1 /*
2 * Copyright (c) 2020 Nanjing Xiaoxiongpai Intelligent Technology Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16 #include <stdio.h>
17
18 #include <unistd.h>
19
20 #include "cmsis_os2.h"
21 #include "iot_gpio.h"
22 #include "iot_gpio_ex.h"
23 #include "iot_pwm.h"
24 #include "ohos_init.h"
25
26 #define LED_GPIO 2
27 #define THREAD_STACK_SIZE (1024 * 4)
28 #define THREAD_PRIO 25
29
30 #define PWM_CHANGE_TIMES 100
31 #define PWM_FREQ 40000
32 #define PWM_DELAY_10US 10
33
34 /**
35 * @brief pwm task output PWM with different duty cycle
36 *
37 */
PwmTask(void)38 static void PwmTask(void)
39 {
40 unsigned int i;
41
42 // init gpio of LED
43 IoTGpioInit(LED_GPIO);
44
45 // set the GPIO_2 multiplexing function to PWM
46 IoTGpioSetFunc(LED_GPIO, IOT_GPIO_FUNC_GPIO_2_PWM2_OUT);
47
48 // set GPIO_2 is output mode
49 IoTGpioSetDir(LED_GPIO, IOT_GPIO_DIR_OUT);
50
51 // init PWM2
52 IoTPwmInit(LED_GPIO);
53
54 while (1) {
55 for (i = 0; i < PWM_CHANGE_TIMES; i++) {
56 // output PWM with different duty cycle
57 IoTPwmStart(LED_GPIO, i, PWM_FREQ);
58 usleep(PWM_DELAY_10US);
59 }
60 i = 0;
61 }
62 }
63
64 /**
65 * @brief Main Entry of the Pwm Example
66 *
67 */
PwmExampleEntry(void)68 static void PwmExampleEntry(void)
69 {
70 osThreadAttr_t attr;
71
72 attr.name = "PwmTask";
73 attr.attr_bits = 0U;
74 attr.cb_mem = NULL;
75 attr.cb_size = 0U;
76 attr.stack_mem = NULL;
77 attr.stack_size = THREAD_STACK_SIZE;
78 attr.priority = THREAD_PRIO;
79
80 if (osThreadNew((osThreadFunc_t)PwmTask, NULL, &attr) == NULL) {
81 printf("Failed to create PwmTask!\n");
82 }
83 }
84
85 APP_FEATURE_INIT(PwmExampleEntry);