c9c9c9797f
Extend automated testing on HW by veryfing console output. Signed-off-by: Piotr Kosycarz <piotr.kosycarz@nordicsemi.no>
81 lines
1.8 KiB
C
81 lines
1.8 KiB
C
/*
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* Copyright (c) 2016 Intel Corporation
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* Copyright (c) 2020 Nordic Semiconductor ASA
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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/**
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* @file Sample app to demonstrate PWM.
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*/
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#include <zephyr/kernel.h>
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#include <zephyr/sys/printk.h>
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#include <zephyr/device.h>
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#include <zephyr/drivers/pwm.h>
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static const struct pwm_dt_spec pwm_led0 = PWM_DT_SPEC_GET(DT_ALIAS(pwm_led0));
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#define MIN_PERIOD PWM_SEC(1U) / 128U
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#define MAX_PERIOD PWM_SEC(1U)
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int main(void)
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{
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uint32_t max_period;
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uint32_t period;
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uint8_t dir = 0U;
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int ret;
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printk("PWM-based blinky\n");
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if (!pwm_is_ready_dt(&pwm_led0)) {
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printk("Error: PWM device %s is not ready\n",
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pwm_led0.dev->name);
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return 0;
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}
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/*
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* In case the default MAX_PERIOD value cannot be set for
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* some PWM hardware, decrease its value until it can.
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*
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* Keep its value at least MIN_PERIOD * 4 to make sure
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* the sample changes frequency at least once.
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*/
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printk("Calibrating for channel %d...\n", pwm_led0.channel);
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max_period = MAX_PERIOD;
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while (pwm_set_dt(&pwm_led0, max_period, max_period / 2U)) {
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max_period /= 2U;
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if (max_period < (4U * MIN_PERIOD)) {
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printk("Error: PWM device "
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"does not support a period at least %lu\n",
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4U * MIN_PERIOD);
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return 0;
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}
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}
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printk("Done calibrating; maximum/minimum periods %u/%lu nsec\n",
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max_period, MIN_PERIOD);
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period = max_period;
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while (1) {
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ret = pwm_set_dt(&pwm_led0, period, period / 2U);
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if (ret) {
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printk("Error %d: failed to set pulse width\n", ret);
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return 0;
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}
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printk("Using period %d\n", period);
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period = dir ? (period * 2U) : (period / 2U);
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if (period > max_period) {
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period = max_period / 2U;
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dir = 0U;
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} else if (period < MIN_PERIOD) {
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period = MIN_PERIOD * 2U;
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dir = 1U;
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}
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k_sleep(K_SECONDS(4U));
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}
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return 0;
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}
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