esp_now_send() function

Send ESPNOW data @attention 1. If peer_addr is not NULL, send data to the peer whose MAC address matches peer_addr @attention 2. If peer_addr is NULL, send data to all of the peers that are added to the peer list @attention 3. The maximum length of data must be less than ESP_NOW_MAX_DATA_LEN @attention 4. The buffer pointed to by data argument does not need to be valid after esp_now_send returns

Syntax

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Summary

Declaration

from esp_now.h:213

esp_err_t esp_now_send(const uint8_t *peer_addr, const uint8_t *data, size_t len);

Arguments

Argument

Declared as

Description

peer_addr

const uint8_t *

peer MAC address

data

const uint8_t *

data to send

len

size_t

length of data

Return value

- ESP_OK : succeed - ESP_ERR_ESPNOW_NOT_INIT : ESPNOW is not initialized - ESP_ERR_ESPNOW_ARG : invalid argument - ESP_ERR_ESPNOW_INTERNAL : internal error - ESP_ERR_ESPNOW_NO_MEM : out of memory, when this happens, you can delay a while before sending the next data - ESP_ERR_ESPNOW_NOT_FOUND : peer is not found - ESP_ERR_ESPNOW_IF : current Wi-Fi interface doesn't match that of peer - ESP_ERR_ESPNOW_CHAN: current Wi-Fi channel doesn't match that of peer

Examples

esp_now_send() is referenced by 1 libraries and example projects:

espnow sample

References

from 0/1 examples

Code

Location

esp_err_t esp_now_send(const uint8_t *peer_addr, const uint8_t *data, size_t len);

esp_now.h:213

esp_now_send() function

Syntax

Arguments

Return value

Examples

References

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