1 /*
2 * Copyright (c) 2023 Ian Morris
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <stdio.h>
8 #include <stdlib.h>
9
10 #include <zephyr/device.h>
11 #include <zephyr/drivers/sensor.h>
12 #include <zephyr/sys/util_macro.h>
13 #include <zephyr/kernel.h>
14
15 #define DHT_ALIAS(i) DT_ALIAS(_CONCAT(dht, i))
16 #define DHT_DEVICE(i, _) \
17 IF_ENABLED(DT_NODE_EXISTS(DHT_ALIAS(i)), (DEVICE_DT_GET(DHT_ALIAS(i)),))
18
19 /* Support up to 10 temperature/humidity sensors */
20 static const struct device *const sensors[] = {LISTIFY(10, DHT_DEVICE, ())};
21
main(void)22 int main(void)
23 {
24 int rc;
25
26 for (size_t i = 0; i < ARRAY_SIZE(sensors); i++) {
27 if (!device_is_ready(sensors[i])) {
28 printk("sensor: device %s not ready.\n", sensors[i]->name);
29 return 0;
30 }
31 }
32
33 while (1) {
34 for (size_t i = 0; i < ARRAY_SIZE(sensors); i++) {
35 struct device *dev = (struct device *)sensors[i];
36
37 rc = sensor_sample_fetch(dev);
38 if (rc < 0) {
39 printk("%s: sensor_sample_fetch() failed: %d\n", dev->name, rc);
40 return rc;
41 }
42
43 struct sensor_value temp;
44 struct sensor_value hum;
45
46 rc = sensor_channel_get(dev, SENSOR_CHAN_AMBIENT_TEMP, &temp);
47 if (rc == 0) {
48 rc = sensor_channel_get(dev, SENSOR_CHAN_HUMIDITY, &hum);
49 }
50 if (rc != 0) {
51 printf("get failed: %d\n", rc);
52 break;
53 }
54
55 printk("%16s: temp is %d.%02d °C humidity is %d.%02d %%RH\n",
56 dev->name, temp.val1, temp.val2 / 10000,
57 hum.val1, hum.val2 / 10000);
58 }
59 k_msleep(1000);
60 }
61 return 0;
62 }
63
