element14's The Ben Heck Show

Forum DAC

Join element14's The Ben Heck Show to participate - click to join for free!

Actions

Forum Thread Details

Replies 10 replies
Subscribers 32 subscribers
Views 859 views
Users 0 members are here

Related

DAC

royston02 over 11 years ago

I wanted to know how can I turn an analog input to output or a digital IO(without pwm)to pwm signals using arduino

Top Replies

vitormhenrique over 11 years ago +1

You need to work on your question. First: An analog input on arduino is "like" an voltage meter, instead of reading if the pin is HIGH (5V) or LOW (0V) it will measure the intermediate voltage. Regarding…
royston02 over 11 years ago in reply to vitormhenrique +1

Just want to turn any IO into PWM(not just dedicated pwm pinouts) life pin 36 of mega
colecago over 11 years ago in reply to royston02 +1

Look up software PWM.

Parents

vitormhenrique over 11 years ago

You need to work on your question.

First: An analog input on arduino is "like" an voltage meter, instead of reading if the pin is HIGH (5V) or LOW (0V) it will measure the intermediate voltage.

Regarding the "without pwm IO" i think you mean "hardware PWM". Arduino have some pins that can candle hardware PWM (Arduino - AnalogWrite) and there are some libraries to use a "Software PWM" so you can use any IO (SoftPWM Library - Arduino Forum).

I think the question is how do you wanna translate between the analog value to the PWM? An example could be use a potentiometer to control a Servo like this:

Arduino - Knob

Or using a potentiometer to control a led brightness.... or something else.... you need to explain what is your goal to actually help you...
Cancel
Vote Up +1 Vote Down

Sign in to reply

Cancel
royston02 over 11 years ago in reply to vitormhenrique

Just want to turn any IO into PWM(not just dedicated pwm pinouts) life pin 36 of mega
Cancel
Vote Up +1 Vote Down

Sign in to reply

Cancel

Reply

royston02 over 11 years ago in reply to vitormhenrique

Just want to turn any IO into PWM(not just dedicated pwm pinouts) life pin 36 of mega
Cancel
Vote Up +1 Vote Down

Sign in to reply

Cancel

Children

colecago over 11 years ago in reply to royston02

Look up software PWM.
Cancel
Vote Up +1 Vote Down

Sign in to reply

Cancel
royston02 over 11 years ago in reply to colecago

I don't really understand it
Cancel
Vote Up 0 Vote Down

Sign in to reply

Cancel
Kilohercas over 11 years ago in reply to royston02

yeah, that is typical arduino user

int number_of_points = 1024;

float duty_cycle = 0.5f;
int frequency =1;
int i = 0;
int temp = (int)number_of_points*duty_cycle;
while(1)
{
     gpio_high();// Set gpio high, i don't know sintax for arduino
    while(i<temp)
    {
        i++;
        delay_us(frequency);
    }
    gpio_low();// Set gpio low, i don't know sintax for arduino
    while(i<number_of_points)
    {
        i++;
        delay_us(frequency);
    }
    i=0;
}
this is no way optimized, only to show the idea. with optimization it could make 10x higher frequency pwm signal
Cancel
Vote Up 0 Vote Down

Sign in to reply

Cancel