| /* |
| * Copyright (c) 2016 Intel Corporation |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| |
| /** |
| * @file Sample app to demonstrate PWM. |
| * |
| * This app uses PWM[0]. |
| */ |
| |
| #include <zephyr.h> |
| #include <misc/printk.h> |
| #include <device.h> |
| #include <pwm.h> |
| |
| /* |
| * Unlike pulse width, period is not a critical parameter for |
| * motor control. 20ms is commonly used. |
| */ |
| #define PERIOD (USEC_PER_SEC / 50) |
| |
| /* all in micro second */ |
| #define STEPSIZE 100 |
| #define MINPULSEWIDTH 700 |
| #define MAXPULSEWIDTH 2300 |
| |
| void main(void) |
| { |
| struct device *pwm_dev; |
| uint32_t pulse_width = MINPULSEWIDTH; |
| uint8_t dir = 0; |
| |
| printk("PWM demo app-servo control\n"); |
| |
| pwm_dev = device_get_binding("PWM_0"); |
| if (!pwm_dev) { |
| printk("Cannot find PWM_0!\n"); |
| return; |
| } |
| |
| while (1) { |
| if (pwm_pin_set_usec(pwm_dev, 0, PERIOD, pulse_width)) { |
| printk("pwm pin set fails\n"); |
| return; |
| } |
| |
| if (dir) { |
| if (pulse_width <= MINPULSEWIDTH) { |
| dir = 0; |
| pulse_width = MINPULSEWIDTH; |
| } else { |
| pulse_width -= STEPSIZE; |
| } |
| } else { |
| pulse_width += STEPSIZE; |
| |
| if (pulse_width >= MAXPULSEWIDTH) { |
| dir = 1; |
| pulse_width = MAXPULSEWIDTH; |
| } |
| } |
| |
| k_sleep(MSEC_PER_SEC); |
| } |
| } |