how to define gpio pins and generate pwm on gpio pins?

[ASHISH]

Hi There, i am new to nrf51822 and new to program this kind of controller.I searched over the website, I couldn't find a good introductory documentation for programming the nrf51822, specifically the nrf51-dk. i have two problems 1.i want to connect a led and buzzer to gpio pins of nrf51822 so how to declare gpio pins in program for ex. suppose if i press button on nrf board the buzzer connected to gpio pins (for (ex. p0.0) should be on (make some sound). 2.i want to generate a pwm on gpio pin (for ex on p0.1) how to declare this pin as output for pwm how to use functions to declare gpio,led and other stuff as i gone through the tutorial it is not well defined and the tutorials are very much confused and easy to understandable can anybody give me the good explnation about this a good tutorial with each and every line explained will be great help!! Regards, Abhijeet Kapse

[Sigurd]

Hi,

As an introduction, I would recommend the Getting Started guide and our examples in the SDK. For PWM generation on the nRF51, you should take a look at the PWM library example. You can find the example in the folder: <SDK_InstallFolder>\examples\peripheral\pwm_library

[Sigurd]

I would recommend using the PWM library for generating a PWM pulse. nrf_delay_ms will keep the CPU active, and consume much more power. nrf_delay_ms is also not very accurate.

But you can get your code to work like this:

#include <stdbool.h>
#include <stdint.h>
#include "nrf.h"
#include "app_error.h"
#include "bsp.h"
#include "nrf_delay.h"
#include "app_pwm.h"

#define pin_number1 1
int main(){

nrf_gpio_cfg_output(pin_number1);
    while(true){
for(int i=0;i<=20;i++){
    nrf_gpio_pin_set(pin_number1);
    nrf_delay_ms(10);
    nrf_gpio_pin_clear(pin_number1);
    nrf_delay_ms(20);
    }
}
}