Hi Guys,
I have a trouble with generating signal from Arduino Uno using digitalWrite() and timer using millis(). [ I tried did it using delay() method but there was same result].
First of all, My task is to generate identical signal as on the screen below :
So I made measurements on the oscilloscope and I split the signal into logical 0 and 1.
Then using extra tools I got finally that one logic signal lasts 0.4 ms.
I had all I need so lets begin coding.
This is my code, It waits 5 seconds then generates my signal, but to interval = 1 everything was fine, then the signal frequency is constant despite the interval changes. My code below :
Paweł Bocian <boocianpawel@gmail.com>
00:23 (0 minut temu)
do mnie
const int signalPin = 13; // the number of the Signal pin output
const int onSignal[180] = {0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,1};
// Variables will change:
int outputState = HIGH; // outputState used to set the signal
long previousMillis = 0; // will store last time signal was updated
int countDown =0; // temporary variable
int iterator =0; // Iterator thought signal
//Time variabl3
long interval = 8.9;
long begintime = 0;
long firstSignalTime =0;
long lastSignalTime =0;
void setup() {
// put your setup code here, to run once:
pinMode(signalPin, OUTPUT);
Serial.begin(115200);
}
void loop() {
// put your main code here, to run repeatedly:
if(countDown == 5){
firstSignalTime = millis();
while(iterator < 180){
unsigned long currentMillis = millis();
if(currentMillis - previousMillis > interval) {
// save the last time you change signal
previousMillis = currentMillis;
// if the signal is 0 generate LOW signal and vice-versa.
if (onSignal[iterator] == 0)
outputState = LOW;
else
outputState = HIGH;
// set the signal with the sigalState of the variable:
digitalWrite(signalPin, outputState);
Serial.println(iterator);
iterator++;
countDown++;
}
}
lastSignalTime = millis();
}else {
Serial.print("Jeszcze nie : ");
Serial.println(countDown);
Serial.print("FirstSignal at : ");
Serial.println(firstSignalTime);
Serial.print("LastSignal at : ");
Serial.println(lastSignalTime);
delay(1000);
countDown++;
}
}
There is some extra variables to measure if my "delay" works.
My question is how to generate signal like from the picture ? I have also ESP8266 nodeMcu v3 but its quite similar device.
Extra pic : differences-in-signal-period hosted at ImgBB — ImgBB
White signal - original signal from IR diode,
Yellow signal - my signal generated
