RE: Simple PWM

parman — Wed, 01 May 2019 15:14:26 GMT

Thank You for your guidance Mr. Awneil. I will follow your steps and reply back.

RE: Simple PWM

awneil — Wed, 01 May 2019 09:14:43 GMT

[quote userid="78795" url="~/f/nordic-q-a/46740/simple-pwm/184671"]nrf_drv_pwm.h: No such file or directory[/quote]

Answered in your ADC thread: https://devzone.nordicsemi.com/f/nordic-q-a/46716/simple-adc-code/184681#184681

[quote userid="78795" url="~/f/nordic-q-a/46740/simple-pwm/184671"]I am new[/quote]

Here are some 'C' learning & reference materials for you:

http://blog.antronics.co.uk/category/c-programming/

Also, some microcontroller "getting started" tips:

https://www.avrfreaks.net/comment/2079906#comment-2079906

How to properly post source code:

RE: Simple PWM

parman — Wed, 01 May 2019 07:45:39 GMT

Hello,

Glad to hear from you

But I am unable to open the page saying the -

Access Denied

But I found some code -

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

#include <stdio.h>
#include <string.h>
#include "nrf_drv_pwm.h"
#include "app_util_platform.h"
#include "app_error.h"
#include "boards.h"
#include "bsp.h"
#include "nrf_drv_clock.h"
#include "nrf_delay.h"

#define OUTPUT_PIN LED_1

static nrf_drv_pwm_t m_pwm0 = NRF_DRV_PWM_INSTANCE(0);

// Declare variables holding PWM sequence values. In this example only one channel is used
nrf_pwm_values_individual_t seq_values[] = {0, 0, 0, 0};
nrf_pwm_sequence_t const seq =
{
.values.p_individual = seq_values,
.length = NRF_PWM_VALUES_LENGTH(seq_values),
.repeats = 0,
.end_delay = 0
};

// Set duty cycle between 0 and 100%
void pwm_update_duty_cycle(uint8_t duty_cycle)
{

// Check if value is outside of range. If so, set to 100%
if(duty_cycle >= 100)
{
seq_values->channel_0 = 100;
}
else
{
seq_values->channel_0 = duty_cycle;
}

nrf_drv_pwm_simple_playback(&m_pwm0, &seq, 1, NRF_DRV_PWM_FLAG_LOOP);
}

static void pwm_init(void)
{
nrf_drv_pwm_config_t const config0 =
{
.output_pins =
{
OUTPUT_PIN, // channel 0
NRF_DRV_PWM_PIN_NOT_USED, // channel 1
NRF_DRV_PWM_PIN_NOT_USED, // channel 2
NRF_DRV_PWM_PIN_NOT_USED, // channel 3
},
.irq_priority = APP_IRQ_PRIORITY_LOWEST,
.base_clock = NRF_PWM_CLK_1MHz,
.count_mode = NRF_PWM_MODE_UP,
.top_value = 100,
.load_mode = NRF_PWM_LOAD_INDIVIDUAL,
.step_mode = NRF_PWM_STEP_AUTO
};
// Init PWM without error handler
APP_ERROR_CHECK(nrf_drv_pwm_init(&m_pwm0, &config0, NULL));

}

int main(void)
{

// Start clock for accurate frequencies
NRF_CLOCK->TASKS_HFCLKSTART = 1;
// Wait for clock to start
while(NRF_CLOCK->EVENTS_HFCLKSTARTED == 0)
;

pwm_init();

for (;;)
{
for(int i = 0; i <= 100; i++)
{
nrf_delay_ms(10);
pwm_update_duty_cycle(i);
}
}
}

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

But I got some errors -

Rebuilding ‘blinky_pca10059_mbr’ from solution ‘blinky_pca10059_mbr’ in configuration ‘Release’
Assembling ‘thumb_crt0.s’
Compiling ‘nrf_log_frontend.c’
Compiling ‘nrf_log_str_formatter.c’
Compiling ‘boards.c’
Compiling ‘app_error.c’
Compiling ‘app_error_handler_gcc.c’
Compiling ‘app_error_weak.c’
Compiling ‘app_util_platform.c’
Compiling ‘nrf_assert.c’
Compiling ‘nrf_atomic.c’
Compiling ‘nrf_balloc.c’
Compiling ‘nrf_fprintf.c’
Compiling ‘nrf_fprintf_format.c’
Compiling ‘nrf_memobj.c’
Compiling ‘nrf_ringbuf.c’
Compiling ‘nrf_strerror.c’
Compiling ‘nrfx_atomic.c’
Compiling ‘main.c’
nrf_drv_pwm.h: No such file or directory
Build failed

But I am new so I am not able to figure out the errors. Sorry. Kindly guide me.

Waiting for your quick response

RE: Simple PWM

ovrebekk — Tue, 30 Apr 2019 13:29:46 GMT

Hi Parman

I shared a simple PWM example a couple of months ago:
https://devzone.nordicsemi.com/support-private/support/221537

Please take a look at that 🙂

Best regards
Torbjørn