Peter Xian

Important changes to forums and questions

All forums and questions are now archived. To start a new conversation or read the latest updates go to forums.mbed.com.

9 years ago.

Source Code of AnalogIn

Hi, Does anyone where the source code of this analogIn is? I want to learn about how mbed programs the ADC.

Question relating to:

Last updated: 30 Apr 2020

1 Answer

Sam Grove
9 years ago.

I'd suggest importing a program such as this: http://developer.mbed.org/users/thudt90/code/mbed_blinky/

From there use the text navigation in the online IDE to jump around and see what calls are being made. Make sure to update mbed-src as your platform may not have been present when this program was published.

Accepted Answer

Hi Sam,

The blinky code does not use any analogIn there. Is this what you intended me to look over?

posted by Peter Xian 10 Apr 2015

Just add your own Analog in code or start from an example snippet and start clicking around. Here is the documentation: http://developer.mbed.org/handbook/AnalogIn

#include "mbed.h"
 
// Initialize a pins to perform analog input and digital output fucntions
AnalogIn   ain(A0);
DigitalOut dout(LED1);
 
int main(void)
{
    while (1) {
        // test the voltage on the initialized analog pin
        //  and if greater than 0.3 * VCC set the digital pin
        //  to a logic 1 otherwise a logic 0
        if(ain > 0.3f) {
            dout = 1;
        } else {
            dout = 0;
        }
        
        // print the percentage and 16 bit normalized values
        printf("percentage: %3.3f%%\n", ain.read()*100.0f);
        printf("normalized: 0x%04X \n", ain.read_u16());
        wait(0.2f);
    }
}
posted by Sam Grove 10 Apr 2015