The ADC will be stable when the sample is repeated before settling, the averaging of 100 readings over each of the 4 pins (32,33,34,35) with 5ms timer varies less than 5/4095.
5ms is the limit for the 4 pins to complete and not fire the WDT.
This sketch was based on the SimpleWifiServer Example with snippets from the RepeatTimer Example and some SDK system variables.
Code: Select all
/*
WiFi Web Server LED Blink
A simple web server that lets you blink an LED via the web.
This sketch will print the IP address of your WiFi Shield (once connected)
to the Serial monitor. From there, you can open that address in a web browser
to turn on and off the LED on pin 5.
If the IP address of your shield is yourAddress:
http://yourAddress/H turns the LED on
http://yourAddress/L turns it off
This example is written for a network using WPA encryption. For
WEP or WPA, change the Wifi.begin() call accordingly.
Circuit:
* WiFi shield attached
* LED attached to pin 5
created for arduino 25 Nov 2012
by Tom Igoe
ported for sparkfun esp32
31.01.2017 by Jan Hendrik Berlin
*/
#include "esp_system.h"
#include <WiFi.h>
const char* ssid = "SSID";
const char* password = "PASSWORD";
int *aDcData0;
int *aDcData1;
int *aDcData2;
int *aDcData3;
long int total0,total1,total2,total3;
int SampleCount = 100;
int y,y2,record;
unsigned long ulMeasCount=0;
unsigned long ulNextMeas_ms=0;
//int ReFresh = 10;
int siZe = 1000;
WiFiServer server(80);
hw_timer_t * timer = NULL;
void GetReading(){
ulMeasCount++;
if(ulMeasCount>(siZe-1)){ulMeasCount=1;clearArray();}
for(int i=0;i<SampleCount;i++){
total0 += analogRead(32); // Read ADC4
total1 += analogRead(33); // Read ADC5
total2 += analogRead(34); // Read ADC6
total3 += analogRead(35); // Read ADC7
}
aDcData0[ulMeasCount] = total0 / SampleCount;
aDcData1[ulMeasCount] = total1 / SampleCount;
aDcData2[ulMeasCount] = total2 / SampleCount;
aDcData3[ulMeasCount] = total3 / SampleCount;
total0=0;
total1=0;
total2=0;
total3=0;
}
void clearArray(){
for(int i=0;i<siZe;i++){
aDcData0[i]=0;
aDcData1[i]=0;
aDcData2[i]=0;
aDcData3[i]=0;
}
}
void setup()
{
Serial.begin(115200);
pinMode(LED_BUILTIN, OUTPUT); // set the LED pin mode
delay(10);
// We start by connecting to a WiFi network
Serial.println();
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
server.begin();
aDcData0 = new int[siZe];
aDcData1 = new int[siZe];
aDcData2 = new int[siZe];
aDcData3 = new int[siZe];
clearArray();
// Use 1st timer of 4 (counted from zero).
// Set 80 divider for prescaler (see ESP32 Technical Reference Manual for more
// info).
timer = timerBegin(0, 80, true);
// Attach onTimer function to our timer.
timerAttachInterrupt(timer, &GetReading, true);
// Set alarm to call onTimer function every second (value in microseconds).
// Repeat the alarm (third parameter)
timerAlarmWrite(timer, 5000, true); // 2 milliseconds
// Start an alarm
timerAlarmEnable(timer);
}
int value = 0;
int val = 0;
void loop(){
WiFiClient client = server.available(); // listen for incoming clients
if (client) { // if you get a client,
//val = hallRead(); // Read Hall Sensor
IPAddress ip = WiFi.localIP(); // IP to display
FlashMode_t ideMode = ESP.getFlashChipMode();
Serial.println("new client"); // print a message out the serial port
String currentLine = ""; // make a String to hold incoming data from the client
while (client.connected()) { // loop while the client's connected
if (client.available()) { // if there's bytes to read from the client,
char c = client.read(); // read a byte, then
Serial.write(c); // print it out the serial monitor
if (c == '\n') { // if the byte is a newline character
// if the current line is blank, you got two newline characters in a row.
// that's the end of the client HTTP request, so send a response:
if (currentLine.length() == 0) {
// HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
// and a content-type so the client knows what's coming, then a blank line:
client.println("HTTP/1.1 200 OK");
client.println("Content-type:text/html");
client.println();
// the content of the HTTP response follows the header:
int adcnum=3;
for(int loOp=32;loOp<36;loOp++){
String out = "";
char temp[100];
int dIspV;
if(loOp==32) { y = aDcData0[1] / 30; dIspV=aDcData0[ulMeasCount];}
else if(loOp==33) { y = aDcData1[1] / 30; dIspV=aDcData1[ulMeasCount];}
else if(loOp==34) { y = aDcData2[1] / 30; dIspV=aDcData2[ulMeasCount];}
else if(loOp==35) { y = aDcData3[1] / 30; dIspV=aDcData3[ulMeasCount];}
client.print("ADC");
client.print(adcnum++);
client.print(" Last Value Sampled on pin ");
client.print(loOp);
client.print(" : ");
client.print(dIspV);
client.print("<BR>");
out += "<svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" width=\"1000\" height=\"150\">\n";
out += "<rect width=\"1000\" height=\"150\" fill=\"rgb(250, 230, 210)\" stroke-width=\"1\" stroke=\"rgb(0, 0, 0)\" />\n";
out += "<g stroke=\"black\">\n";
record = 2;
for (int x = 1; x < ulMeasCount; x+=1) {
if(loOp==32) { y2 = aDcData0[record] / 30;}
else if(loOp==33) { y2 = aDcData1[record] / 30;}
else if(loOp==34) { y2 = aDcData2[record] / 30;}
else if(loOp==35) { y2 = aDcData3[record] / 30;}
sprintf(temp, "<line x1=\"%d\" y1=\"%d\" x2=\"%d\" y2=\"%d\" stroke-width=\"1\" />\n", x, 140 - y, x + 1, 140 - y2);
out += temp;
y = y2;
record++;
if(out.length()>2000){
client.print(out);
out="";
}
}
out += "</g>\n</svg><BR>";
client.print(out);
}
client.print("<BR>Click <a href=\"/H\">here</a> turn the Onboard LED on<br>");
client.print("Click <a href=\"/L\">here</a> turn the Onboard LED off<br>");
// client.print("Hall Sensor Value : ");
//client.print(String(val));
client.print("<BR>Local IP Address : ");
client.print(ip);
client.print("<BR> Free RAM = ");
client.print((uint32_t)system_get_free_heap_size() / 1024);
client.print(" KB<BR> SDK Version = ");
client.print(ESP.getSdkVersion());
client.print("<BR>");
client.printf(" Flash Chip Mode = %s\n", (ideMode == FM_QIO ? "QIO" : ideMode == FM_QOUT ? "QOUT" : ideMode == FM_DIO ? "DIO" : ideMode == FM_DOUT ? "DOUT" : "UNKNOWN"));
client.print("<BR> Flash Size (IDE) = ");
client.print(ESP.getFlashChipSize()/1024);
client.print(" KBytes<BR> Flash Speed = ");
client.print(ESP.getFlashChipSpeed()/1000000);
client.print("MHz<BR>");
// The HTTP response ends with another blank line:
client.println();
// break out of the while loop:
break;
} else { // if you got a newline, then clear currentLine:
currentLine = "";
}
} else if (c != '\r') { // if you got anything else but a carriage return character,
currentLine += c; // add it to the end of the currentLine
}
// Check to see if the client request was "GET /H" or "GET /L":
if (currentLine.endsWith("GET /H")) {
digitalWrite(LED_BUILTIN, HIGH); // GET /H turns the LED on
// put your main code here, to run repeatedly:
}
if (currentLine.endsWith("GET /L")) {
digitalWrite(LED_BUILTIN, LOW); // GET /L turns the LED off
}
}
}
// close the connection:
client.stop();
Serial.println("client disonnected");
}
}