 抓取 GitHub 数据 修改过来的，展示了如何使用 Wio Terminal 从网络获取 COVID-19 的实时数据，并显示到 LCD 屏幕上。
重点难点
- 连接 HTTPS 服务器
- 获取 COVID-19 实时数据 API
- 实现按键手动刷新数据
安装依赖库
本示例 Demo 依赖 LCD 库、ArduinoJson 库和 Free_Fonts.h 字体库：
LCD库在安装 Seeed SAMD Boards 库时已经包含了，大家可以参考 Wio Terminal 开发环境。ArduinoJson库可以在 GitHub 仓库下载，在 Arduino IDE 点击 项目 > 加载库 > 添加 .ZIP 库… 即可添加库。Free_Fonts.h库提供了一些免费字体，可以点击这里下载，并将它放在 Arduino 工程中。
关于 HTTP 和 HTTPS 连接，请参考 Wio Terminal HTTP 连接。
完整代码
提示：将下面代码中的 ssid 和 password 替换成你的 WiFi 网络。
#include "rpcWiFi.h"
#include <WiFiClientSecure.h>
#include <ArduinoJson.h>
#include"Free_Fonts.h"
#include"TFT_eSPI.h"
TFT_eSPI tft;
const char* ssid = "YourNetworkName";
const char* password = "yourNetworkPassword";
const char* server = "api.covid19api.com"; // Server URL
const char* test_root_ca = \
"-----BEGIN CERTIFICATE-----\n"
"MIIEkjCCA3qgAwIBAgIQCgFBQgAAAVOFc2oLheynCDANBgkqhkiG9w0BAQsFADA/\n"
"MSQwIgYDVQQKExtEaWdpdGFsIFNpZ25hdHVyZSBUcnVzdCBDby4xFzAVBgNVBAMT\n"
"DkRTVCBSb290IENBIFgzMB4XDTE2MDMxNzE2NDA0NloXDTIxMDMxNzE2NDA0Nlow\n"
"SjELMAkGA1UEBhMCVVMxFjAUBgNVBAoTDUxldCdzIEVuY3J5cHQxIzAhBgNVBAMT\n"
"GkxldCdzIEVuY3J5cHQgQXV0aG9yaXR5IFgzMIIBIjANBgkqhkiG9w0BAQEFAAOC\n"
"AQ8AMIIBCgKCAQEAnNMM8FrlLke3cl03g7NoYzDq1zUmGSXhvb418XCSL7e4S0EF\n"
"q6meNQhY7LEqxGiHC6PjdeTm86dicbp5gWAf15Gan/PQeGdxyGkOlZHP/uaZ6WA8\n"
"SMx+yk13EiSdRxta67nsHjcAHJyse6cF6s5K671B5TaYucv9bTyWaN8jKkKQDIZ0\n"
"Z8h/pZq4UmEUEz9l6YKHy9v6Dlb2honzhT+Xhq+w3Brvaw2VFn3EK6BlspkENnWA\n"
"a6xK8xuQSXgvopZPKiAlKQTGdMDQMc2PMTiVFrqoM7hD8bEfwzB/onkxEz0tNvjj\n"
"/PIzark5McWvxI0NHWQWM6r6hCm21AvA2H3DkwIDAQABo4IBfTCCAXkwEgYDVR0T\n"
"AQH/BAgwBgEB/wIBADAOBgNVHQ8BAf8EBAMCAYYwfwYIKwYBBQUHAQEEczBxMDIG\n"
"CCsGAQUFBzABhiZodHRwOi8vaXNyZy50cnVzdGlkLm9jc3AuaWRlbnRydXN0LmNv\n"
"bTA7BggrBgEFBQcwAoYvaHR0cDovL2FwcHMuaWRlbnRydXN0LmNvbS9yb290cy9k\n"
"c3Ryb290Y2F4My5wN2MwHwYDVR0jBBgwFoAUxKexpHsscfrb4UuQdf/EFWCFiRAw\n"
"VAYDVR0gBE0wSzAIBgZngQwBAgEwPwYLKwYBBAGC3xMBAQEwMDAuBggrBgEFBQcC\n"
"ARYiaHR0cDovL2Nwcy5yb290LXgxLmxldHNlbmNyeXB0Lm9yZzA8BgNVHR8ENTAz\n"
"MDGgL6AthitodHRwOi8vY3JsLmlkZW50cnVzdC5jb20vRFNUUk9PVENBWDNDUkwu\n"
"Y3JsMB0GA1UdDgQWBBSoSmpjBH3duubRObemRWXv86jsoTANBgkqhkiG9w0BAQsF\n"
"AAOCAQEA3TPXEfNjWDjdGBX7CVW+dla5cEilaUcne8IkCJLxWh9KEik3JHRRHGJo\n"
"uM2VcGfl96S8TihRzZvoroed6ti6WqEBmtzw3Wodatg+VyOeph4EYpr/1wXKtx8/\n"
"wApIvJSwtmVi4MFU5aMqrSDE6ea73Mj2tcMyo5jMd6jmeWUHK8so/joWUoHOUgwu\n"
"X4Po1QYz+3dszkDqMp4fklxBwXRsW10KXzPMTZ+sOPAveyxindmjkW8lGy+QsRlG\n"
"PfZ+G6Z6h7mjem0Y+iWlkYcV4PIWL1iwBi8saCbGS5jN2p8M+X+Q7UNKEkROb3N6\n"
"KOqkqm57TH2H3eDJAkSnh6/DNFu0Qg==\n"
"-----END CERTIFICATE-----\n";
// You can use x.509 client certificates if you want
//const char* test_client_key = ""; //to verify the client
//const char* test_client_cert = ""; //to verify the client
String data;
WiFiClientSecure client;
void setup() {
//Initialize serial and wait for port to open:
Serial.begin(115200);
delay(100);
pinMode(WIO_KEY_C, INPUT_PULLUP);
Serial.print("Attempting to connect to SSID: ");
Serial.println(ssid);
WiFi.begin(ssid, password);
tft.begin();
tft.setRotation(3);
tft.fillScreen(TFT_BLACK);
tft.setFreeFont(FMB12);
tft.setCursor((320 - tft.textWidth("Connecting to Wi-Fi.."))/2, 120);
tft.print("Connecting to Wi-Fi..");
// attempt to connect to Wifi network:
while (WiFi.status() != WL_CONNECTED) {
Serial.print(".");
// wait 1 second for re-trying
delay(1000);
}
Serial.print("Connected to ");
Serial.println(ssid);
tft.fillScreen(TFT_BLACK);
tft.setCursor((320 - tft.textWidth("Connected!"))/2, 120);
tft.print("Connected!");
getData();
}
int lastState = 1;
void loop()
{
int currentState = digitalRead(WIO_KEY_C);
if (currentState == 0) {
if (currentState != lastState) {
getData();
}
lastState = !lastState;
}
}
void getData() {
client.setCACert(test_root_ca);
//client.setCertificate(test_client_key); // for client verification
//client.setPrivateKey(test_client_cert); // for client verification
tft.fillScreen(TFT_BLACK);
tft.setTextColor(TFT_WHITE);
tft.setCursor((320 - tft.textWidth("Conectting to Server.."))/2, 120);
tft.print("Connecting to Server..");
Serial.println("\nStarting connection to server...");
if (!client.connect(server, 443)) {
Serial.println("Connection failed!");
tft.fillScreen(TFT_BLACK);
tft.setCursor((320 - tft.textWidth("Connection failed!"))/2, 120);
tft.print("Connection failed!");
} else {
Serial.println("Connected to server!");
tft.fillScreen(TFT_BLACK);
tft.setCursor((320 - tft.textWidth("Connected to Server!"))/2, 120);
tft.print("Connected to Server!");
// Make a HTTP request:
client.println("GET https://api.covid19api.com/world/total HTTP/1.0");
client.println("Host: api.covid19api.com");
client.println("Connection: close");
client.println();
while (client.connected()) {
String line = client.readStringUntil('\n');
if (line == "\r") {
Serial.println("headers received");
break;
}
}
while(client.available())
{
String line = client.readStringUntil('\r');
data = line;
}
Serial.println(data);
client.stop();
Serial.println("closing connection");
}
//ArduinoJson to parse data, plesae check ArduinoJson for more info
const size_t capacity = JSON_OBJECT_SIZE(3) + 50;
DynamicJsonDocument doc(capacity);
deserializeJson(doc, data);
long TotalConfirmed = doc["TotalConfirmed"];
long TotalDeaths = doc["TotalDeaths"];
long TotalRecovered = doc["TotalRecovered"];
// -----------------LCD---------------------
tft.fillScreen(tft.color565(24,15,60));
tft.setFreeFont(FF17);
tft.setTextColor(tft.color565(224,225,232));
tft.drawString("COVID-19 Dashboard/Global",20,10);
tft.fillRoundRect(10, 45, 300, 55, 5, tft.color565(40,40,86));
tft.fillRoundRect(10, 105, 300, 55, 5, tft.color565(40,40,86));
tft.fillRoundRect(10, 165, 300, 55, 5, tft.color565(40,40,86));
tft.setFreeFont(FM9);
tft.drawString("Total Confirmed", 75, 50);
tft.drawString("Total Deaths",95, 110);
tft.drawString("Total Recovered",75, 170);
tft.setFreeFont(FMB12);
tft.setTextColor(TFT_RED);
tft.drawNumber(TotalConfirmed, 110, 75);
tft.setTextColor(tft.color565(224,225,232));
tft.drawNumber(TotalDeaths, 120, 135);
tft.setTextColor(TFT_GREEN);
tft.drawNumber(TotalRecovered, 110, 195);
}