ESP Peripherals

This library simplifies the management of peripherals, by pooling and monitoring in a single task, adding basic functions to send and receive events. And it also provides APIs to easily integrate new peripherals.

Note

Note that if you do not intend to integrate new peripherals into esp_peripherals, you are only interested in simple api esp_periph_init, esp_periph_start, esp_periph_stop and esp_periph_destroy. If you want to integrate new peripherals, please refer to Periph Button source code

Examples

Please refer to player/pipeline_http_mp3/main/play_http_mp3_example.c.

API Reference

Header File

Functions

esp_periph_set_handle_t esp_periph_set_init(esp_periph_config_t *config)

Initialize esp_peripheral sets, create empty peripherals list. Call this function before starting any peripherals (with esp_periph_start). This call will initialize the data needed for esp_peripherals to work, but does not actually create the task. The event_handle is optional if you want to receive events from this callback function. The esp_peripherals task will send all events out to event_iface, can be listen by event_iface by esp_periph_get_event_iface. The user_context will sent esp_periph_event_handle_t as *context parameter.

Parameters

config – [in] The configurations

Returns

The peripheral sets instance

esp_err_t esp_periph_set_destroy(esp_periph_set_handle_t periph_set_handle)

This function will stop and kill the monitor task, calling all destroy callback functions of the peripheral (so you do not need to destroy the peripheral object manually). It will also remove all memory allocated to the peripherals list, so you need to call the esp_periph_set_init function again if you want to use it.

Parameters

periph_set_handle – The esp_periph_set_handle_t instance

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_set_stop_all(esp_periph_set_handle_t periph_set_handle)

Stop monitoring all peripherals, the peripheral state is still kept. This funciton only temporary disables the peripheral.

Parameters

periph_set_handle – The esp_periph_set_handle_t instance

Returns

  • ESP_OK

  • ESP_FAIL

esp_periph_handle_t esp_periph_set_get_by_id(esp_periph_set_handle_t periph_set_handle, int periph_id)

Get the peripheral handle by Peripheral ID.

Parameters

  • periph_set_handle – The esp_periph_set_handle_t instance

  • periph_id – [in] as esp_periph_id_t, or any ID you use when calling esp_periph_create

Returns

The esp_periph_handle_t

audio_event_iface_handle_t esp_periph_set_get_event_iface(esp_periph_set_handle_t periph_set_handle)

Return the event_iface used by this esp_peripherals.

Parameters

periph_set_handle – The esp_periph_set_handle_t instance

Returns

The audio event iface handle

esp_err_t esp_periph_set_register_callback(esp_periph_set_handle_t periph_set_handle, esp_periph_event_handle_t cb, void *user_context)

Register peripheral sets event callback function.

Parameters

  • periph_set_handle – The esp_periph_set_handle_t instance

  • cb – The event handle callback function

  • user_context – The user context pointer

Returns

  • ESP_OK

  • ESP_FAIL

QueueHandle_t esp_periph_set_get_queue(esp_periph_set_handle_t periph_set_handle)

Peripheral is using event_iface to control the event, all events are send out to event_iface queue. This function will be useful in case we want to read events directly from the event_iface queue.

Parameters

periph_set_handle – The esp_periph_set_handle_t instance

Returns

The queue handle

esp_err_t esp_periph_set_list_init(esp_periph_set_handle_t periph_set_handle)

Call this function to initialize all the listed peripherals.

Note

Work with no task peripheral set only

Parameters

periph_set_handle – The esp_periph_set_handle_t instance

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_set_list_run(esp_periph_set_handle_t periph_set_handle, audio_event_iface_msg_t msg)

Call this function to run all the listed peripherals.

Note

Work with no task peripheral set only

Parameters
Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_set_list_destroy(esp_periph_set_handle_t periph_set_handle)

Call this function to destroy all the listed peripherals.

Note

Work with no task peripheral set only

Parameters

periph_set_handle – The esp_periph_set_handle_t instance

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_remove_from_set(esp_periph_set_handle_t periph_set_handle, esp_periph_handle_t periph)

Call this function to remove periph from periph_set.

Parameters

  • periph_set_handle – The esp_periph_set_handle_t instance

  • periph – The esp_periph_handle_t instance

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_alloc_periph_id(esp_periph_set_handle_t periph_set_handle, int *periph_id)

Allocated a peripheral ID from the periph_set.

Note

This function can apply for a peripheral ID to realize a customized peripheral module. The requested peripheral ID will not be included in esp_periph_id_t

Parameters

  • periph_set_handle – [in] The esp_periph_set_handle_t instance

  • periph_id – [out] The peripheral identifier

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_set_change_waiting_time(esp_periph_set_handle_t periph_set_handle, int time_ms)

Call this function to change periph_set waiting time.

Parameters

  • periph_set_handle – The esp_periph_set_handle_t instance

  • time_ms – The waiting time

Returns

  • ESP_OK

  • ESP_FAIL

esp_periph_handle_t esp_periph_create(int periph_id, const char *tag)

Call this function to initialize a new peripheral.

Parameters

  • periph_id – [in] The periph identifier

  • tag – [in] The tag name, we named it easy to get in debug logs

Returns

The peripheral handle

esp_err_t esp_periph_set_function(esp_periph_handle_t periph, esp_periph_func init, esp_periph_run_func run, esp_periph_func destroy)

Each peripheral has a cycle of sequential operations from initialization, execution of commands to destroying the peripheral. These operations are represented by functions passed as call parameters to this function.

Parameters

  • periph – [in] The periph

  • init – [in] The initialize

  • run – [in] The run

  • destroy – [in] The destroy

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_start(esp_periph_set_handle_t periph_set_handle, esp_periph_handle_t periph)

Add the peripheral to peripherals list, enable and start monitor task (if task stack size > 0)

Note

This peripheral must be first created by calling esp_periph_create

Parameters

  • periph_set_handle – [in] The esp_periph_set_handle_t instance

  • periph – [in] The peripheral instance

Returns

  • ESP_OK on success

  • ESP_FAIL when any errors

esp_err_t esp_periph_stop(esp_periph_handle_t periph)

Stop monitoring the peripheral, the peripheral state is still kept. This funciton only temporary disables the peripheral.

Parameters

periph – [in] The periph

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_send_cmd(esp_periph_handle_t periph, int cmd, void *data, int data_len)

When this function is called, the command is passed to the event_iface command queue, and the esp_periph_run_func of this peripheral will be executed in the main peripheral task. This function can be called from any task, basically it only sends a queue to the main peripheral task.

Parameters

  • periph – [in] The periph

  • cmd – [in] The command

  • data – The data

  • data_len – [in] The data length

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_send_cmd_from_isr(esp_periph_handle_t periph, int cmd, void *data, int data_len)

Similar to esp_periph_send_cmd, but it can be called in the hardware interrupt handle.

Parameters

  • periph – [in] The periph

  • cmd – [in] The command

  • data – The data

  • data_len – [in] The data length

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_send_event(esp_periph_handle_t periph, int event_id, void *data, int data_len)

In addition to sending an event via event_iface, this function will dispatch the event_handle callback if the event_handle callback is provided at esp_periph_init

Parameters

  • periph – [in] The peripheral

  • event_id – [in] The event identifier

  • data – The data

  • data_len – [in] The data length

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_start_timer(esp_periph_handle_t periph, TickType_t interval_tick, timer_callback callback)

Each peripheral can initialize a timer, which is by default NULL. When this function is called, the timer for the peripheral is created and it invokes the callback function every interval tick.

Note

  • You do not need to stop or destroy the timer, when the esp_periph_destroy function is called, it will stop and destroy all

  • This timer using FreeRTOS Timer, with autoreload = true

Parameters

  • periph – [in] The peripheral

  • interval_tick – [in] The interval tick

  • callback – [in] The callback

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_stop_timer(esp_periph_handle_t periph)

Stop peripheral timer.

Parameters

periph – [in] The peripheral

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_set_data(esp_periph_handle_t periph, void *data)

Set the user data.

Note

Make sure the data lifetime is sufficient, this function does not copy all data, it only stores the data pointer

Parameters

  • periph – [in] The peripheral

  • data – The data

Returns

  • ESP_OK

  • ESP_FAIL

void *esp_periph_get_data(esp_periph_handle_t periph)

Get the user data stored in the peripheral.

Parameters

periph – [in] The peripheral

Returns

Peripheral data pointer

esp_periph_state_t esp_periph_get_state(esp_periph_handle_t periph)

Get the current state of peripheral.

Parameters

periph – [in] The handle of peripheral

Returns

The peripharal working state

esp_periph_id_t esp_periph_get_id(esp_periph_handle_t periph)

Get Peripheral identifier.

Parameters

periph – [in] The peripheral

Returns

The peripheral identifier

esp_err_t esp_periph_set_id(esp_periph_handle_t periph, esp_periph_id_t periph_id)

Set Peripheral identifier.

Parameters

  • periph – [in] The peripheral

  • periph_id – [in] The peripheral identifier

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_init(esp_periph_handle_t periph)

Call this to execute init function of peripheral instance.

Parameters

periph – The peripheral handle

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_run(esp_periph_handle_t periph)

Call this to execute run function of peripheral instance.

Parameters

periph – The peripheral handle

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_destroy(esp_periph_handle_t periph)

Call this to execute destroy function of peripheral instance.

Parameters

periph – The peripheral handle

Returns

  • ESP_OK

  • ESP_FAIL

esp_err_t esp_periph_register_on_events(esp_periph_handle_t periph, esp_periph_event_t *evts)

Rigster peripheral on event handle.

Parameters

  • periph – The peripheral handle

  • evts – The esp_periph_event_t handle

Returns

  • ESP_OK

  • ESP_FAIL

Structures

struct esp_periph_config_t

Common peripherals configurations.

Public Members

int task_stack

>0 Service task stack size; =0 without task created

int task_prio

Service task priority (based on freeRTOS priority)

int task_core

Service task running in core (0 or 1)

bool extern_stack

Service task stack allocate on extern ram

struct esp_periph_event

peripheral events

Public Members

void *user_ctx

peripheral context data

esp_periph_event_handle_t cb

peripheral callback function

audio_event_iface_handle_t iface

peripheral event

Macros

DEFAULT_ESP_PERIPH_STACK_SIZE
DEFAULT_ESP_PERIPH_TASK_PRIO
DEFAULT_ESP_PERIPH_TASK_CORE
DEFAULT_ESP_PERIPH_SET_CONFIG()
periph_tick_get

Type Definitions

typedef struct esp_periph_sets *esp_periph_set_handle_t
typedef struct esp_periph *esp_periph_handle_t
typedef esp_err_t (*esp_periph_func)(esp_periph_handle_t periph)
typedef esp_err_t (*esp_periph_run_func)(esp_periph_handle_t periph, audio_event_iface_msg_t *msg)
typedef esp_err_t (*esp_periph_event_handle_t)(audio_event_iface_msg_t *event, void *context)
typedef void (*timer_callback)(xTimerHandle tmr)
typedef struct esp_periph_event esp_periph_event_t

peripheral events

Enumerations

enum esp_periph_id_t

Peripheral Identify, this must be unique for each peripheral added to the peripherals list.

Values:

enumerator PERIPH_ID_BUTTON
enumerator PERIPH_ID_TOUCH
enumerator PERIPH_ID_SDCARD
enumerator PERIPH_ID_WIFI
enumerator PERIPH_ID_FLASH
enumerator PERIPH_ID_AUXIN
enumerator PERIPH_ID_ADC
enumerator PERIPH_ID_CONSOLE
enumerator PERIPH_ID_BLUETOOTH
enumerator PERIPH_ID_LED
enumerator PERIPH_ID_SPIFFS
enumerator PERIPH_ID_ADC_BTN
enumerator PERIPH_ID_IS31FL3216
enumerator PERIPH_ID_GPIO_ISR
enumerator PERIPH_ID_WS2812
enumerator PERIPH_ID_AW2013
enumerator PERIPH_ID_LCD
enumerator PERIPH_ID_CUSTOM_BASE
enum esp_periph_state_t

Peripheral working state.

Values:

enumerator PERIPH_STATE_NULL
enumerator PERIPH_STATE_INIT
enumerator PERIPH_STATE_RUNNING
enumerator PERIPH_STATE_PAUSE
enumerator PERIPH_STATE_STOPPING
enumerator PERIPH_STATE_ERROR
enumerator PERIPH_STATE_STATUS_MAX

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