hello, I want to generate a square wave; examples of your company use PWM official offer;Square wave frequency lower accuracy, configuration 10KHz frequency, there will be error ± 16Hz.How do I need to configure the frequency accuracy can reach ± 1Hz? Here is the code:
void demo1(void)
{
printf("Demo 1\r\n");
/*
* This demo plays back a sequence with different values for individual
* channels (LED 1 - LED 4). Only four values are used (one per channel).
* Every time the values are loaded into the compare registers, they are
* updated in the provided event handler. The values are updated in such
* a way that increase and decrease of the light intensity can be observed
* continuously on succeeding channels (one second per channel).
*/
uint32_t err_code;
nrf_drv_pwm_config_t const config0 =
{
.output_pins =
{
BSP_LED_0 | NRF_DRV_PWM_PIN_INVERTED, // channel 0
BSP_LED_1 | NRF_DRV_PWM_PIN_NOT_USED, // channel 1
BSP_LED_3 | NRF_DRV_PWM_PIN_NOT_USED, // channel 2
BSP_LED_2 | NRF_DRV_PWM_PIN_NOT_USED // channel 3
},
.irq_priority = _PRIO_APP_HIGH,
.base_clock = PWM_PRESCALER_PRESCALER_DIV_1,
.count_mode = NRF_PWM_MODE_UP,
.top_value = 100,
.load_mode = NRF_PWM_LOAD_INDIVIDUAL,
.step_mode = NRF_PWM_STEP_AUTO
};
err_code = nrf_drv_pwm_init(&m_pwm0, &config0, NULL);
APP_ERROR_CHECK(err_code);
m_used |= USED_PWM(0);
m_demo1_seq_values.channel_0 = 33;
m_demo1_seq_values.channel_1 = 40;
m_demo1_seq_values.channel_2 = 50;
m_demo1_seq_values.channel_3 = 60;
m_demo1_phase = 0;
nrf_drv_pwm_simple_playback(&m_pwm0, &m_demo1_seq, 1,
NRF_DRV_PWM_FLAG_LOOP);
}
