I'm so new to this, so I'm sorry for the low-level question.
I got the value of the sensor as a number in Arduino and made it float in the ip address window.
The current situation is as follows.
ex)
Link 1: http://111.111.111.111
Link 2: http://111.111.111.111/value
Link 1 showed all the measured sensor values, and if a specific value or higher comes out, it was recorded separately at the bottom.
Link 2 has made only the numerical values of the current sensor output.
In Web viewer 1, I type link 1 in url and see it as the default screen of the app,
In web1 (connectivity), I want to type link 2 to make the app inventory go to the alarm when the value of the numerical value is above 50.
However, there seems to be a problem that the value output on link 2 is a number, but it is treated as a string value, so it does not work as I want.
So I need to convert the string value in link 2 to a number but I don't know how.
The picture below is the block code I have made now.
I would appreciate it if you could suggest a solution.
Or if you can proceed in a different way, I would greatly appreciate it if you could also tell me how to do it.
What did you get when you test the above code?
Doesnot work?
Especially with web got text
The result value of the sensor received from the /value link seems to be accepted as a character, not a number, within the App Inventor.
In the /value link, only numbers are output, but this value seems to be treated as a character, not a number.
I want to know how to convert this character into a number.
When I run the simulation with the app I created, the alarm does not come even if the sensor's result value is more than 50.
This is arduino code
#include <WiFiNINA.h>
#include <WiFiUdp.h>
#include <NTPClient.h>
char ssid[x] = "U+NetF4E8";
char pass[ ] = "";
int status = WL_IDLE_STATUS;
WiFiServer server(80);
const int sensorPin = A0;
// NTP ์ค์
WiFiUDP ntpUDP;
NTPClient timeClient(ntpUDP, "pool.ntp.org", 9 * 3600, 60000); // UTC+9 (ํ๊ตญ ์๊ฐ)
// ๋ก๊ทธ ๊ตฌ์กฐ
#define MAX_LOGS 10
struct SensorLog {
int value;
String timestamp;
};
SensorLog sensorLogs[MAX_LOGS];
int logIndex = 0;
void setup() {
Serial.begin(115200);
while (status != WL_CONNECTED) {
Serial.print("Connecting to: ");
Serial.println(ssid);
status = WiFi.begin(ssid, pass);
delay(1000);
}
Serial.println("Connected!");
timeClient.begin();
timeClient.update();
server.begin();
}
void loop() {
timeClient.update();
WiFiClient client = server.available();
if (client) {
Serial.println("New client connected");
String request = "";
while (client.connected()) {
if (client.available()) {
char c = client.read();
request += c;
if (request.endsWith("\r\n\r\n")) {
int sensorValue = analogRead(sensorPin);
String nowTime = getFormattedDateTime();
// 40 ์ด์์ด๋ฉด ๊ธฐ๋ก ์ ์ฅ
if (sensorValue >= 40) {
sensorLogs[logIndex].value = sensorValue;
sensorLogs[logIndex].timestamp = nowTime;
logIndex = (logIndex + 1) % MAX_LOGS;
}
// /value: ์ซ์๋ง ์๋ต
if (request.indexOf("GET /value ") >= 0) {
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/plain");
client.println("Connection: close");
client.println();
client.println(sensorValue);
}
// /valuehtml: ์ซ์๋ง ํฐ ๊ธ์จ + ์๋ ์๋ก๊ณ ์นจ
else if (request.indexOf("GET /valuehtml") >= 0) {
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html");
client.println("Connection: close");
client.println();
client.println("<html><head>");
client.println("<meta http-equiv='refresh' content='5'>");
client.println("<title>Sensor Value</title></head><body>");
client.print("<h1 style='font-size:80px; text-align:center;'>");
client.print(sensorValue);
client.println("</h1>");
client.println("</body></html>");
}
// ๊ธฐ๋ณธ ํ์ด์ง (/): ์น์ฌ์ดํธ ์ ์ฒด
else {
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html; charset=utf-8");
client.println("Connection: close");
client.println();
client.println("<html><head><meta http-equiv='refresh' content='5'></head><body>");
client.println("<h1>FC-22 CO Sensor</h1>");
client.print("<p><b>Current Time:</b> ");
client.print(nowTime);
client.println("</p>");
client.print("<p><b>Sensor Value:</b> ");
client.print(sensorValue);
client.println("</p>");
if (sensorValue > 40) {
client.println("<p style='color:red; font-weight:bold;'>โ ๏ธ Warning: CO level is high! Please ventilate the area!</p>");
}
client.println("<hr><h3>Recent High Values (โฅ40)</h3><ul>");
for (int i = 0; i < MAX_LOGS; i++) {
int idx = (logIndex + i) % MAX_LOGS;
if (sensorLogs[idx].value >= 40) {
client.print("<li>");
client.print(sensorLogs[idx].timestamp);
client.print(" - ");
client.print(sensorLogs[idx].value);
client.println("</li>");
}
}
client.println("</ul></body></html>");
}
break;
}
}
}
delay(10);
client.stop();
Serial.println("Client disconnected");
}
}
// ๋ ์ง ๋ฐ ์๊ฐ ํฌ๋งท
String getFormattedDateTime() {
unsigned long epochTime = timeClient.getEpochTime();
int currentHour = (epochTime % 86400L) / 3600;
int currentMinute = (epochTime % 3600) / 60;
int currentSecond = epochTime % 60;
int days = epochTime / 86400L;
int year = 1970;
while (true) {
bool leap = (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
int daysInYear = leap ? 366 : 365;
if (days >= daysInYear) {
days -= daysInYear;
year++;
} else {
break;
}
}
int month = 0;
int day = 0;
int monthLength[] = {31,28,31,30,31,30,31,31,30,31,30,31};
if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) {
monthLength[1] = 29;
}
for (int i = 0; i < 12; i++) {
if (days >= monthLength[i]) {
days -= monthLength[i];
} else {
month = i + 1;
day = days + 1;
break;
}
}
char buffer[25];
sprintf(buffer, "%04d-%02d-%02d %02d:%02d:%02d",
year, month, day, currentHour, currentMinute, currentSecond);
return String(buffer);
}
It's a block code that I've changed to get push notifications, but I still don't get notifications when the sensor's value exceeds 40.
In the web got text first catch the response content on a label/global variable to know actually what does it return so that we can suggest you better.
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