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 <math.h>
17 #include <stdio.h>
18 #include <string.h>
19 #include <unistd.h>
20
21 #include "cmsis_os2.h"
22 #include "iot_adc.h"
23 #include "iot_errno.h"
24 #include "iot_gpio_ex.h"
25 #include "ohos_init.h"
26
27 #define ADC_TASK_STACK_SIZE (1024 * 8)
28 #define ADC_TASK_PRIO 24
29 #define ADC_GPIO 11
30 #define ADC_CHANNEL 5
31 #define ADC_TASK_DELAY_1S 1000000
32
33 #define ADC_VREF_VOL 1.8
34 #define ADC_COEFFICIENT 4
35 #define ADC_RATIO 4096
36
37 /**
38 * @brief get ADC sampling value and convert it to voltage
39 *
40 */
GetVoltage(void)41 static float GetVoltage(void)
42 {
43 unsigned int ret;
44 unsigned short data;
45
46 ret = IoTAdcRead(ADC_CHANNEL, &data, IOT_ADC_EQU_MODEL_8, IOT_ADC_CUR_BAIS_DEFAULT, 0xff);
47 if (ret != IOT_SUCCESS) {
48 printf("ADC Read Fail\n");
49 }
50
51 return (float)data * ADC_VREF_VOL * ADC_COEFFICIENT / ADC_RATIO;
52 }
53
54 /**
55 * @brief Adc task get adc sampling voltage
56 *
57 */
AdcTask(void)58 static void AdcTask(void)
59 {
60 float voltage;
61
62 // set GPIO_11 to pull-up mode
63 IoTGpioSetPull(ADC_GPIO, IOT_GPIO_PULL_UP);
64 while (1) {
65 printf("=======================================\r\n");
66 printf("***************ADC_example*************\r\n");
67 printf("=======================================\r\n");
68
69 // get adc sampling voltage
70 voltage = GetVoltage();
71 printf("vlt:%.3fV\n", voltage);
72
73 // delay 1s
74 usleep(ADC_TASK_DELAY_1S);
75 }
76 }
77
78 /**
79 * @brief Main Entry of the Adc Example
80 *
81 */
AdcExampleEntry(void)82 static void AdcExampleEntry(void)
83 {
84 osThreadAttr_t attr;
85
86 attr.name = "AdcTask";
87 attr.attr_bits = 0U;
88 attr.cb_mem = NULL;
89 attr.cb_size = 0U;
90 attr.stack_mem = NULL;
91 attr.stack_size = ADC_TASK_STACK_SIZE;
92 attr.priority = ADC_TASK_PRIO;
93
94 if (osThreadNew((osThreadFunc_t)AdcTask, NULL, &attr) == NULL) {
95 printf("Failed to create AdcTask!\n");
96 }
97 }
98
99 APP_FEATURE_INIT(AdcExampleEntry);