ESP-NOW APIs. More...

Typedefs
typedef void(*	esp_now_recv_cb_t) (uint8 mac_addr, uint8 data, uint8 len)
	ESP-NOW send callback. More...

typedef void(*	esp_now_send_cb_t) (uint8 *mac_addr, uint8 status)
	ESP-NOW send callback. More...

Enumerations
enum	esp_now_role { ESP_NOW_ROLE_IDLE = 0, ESP_NOW_ROLE_CONTROLLER, ESP_NOW_ROLE_SLAVE, ESP_NOW_ROLE_MAX }

Functions
sint32	esp_now_init (void)
	ESP-NOW initialization. More...

sint32	esp_now_deinit (void)
	Deinitialize ESP-NOW. More...

sint32	esp_now_register_send_cb (esp_now_send_cb_t cb)
	Register ESP-NOW send callback. More...

sint32	esp_now_unregister_send_cb (void)
	Unregister ESP-NOW send callback. More...

sint32	esp_now_register_recv_cb (esp_now_recv_cb_t cb)
	Register ESP-NOW receive callback. More...

sint32	esp_now_unregister_recv_cb (void)
	Unregister ESP-NOW receive callback. More...

sint32	esp_now_send (uint8 da, uint8 data, uint8 len)
	Send ESP-NOW packet. More...

sint32	esp_now_add_peer (uint8 mac_addr, uint8 role, uint8 channel, uint8 key, uint8 key_len)
	Add an ESP-NOW peer, store MAC address of target device into ESP-NOW MAC list. More...

sint32	esp_now_del_peer (uint8 *mac_addr)
	Delete an ESP-NOW peer, delete MAC address of the device from ESP-NOW MAC list. More...

sint32	esp_now_set_self_role (uint8 role)
	Set ESP-NOW role of device itself. More...

sint32	esp_now_get_self_role (void)
	Get ESP-NOW role of device itself. More...

sint32	esp_now_set_peer_role (uint8 *mac_addr, uint8 role)
	Set ESP-NOW role for a target device. If it is set multiple times, new role will cover the old one. More...

sint32	esp_now_get_peer_role (uint8 *mac_addr)
	Get ESP-NOW role of a target device. More...

sint32	esp_now_set_peer_channel (uint8 *mac_addr, uint8 channel)
	Record channel information of a ESP-NOW device. More...

sint32	esp_now_get_peer_channel (uint8 *mac_addr)
	Get channel information of a ESP-NOW device. More...

sint32	esp_now_set_peer_key (uint8 mac_addr, uint8 key, uint8 key_len)
	Set ESP-NOW key for a target device. More...

sint32	esp_now_get_peer_key (uint8 mac_addr, uint8 key, uint8 *key_len)
	Get ESP-NOW key of a target device. More...

uint8 *	esp_now_fetch_peer (bool restart)
	Get MAC address of ESP-NOW device. More...

sint32	esp_now_is_peer_exist (uint8 *mac_addr)
	Check if target device exists or not. More...

sint32	esp_now_get_cnt_info (uint8 all_cnt, uint8 encrypt_cnt)
	Get the total number of ESP-NOW devices which are associated, and the number count of encrypted devices. More...

sint32	esp_now_set_kok (uint8 *key, uint8 len)
	Set the encrypt key of communication key. More...

Detailed Description

ESP-NOW APIs.

Attention: 1. ESP-NOW do not support broadcast and multicast.; 2. ESP-NOW is targeted to Smart-Light project, so it is suggested that slave role corresponding to soft-AP or soft-AP+station mode, controller role corresponding to station mode.; 3. When ESP8266 is in soft-AP+station mode, it will communicate through station interface if it is in slave role, and communicate through soft-AP interface if it is in controller role.; 4. ESP-NOW can not wake ESP8266 up from sleep, so if the target ESP8266 station is in sleep, ESP-NOW communication will fail.; 5. In station mode, ESP8266 supports 10 encrypt ESP-NOW peers at most, with the unencrypted peers, it can be 20 peers in total at most.; 6. In the soft-AP mode or soft-AP + station mode, the ESP8266 supports 6 encrypt ESP-NOW peers at most, with the unencrypted peers, it can be 20 peers in total at most.

Typedef Documentation

typedef void(* esp_now_recv_cb_t) (uint8 *mac_addr, uint8 *data, uint8 len)

ESP-NOW send callback.

Attention: The status will be OK, if ESP-NOW send packet successfully. But users need to make sure by themselves that key of communication is correct.

Parameters

uint8	*mac_addr : MAC address of target device
uint8	*data : data received
uint8	len : data length

Returns: null

typedef void(* esp_now_send_cb_t) (uint8 *mac_addr, uint8 status)

ESP-NOW send callback.

Attention: The status will be OK, if ESP-NOW send packet successfully. But users need to make sure by themselves that key of communication is correct.

Parameters

uint8	*mac_addr : MAC address of target device
uint8	status : status of ESP-NOW sending packet, 0, OK; 1, fail.

Returns: null

Function Documentation

sint32 esp_now_add_peer	(	uint8 *	mac_addr,
		uint8	role,
		uint8	channel,
		uint8 *	key,
		uint8	key_len
	)

Add an ESP-NOW peer, store MAC address of target device into ESP-NOW MAC list.

Parameters

uint8	*mac_addr : MAC address of device
uint8	role : role type of device, enum esp_now_role
uint8	channel : channel of device
uint8	*key : 16 bytes key which is needed for ESP-NOW communication
uint8	key_len : length of key, has to be 16 bytes now

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_deinit ( void )

Deinitialize ESP-NOW.

Parameters

null

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_del_peer ( uint8 * mac_addr )

Delete an ESP-NOW peer, delete MAC address of the device from ESP-NOW MAC list.

Parameters

u8	*mac_addr : MAC address of device

Returns: 0 : succeed; Non-0 : fail

uint8* esp_now_fetch_peer ( bool restart )

Get MAC address of ESP-NOW device.

Get MAC address of ESP-NOW device which is pointed now, and move the pointer to next one in ESP-NOW MAC list or move the pointer to the first one in ESP-NOW MAC list.

Attention: 1. This API can not re-entry; 2. Parameter has to be true when you call it the first time.

Parameters

bool	restart : true, move pointer to the first one in ESP-NOW MAC list; false, move pointer to the next one in ESP-NOW MAC list

Returns: NULL, no ESP-NOW devices exist; Otherwise, MAC address of ESP-NOW device which is pointed now

sint32 esp_now_get_cnt_info	(	uint8 *	all_cnt,
		uint8 *	encrypt_cnt
	)

Get the total number of ESP-NOW devices which are associated, and the number count of encrypted devices.

Parameters

uint8	*all_cnt : total number of ESP-NOW devices which are associated.
uint8	*encryp_cnt : number count of encrypted devices

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_get_peer_channel ( uint8 * mac_addr )

Get channel information of a ESP-NOW device.

Attention: ESP-NOW communication needs to be at the same channel.

Parameters

uint8 *mac_addr : MAC address of target device.

Returns: 1 ~ 13 (some area may get 14) : channel number; Non-0 : fail

sint32 esp_now_get_peer_key	(	uint8 *	mac_addr,
		uint8 *	key,
		uint8 *	key_len
	)

Get ESP-NOW key of a target device.

If it is set multiple times, new key will cover the old one.

Parameters

uint8	*mac_addr : MAC address of target device.
uint8	*key : pointer of key, buffer size has to be 16 bytes at least
uint8	key_len : key length

Returns: 0 : succeed; > 0 : find target device but can't get key; < 0 : fail

sint32 esp_now_get_peer_role ( uint8 * mac_addr )

Get ESP-NOW role of a target device.

Parameters

uint8 *mac_addr : MAC address of device.

Returns: ESP_NOW_ROLE_CONTROLLER, role type : controller; ESP_NOW_ROLE_SLAVE, role type : slave; otherwise : fail

sint32 esp_now_get_self_role ( void )

Get ESP-NOW role of device itself.

Parameters

uint8 role : role type of device, enum esp_now_role.

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_init ( void )

ESP-NOW initialization.

Parameters

null

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_is_peer_exist ( uint8 * mac_addr )

Check if target device exists or not.

Parameters

uint8 *mac_addr : MAC address of target device.

Returns: 0 : device does not exist; < 0 : error occur, check fail; > 0 : device exists

sint32 esp_now_register_recv_cb ( esp_now_recv_cb_t cb )

Register ESP-NOW receive callback.

Parameters

esp_now_recv_cb_t cb : receive callback

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_register_send_cb ( esp_now_send_cb_t cb )

Register ESP-NOW send callback.

Parameters

esp_now_send_cb_t cb : send callback

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_send	(	uint8 *	da,
		uint8 *	data,
		uint8	len
	)

Send ESP-NOW packet.

Parameters

uint8	*da : destination MAC address. If it's NULL, send packet to all MAC addresses recorded by ESP-NOW; otherwise, send packet to target MAC address.
uint8	*data : data need to send
uint8	len : data length

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_set_kok	(	uint8 *	key,
		uint8	len
	)

Set the encrypt key of communication key.

All ESP-NOW devices share the same encrypt key. If users do not set the encrypt key, ESP-NOW communication key will be encrypted by a default key.

Parameters

uint8	*key : pointer of encrypt key.
uint8	len : key length, has to be 16 bytes now.

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_set_peer_channel	(	uint8 *	mac_addr,
		uint8	channel
	)

Record channel information of a ESP-NOW device.

When communicate with this device,

call esp_now_get_peer_channel to get its channel first,
then call wifi_set_channel to be in the same channel and do communication.

Parameters

uint8	*mac_addr : MAC address of target device.
uint8	channel : channel, usually to be 1 ~ 13, some area may use channel 14.

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_set_peer_key	(	uint8 *	mac_addr,
		uint8 *	key,
		uint8	key_len
	)

Set ESP-NOW key for a target device.

If it is set multiple times, new key will cover the old one.

Parameters

uint8	*mac_addr : MAC address of target device.
uint8	*key : 16 bytes key which is needed for ESP-NOW communication, if it is NULL, current key will be reset to be none.
uint8	key_len : key length, has to be 16 bytes now

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_set_peer_role	(	uint8 *	mac_addr,
		uint8	role
	)

Set ESP-NOW role for a target device. If it is set multiple times, new role will cover the old one.

Parameters

uint8	*mac_addr : MAC address of device.
uint8	role : role type, enum esp_now_role.

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_set_self_role ( uint8 role )

Set ESP-NOW role of device itself.

Parameters

uint8 role : role type of device, enum esp_now_role.

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_unregister_recv_cb ( void )

Unregister ESP-NOW receive callback.

Parameters

null

Returns: 0 : succeed; Non-0 : fail

sint32 esp_now_unregister_send_cb ( void )

Unregister ESP-NOW send callback.

Parameters

null

Returns: 0 : succeed; Non-0 : fail

Typedefs

Enumerations

Functions

Detailed Description

Typedef Documentation

Function Documentation