1 /* esp_event (event loop library) basic example
2
3 This example code is in the Public Domain (or CC0 licensed, at your option.)
4
5 Unless required by applicable law or agreed to in writing, this
6 software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
7 CONDITIONS OF ANY KIND, either express or implied.
8 */
9
10 #include "esp_log.h"
11
12 #include "freertos/FreeRTOS.h"
13 #include "freertos/task.h"
14
15 #include "event_source.h"
16 #include "esp_event_base.h"
17
18 static const char* TAG = "user_event_loops";
19
20 // Event loops
21 esp_event_loop_handle_t loop_with_task;
22 esp_event_loop_handle_t loop_without_task;
23
application_task(void * args)24 static void application_task(void* args)
25 {
26 while(1) {
27 ESP_LOGI(TAG, "application_task: running application task");
28 esp_event_loop_run(loop_without_task, 100);
29 vTaskDelay(10);
30 }
31 }
32
33 /* Event source task related definitions */
34 ESP_EVENT_DEFINE_BASE(TASK_EVENTS);
35
36 TaskHandle_t g_task;
37
task_iteration_handler(void * handler_args,esp_event_base_t base,int32_t id,void * event_data)38 static void task_iteration_handler(void* handler_args, esp_event_base_t base, int32_t id, void* event_data)
39 {
40 // Two types of data can be passed in to the event handler: the handler specific data and the event-specific data.
41 //
42 // The handler specific data (handler_args) is a pointer to the original data, therefore, the user should ensure that
43 // the memory location it points to is still valid when the handler executes.
44 //
45 // The event-specific data (event_data) is a pointer to a deep copy of the original data, and is managed automatically.
46 int iteration = *((int*) event_data);
47
48 char* loop;
49
50 if (handler_args == loop_with_task) {
51 loop = "loop_with_task";
52 } else {
53 loop = "loop_without_task";
54 }
55
56 ESP_LOGI(TAG, "handling %s:%s from %s, iteration %d", base, "TASK_ITERATION_EVENT", loop, iteration);
57 }
58
task_event_source(void * args)59 static void task_event_source(void* args)
60 {
61 for(int iteration = 1; iteration <= TASK_ITERATIONS_COUNT; iteration++) {
62 esp_event_loop_handle_t loop_to_post_to;
63
64 if (iteration % 2 == 0) {
65 // if even, post to the event loop with dedicated task
66 loop_to_post_to = loop_with_task;
67 } else {
68 // if odd, post to the event loop without a dedicated task
69 loop_to_post_to = loop_without_task;
70 }
71
72 ESP_LOGI(TAG, "posting %s:%s to %s, iteration %d out of %d", TASK_EVENTS, "TASK_ITERATION_EVENT",
73 loop_to_post_to == loop_with_task ? "loop_with_task" : "loop_without_task",
74 iteration, TASK_ITERATIONS_COUNT);
75
76 ESP_ERROR_CHECK(esp_event_post_to(loop_to_post_to, TASK_EVENTS, TASK_ITERATION_EVENT, &iteration, sizeof(iteration), portMAX_DELAY));
77
78 vTaskDelay(pdMS_TO_TICKS(TASK_PERIOD));
79 }
80
81 vTaskDelay(pdMS_TO_TICKS(TASK_PERIOD));
82
83 ESP_LOGI(TAG, "deleting task event source");
84
85 vTaskDelete(NULL);
86 }
87
88 /* Example main */
app_main(void)89 void app_main(void)
90 {
91 ESP_LOGI(TAG, "setting up");
92
93 esp_event_loop_args_t loop_with_task_args = {
94 .queue_size = 5,
95 .task_name = "loop_task", // task will be created
96 .task_priority = uxTaskPriorityGet(NULL),
97 .task_stack_size = 2048,
98 .task_core_id = tskNO_AFFINITY
99 };
100
101 esp_event_loop_args_t loop_without_task_args = {
102 .queue_size = 5,
103 .task_name = NULL // no task will be created
104 };
105
106 // Create the event loops
107 ESP_ERROR_CHECK(esp_event_loop_create(&loop_with_task_args, &loop_with_task));
108 ESP_ERROR_CHECK(esp_event_loop_create(&loop_without_task_args, &loop_without_task));
109
110 // Register the handler for task iteration event. Notice that the same handler is used for handling event on different loops.
111 // The loop handle is provided as an argument in order for this example to display the loop the handler is being run on.
112 ESP_ERROR_CHECK(esp_event_handler_instance_register_with(loop_with_task, TASK_EVENTS, TASK_ITERATION_EVENT, task_iteration_handler, loop_with_task, NULL));
113 ESP_ERROR_CHECK(esp_event_handler_instance_register_with(loop_without_task, TASK_EVENTS, TASK_ITERATION_EVENT, task_iteration_handler, loop_without_task, NULL));
114
115 ESP_LOGI(TAG, "starting event source");
116
117 // Create the event source task with the same priority as the current task
118 xTaskCreate(task_event_source, "task_event_source", 2048, NULL, uxTaskPriorityGet(NULL), NULL);
119
120 ESP_LOGI(TAG, "starting application task");
121 // Create the application task with the same priority as the current task
122 xTaskCreate(application_task, "application_task", 2048, NULL, uxTaskPriorityGet(NULL), NULL);
123 }
124
