AnalogWrite vs DigitalWrite
- Thread starter BrianDen
- Start date
analogWrite is 10bit by default i believe, so a value of 256 would be rather dim even more so a value of 128.
if you want to blink a LED (just on and off) it is simpler to use digitalWrite (the blink example)
if you need it non blocking, you can use an elapsedMillis variable and check it's value to decide if the LED should be on or off i.e. something like this (not tested)
if you want to blink a LED (just on and off) it is simpler to use digitalWrite (the blink example)
Code:
/*
Blink ADAPTED with elapsedMillis for nonblocking blink
Turns an LED on for one second, then off for one second, repeatedly.
Most Arduinos have an on-board LED you can control. On the UNO, MEGA and ZERO
it is attached to digital pin 13, on MKR1000 on pin 6. LED_BUILTIN is set to
the correct LED pin independent of which board is used.
If you want to know what pin the on-board LED is connected to on your Arduino
model, check the Technical Specs of your board at:
https://www.arduino.cc/en/Main/Products
modified 8 May 2014
by Scott Fitzgerald
modified 2 Sep 2016
by Arturo Guadalupi
modified 8 Sep 2016
by Colby Newman
This example code is in the public domain.
https://www.arduino.cc/en/Tutorial/BuiltInExamples/Blink
*/
// the setup function runs once when you press reset or power the board
void setup() {
// initialize digital pin LED_BUILTIN as an output.
pinMode(LED_BUILTIN, OUTPUT);
}
// the loop function runs over and over again forever
void loop() {
digitalWrite(LED_BUILTIN, HIGH); // turn the LED on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(LED_BUILTIN, LOW); // turn the LED off by making the voltage LOW
delay(1000); // wait for a second
}if you need it non blocking, you can use an elapsedMillis variable and check it's value to decide if the LED should be on or off i.e. something like this (not tested)
Code:
/*
Blink
Turns an LED on for one second, then off for one second, repeatedly.
Most Arduinos have an on-board LED you can control. On the UNO, MEGA and ZERO
it is attached to digital pin 13, on MKR1000 on pin 6. LED_BUILTIN is set to
the correct LED pin independent of which board is used.
If you want to know what pin the on-board LED is connected to on your Arduino
model, check the Technical Specs of your board at:
https://www.arduino.cc/en/Main/Products
modified 8 May 2014
by Scott Fitzgerald
modified 2 Sep 2016
by Arturo Guadalupi
modified 8 Sep 2016
by Colby Newman
This example code is in the public domain.
https://www.arduino.cc/en/Tutorial/BuiltInExamples/Blink
*/
// time the LED blink with a elapsedMillis variable
elapsedMillis check_seconds = 0;
bool on_off = 0;
// the setup function runs once when you press reset or power the board
void setup() {
// initialize digital pin LED_BUILTIN as an output.
pinMode(LED_BUILTIN, OUTPUT);
}
// the loop function runs over and over again forever
void loop() {
// turn the LED on (HIGH is the voltage level)
if ((check_seconds < 500) && !on_off) {
digitalWrite(LED_BUILTIN, HIGH);
on_off = 1;
}
if ((check_seconds > 500) && on_off) {
digitalWrite(LED_BUILTIN, LOW); // turn the LED off by making the voltage LOW
on_off = 0;
}
if (check_seconds >= 1000) check_seconds = 0;
}My outputs control mosfets, where some drice 15a load. I would like to use soft start so devices dont get full voltage immediatly. So i would like to use pwm to drive them up to full voltage
PaulStoffregen
Well-known member
Unfortunately no, 1 Hz PWM won't work.
PWM is meant for kHz to MHz range and has a fairly high minimum frequency.