Espressif ESP32-S2 User Manual

Chapter 2. API Reference
• ESP_OK: succeed
• ESP_ERR_WIFI_NOT_INIT: WiFi is not initialized by esp_wifi_init
• ESP_ERR_WIFI_NOT_STARTED: WiFi was not started by esp_wifi_start
• ESP_ERR_WIFI_TIMEOUT: blocking scan is timeout
• ESP_ERR_WIFI_STATE: wifi still connecting when invoke esp_wifi_scan_start
• others: refer to error code in esp_err.h
Parameters
• config: configuration of scanning
• block: if block is true, this API will block the caller until the scan is done, otherwise it will return
immediately
esp_err_t esp_wifi_scan_stop(void)
Stop the scan in process.
Return
• ESP_OK: succeed
• ESP_ERR_WIFI_NOT_INIT: WiFi is not initialized by esp_wifi_init
• ESP_ERR_WIFI_NOT_STARTED: WiFi is not started by esp_wifi_start
esp_err_t esp_wifi_scan_get_ap_num(uint16_t *number)
Get number of APs found in last scan.
Attention This API can only be called when the scan is completed, otherwise it may get wrong value.
Return
• ESP_OK: succeed
• ESP_ERR_WIFI_NOT_INIT: WiFi is not initialized by esp_wifi_init
• ESP_ERR_WIFI_NOT_STARTED: WiFi is not started by esp_wifi_start
• ESP_ERR_INVALID_ARG: invalid argument
Parameters
• [out] number: store number of APIs found in last scan
esp_err_t esp_wifi_scan_get_ap_records(uint16_t *number, wifi_ap_record_t *ap_records)
Get AP list found in last scan.
Return
• ESP_OK: succeed
• ESP_ERR_WIFI_NOT_INIT: WiFi is not initialized by esp_wifi_init
• ESP_ERR_WIFI_NOT_STARTED: WiFi is not started by esp_wifi_start
• ESP_ERR_INVALID_ARG: invalid argument
• ESP_ERR_NO_MEM: out of memory
Parameters
• [inout] number: As input param, it stores max AP number ap_records can hold. As output
param, it receives the actual AP number this API returns.
• ap_records: wifi_ap_record_t array to hold the found APs
esp_err_t esp_wifi_sta_get_ap_info(wifi_ap_record_t *ap_info)
Get information of AP which the ESP32 station is associated with.
Attention When the obtained country information is empty, it means that the AP does not carry country
information
Return
• ESP_OK: succeed
• ESP_ERR_WIFI_CONN: The station interface don’t initialized
• ESP_ERR_WIFI_NOT_CONNECT: The station is in disconnect status
Parameters
• ap_info: the wifi_ap_record_t to hold AP information sta can get the connected ap’s phy mode
info through the struct member phy_11b，phy_11g，phy_11n，phy_lr in the wifi_ap_record_t struct.
For example, phy_11b = 1 imply that ap support 802.11b mode
esp_err_t esp_wifi_set_ps(wifi_ps_type_t type)
Set current WiFi power save type.
Attention Default power save type is WIFI_PS_MIN_MODEM.
Espressif Systems 90
Submit Document Feedback
Release v4.4

Espressif ESP32-S2 Specifications

General

Brand	Espressif
Model	ESP32-S2
Category	Single board computers
Language	English