v4.1.0.0 Release Notes

v4.1.0.0 is released for ESP32-C2, ESP32-C3, ESP32-C6, and ESP32. The changes since the previous version are as follows.

• ESP32C2-AT
• ESP32C3-AT
• ESP32C6-AT
• ESP32-AT

ESP32C2-AT

Documentation for Release v4.1.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v4.1.0.0/esp32c2/index.html. ESP32C2-AT v4.1.0.0 is a major update for ESP32C2-AT v3.3.0.0.

The firmware:

• ESP32-C2-4MB-G2-AT-V4.1.0.0.zip
• ESP32-C2-4MB-AT-V4.1.0.0.zip
• ESP32-C2-2MB-AT-V4.1.0.0.zip

This is the list of changes since release v3.3.0.0:

Known Issues

• AT+FS may fail after repeated read/write operations

Changelog

Basic

• Added the AT+SYSRAM setup command to detail memory capacity
• Added the AT+SYSROLLBACK query command to obtain the address and version of the current and rollback firmware
• Added the AT+RFCAL command to support RF full calibration
• Added deduplication support for the AT+SYSMFG command
• Added sleep support in the BLE‑only firmware
• Added support to disable sleep when Wi‑Fi and BLE coexist
• Fixed an issue where AT+SYSMSGFILTER did not work when the data contained \r\n

Wi-Fi

• Added the AT+CWBANDWIDTH command to set Wi‑Fi bandwidth
• Added the AT+CWCONFIG command to set the global inactive time and listen interval
• Expand authmode range for AT+CWLAPOPT, AT+WPS, AT+CWSTARTSMART and AT+BLUFI
• Fixed a station‑connection failure when using AT+CWJAP after connecting to an Enterprise AP with AT+CWJEAP
• Fixed a crash when setting hostname length to 32 bytes via AT+CWHOSTNAME
• Fixed two WPA2‑Enterprise connection issues
• Fixed a potential Wi‑Fi issue where the device disconnected immediately after powering on and connecting to the AP
• Fixed an issue where AT+CWLAP did not return valid APs when BLUFI was enabled
• Fixed incorrect Wi‑Fi reconnection behavior after sending the AT+CWQAP and AT+CWRECONNCFG commands
• Fixed a Wi‑Fi disconnection issue when sending the AT+CWRECONNCFG command twice
• Fixed an issue where IPv6 information was output in passthrough mode

TCP/IP

• Added a netif parameter to the AT+CIPSERVER command
• Added the AT+CIPSSLCCIPHER command to configure the SSL cipher‑suite list
• Added a timeout parameter to the AT+CIPSTART and AT+CIPDOMAIN commands
• Added support for a backup DNS server in AT+CIPDNS in AT+CIPDNS
• Fixed AT+CWDHCP returning an incorrect DHCP state after the DHCP server was disabled
• Fixed an issue where AT+CIPRECVLEN? always returned a fixed set of five connections
• Fixed several issues where AT+CIPSTATUS returned incorrect statuses
• Fixed an infinite‑loop issue when the SSL server encountered a PKI read error
• Fixed some potential reconnection issues in passthrough mode
• Fixed an issue where TLS resources were not freed if TLS negotiation failed
• Fixed an issue where AT+CIPCLOSE could not close a connection after reaching the maximum number of open sockets
• Fixed an issue where the UDP mode in AT+CIPSTART did not work in passive‑read mode
• Fixed an asynchronous issue with AT+CIPRECVLEN
• Fixed an issue where AT+CIPSTO did not take effect when data transmission failed

mDNS

• Added mDNS query support to AT+MDNS
• Added the instance, proto, and txt parameters to the AT+MDNS command

HTTP

• Enabled HTTP commands on the esp32c2‑2mb firmware
• Added HTTP status‑code output for HTTP commands
• Added the AT+HTTPCFG command to configure certificates for HTTP
• Added HTTP‑header deduplication to the AT+HTTPCHEAD command

MQTT

• Change MQTT message retransmission interval from 1 second to 5 seconds to improve connection stability
• Fixed a potential issue where MQTT subscribe via AT+MQTTSUB failed but returned OK
• Fixed an issue where an MQTT QoS 2 PUBREL packet might not be retransmitted

FatFS

• Added FatFS support on 2 MB flash
• Added a data‑length check when writing to FatFS
• Fixed several FatFS mount and unmount issues
• Fixed a mismatch between the generated fatfs.bin size and the required size
• Fixed an issue where FatFS did not work if fatfs.bin was not pre‑burned before flashing
• Fixed an issue where fwrite() returned OK but data was not written to the file system

OTA

• Enabled app rollback support
• Added compressed OTA v3 support and a sanity checker

WebServer

• Fixed a compilation error when WebSocket and info logging were enabled
• Fixed two slist issues where the pointer fail_item was used after free
• Fixed a potential crash when printing if the SSID length was 32 bytes
• Fixed an issue where AT‑Web netconfig failed when used with the WeChat applet

WebSocket

• Added additional parameters to the AT+WSCFG command to configure certificates in WebSocket

Bluetooth

• Fixed AT command response interleaving issues causing data corruption
• Fixed AT command response issues where the \r character was missing
• Added BLE light sleep support on esp32c2
• Added BLE adv type information
• Fixed missing +BLESCANDONE issue
• Resolved data loss issue in BLE passthrough mode
• Optimized BLE WRITE/INDICATE flow control mechanism
• Fixed crash in BLE transparent transmission mode
• Fixed AT+BTENCCLEAR not properly clearing BT pairing information
• Fixed BLE_TT_MODE printed twice in BLE passthrough mode
• Fixed missing +WRITE response
• Fixed BLUFI memory leak
• Fixed issue where MTU size greater than attribute length caused data transmission failure
• Fixed that AT+RFPOWER query not returning BLE power when using nimble protocol
• Fixed extra +BLEDISCONN message when sending AT+BLEDISCONN=0

Interface

• Optimized the UART1 clock source
• Fixed a potential crash when AT was not ready but received data
• Fixed a potential UART voltage fluctuation during light sleep
• Fixed some socket interface issues
• Fixed an SDIO compilation warning
• Fixed a heap‑corruption issue when using the SDIO interface

System

• esp-idf version updated to ~v5.4.2
• Added an unfilled factory binary
• Added a checker to prevent duplicate keys in *.defaults
• Added some return value checks for driver commands
• Added pre_wakeup_callback and process_light_sleep hook events
• Added a hook function for memory allocation failure
• Added the esp_at_ready_before() API to perform tasks before ESP‑AT is ready
• Added the at_exe_cmd() API to execute AT commands via ESP‑AT itself
• Supported the new log system and improved log readability
• Added support to configure the default system storage mode
• Added support to print the firmware source
• Added support to override default configurations
• Optimized resources to increase available RAM
• Reduced power consumption when a beacon is lost
• Optimized the root CMake file
• Decoupled Wi‑Fi and BLE functions from the base commands
• Renamed esp_at_get_netconn_count() to esp_at_get_netconn_max_count()
• Exposed esp_at_get_smartconfig_start_config() API
• Reconfigured TWDT to disable the panic trigger when AT debug is enabled
• Provided some weak symbols to allow external overriding (esp_at_nvs_set_xxx/esp_at_nvs_get_xxx/esp_at_log_write)
• Fixed an issue where the factory binary was not generated in some cases
• Fixed an issue where patches could not be applied on Windows
• Fixed several MCU wake‑up issues

Optimization

• TCP & SSL: TCP/SSL connections are now proactively closed immediately when their associated netif state changes (netif down, stop, or lost IP). In previous versions, the connections would remain open until a keep-alive timeout, send timeout, or max retry threshold was reached - often taking tens of seconds to close. This change significantly reduces latency in connection teardown and improves system responsiveness.
• Upgraded supported python version and some package versions
• Optimized patching process
• Replaced the previous script with esptool.py merge_bin
• Fixed a potential issue where the patch is applied multiple times
• Fixed an issue where gatts_cfg was excessively modified by the at.py script

Examples

• Added a fatfs_to_http_server example
• Added a http_get_to_fatfs example
• Added a WebSocket example document
• Added an AT interface security example

Documentation

• Improved documentation for AT commands, examples, and development
• Added richer content for new features and changes
• Added a chatbox on docs.espressif.com/projects/esp-at
• Added a disclaimer for the esp-at project
• Added some document format checks

ESP32C3-AT

Documentation for Release v4.1.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v4.1.0.0/esp32c3/index.html. ESP32C3-AT v4.1.0.0 is a major update for ESP32C3-AT v3.3.0.0.

The firmwares:

• ESP32-C3-MINI-1-AT-V4.1.0.0.zip

This is the list of changes since release v3.3.0.0:

Known Issues

• AT+FS may fail after repeated read/write operations

Changelog

Basic

• Added the AT+SYSRAM setup command to detail memory capacity
• Added the AT+SYSROLLBACK query command to obtain the address and version of the current a...

ESP8266 AT Release v2.2.2.0

The documentation for ESP-AT v2.2.2.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v2.2.0.0_esp8266/. This release is a minor update to ESP-AT v2.2.1.0.

ESP-WROOM-02-AT-V2.2.2.0.zip

Breaking Changes Since Release v2.2.1.0

• ESP8266_RTOS_SDK version update: Upgraded to release v3.4 (ff16a35c).
• Disclaimer update: Included an important disclaimer for ESP-AT.

1. Feature

• Added the AT+USERWKMCUCFG and AT+USERMCUSLEEP commands to wake up MCU.
• Added the AT+CIPSSLCCIPHER command to specify ssl cipher suite.
• Added AT+CIPSTATE command to query connection state.
• Added fallback DNS server. AT has two DNS servers ("208.67.222.222" and "8.8.8.8") by default.
• Added the AT+MQTTLONGCLIENTID command to set MQTT client ID.
• Added the AT+MQTTLONGUSERNAME command to set MQTT username.
• Added the AT+MQTTLONGPASSWORD command to set MQTT password.
• AT+WEBSERVER: Wi-Fi provisioning supports the special character in SSID and password.

2. Bugfix

2.1 Wi-Fi

• Fixed an issue where AT+CWJAP occasionally returned an incorrect reason code.
• Fixed an issue where AT+CWSTATE occasionally returned an incorrect state.
• Fixed a potential crash when the lSSID length was exactly 32 bytes or the password length was 64 bytes.
• Fixed an issue where AT+CWLAP occasionally returned an ERROR.
• Fixed an auto-connection issue with WPA2 Enterprise AP. Users should always use AT+CWJEAP to connect to a WPA2 Enterprise AP.
• Fixed an issue where the +CWJAP error code might be printed before the "WIFI DISCONNECT" message.

2.2 TCP/IP

• Fixed an issue where the AT+CIPDNS query command returned an incorrect configuration.
• Fixed an issue where AT+CIPSERVER=0,1 did not correctly close clients connected to the ESP TCP server.
• Fixed an issue where setting AT+CIPSERVER=5 returned "Have 255 Connections" sometimes.
• Fixed an issue where AT+CIPTCPOPT send timeout parameter failed to work sometimes.
• Fixed an issue with active TCP data writes in passive mode.
• Fixed an occasional crash in passthrough mode caused by a socket close.
• Fixed +IPD report loss when the TCP connection was reopened while AT was acting as a server.
• Fixed an occasional failure when AT+CIPSERVERMAXCONN=5 was set.
• Fixed an issue where AT+CIPSTO did not reset the timer after sending data.
• Fixed an ssl connection issue where the connection was dropped after receiving data when AT+CIPRECVMODE=1 was used.
• Updated the "+IPD" command to report actual ssl available bytes whenever possible, except when TCP buffers data but SSL does not.
• Fixed a potential illegal assignment issue with the AT+CIPTCPOPT command in multiple connections.
• Fixed an issue where AT+CIPTCPOPT did not work when ESP-AT operated as a server.
• Fixed an issue where AT+CIPSTART could not establish multiple UDP transmissions on the same port.
• Fixed an occasional disconnection issue when the link state changed.
• Corrected an invalid maximum number of tcp retransmission.
• Fixed an issue where the maximum parameter length for AT+CIPSSLCCN and AT+CIPSSLCSNI could not be set to 64 bytes.

2.3 Application

• Removed extra space in AT+HTTPCLIENT HEAD response.
• Fixed an issue where AT+HTTPCPOST response returned the wrong command name when additional POST data was appended.

2.4 System

• Fixed an issue of high power consumption after power-on when AT+CWMODE=0 was set.
• Fixed a potential issue where uart data was blocked in the RX ring buffer.
• Fixed several potential busy p... issues occurring occasionally.
• Fixed a problem where GPIO15 did not function correctly in custom modules based on ESP8266.
• Fixed an occasional system hang caused by a deadlock.
• Fixed a crash occurring when invalid GPIO wake-up configurations were set.

3. Optimization

• Removed potential NVS writes at startup when dirty data was detected during NVS read operations.
• Enhanced handling of multiple connections by ensuring all available bytes from one link are read before processing the next.
• Added parameters validation for the AT+CIPTCPOPT command.

ESP32-C2 AT Release v3.3.1.0

Documentation for Release v3.3.1.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v3.3.1.0/esp32c2/index.html. ESP32-C2 AT v3.3.1.0 is the first released version of AT firmware for ESP32-C2 ECO4 (Rev v2.0) series chips.

The firmwares:

• ESP32-C2-4MB-G2-AT-V3.3.1.0.zip
• ESP32-C2-2MB-G2-AT-V3.3.1.0.zip

Feature

Basic AT Commands

• AT: Test AT startup.
• AT+RST: Restart a module.
• AT+GMR: Check version information.
• AT+CMD: List all AT commands and types supported in current firmware.
• AT+GSLP: Enter Deep-sleep mode.
• ATE: Configure AT commands echoing.
• AT+RESTORE: Restore factory default settings of the module.
• AT+SAVETRANSLINK: Set whether to enter Passthrough Mode on power-up.
• AT+TRANSINTVL: Set the data transmission interval in the Passthrough Mode.
• AT+UART_CUR: Current UART configuration, not saved in flash.
• AT+UART_DEF: Default UART configuration, saved in flash.
• AT+SLEEP: Set the sleep mode.
• AT+SYSRAM: Query current remaining heap size and minimum heap size.
• AT+SYSMSG: Query/Set System Prompt Information.
• AT+SYSMSGFILTER: Enable or disable the system message filter.
• AT+SYSMSGFILTERCFG: Query/Set the system message filters.
• AT+SYSFLASH: Query/Set User Partitions in Flash.
• AT+SYSMFG: Query/Set manufacturing nvs User Partitions.
• AT+RFPOWER: Query/Set RF TX Power.
• AT+SYSROLLBACK: Roll back to the previous firmware.
• AT+SYSTIMESTAMP: Query/Set local time stamp.
• AT+SYSLOG: Enable or disable the AT error code prompt.
• AT+SLEEPWKCFG: Query/Set the light-sleep wakeup source and awake GPIO.
• AT+SYSSTORE: Query/Set parameter store mode.
• AT+SYSREG: Read/write the register.

Wi-Fi AT Commands

• AT+CWINIT: Initialize/Deinitialize Wi-Fi driver.
• AT+CWMODE: Set the Wi-Fi mode (Station/SoftAP/Station+SoftAP).
• AT+CWSTATE: Query the Wi-Fi state and Wi-Fi information.
• AT+CWJAP: Connect to an AP.
• AT+CWRECONNCFG: Query/Set the Wi-Fi reconnecting configuration.
• AT+CWLAPOPT: Set the configuration for the command AT+CWLAP.
• AT+CWLAP: List available APs.
• AT+CWQAP: Disconnect from an AP.
• AT+CWSAP: Query/Set the configuration of an ESP32-C2 SoftAP.
• AT+CWLIF: Obtain IP address of the station that connects to an ESP32-C2 SoftAP.
• AT+CWQIF: Disconnect stations from an ESP32-C2 SoftAP.
• AT+CWDHCP: Enable/disable DHCP.
• AT+CWDHCPS: Query/Set the IPv4 addresses allocated by an ESP32-C2 SoftAP DHCP server.
• AT+CWAUTOCONN: Connect to an AP automatically when powered on.
• AT+CWAPPROTO: Query/Set the 802.11 b/g/n protocol standard of SoftAP mode.
• AT+CWSTAPROTO: Query/Set the 802.11 b/g/n protocol standard of station mode.
• AT+CIPSTAMAC: Query/Set the MAC address of an ESP32-C2 station.
• AT+CIPAPMAC: Query/Set the MAC address of an ESP32-C2 SoftAP.
• AT+CIPSTA: Query/Set the IP address of an ESP32-C2 station.
• AT+CIPAP: Query/Set the IP address of an ESP32-C2 SoftAP.
• AT+CWSTARTSMART: Start SmartConfig.
• AT+CWSTOPSMART: Stop SmartConfig.
• AT+WPS: Enable the WPS function.
• AT+MDNS: Configure the mDNS function.
• AT+CWJEAP: Connect to a WPA2 Enterprise AP.
• AT+CWHOSTNAME: Query/Set the host name of an ESP32-C2 station.
• AT+CWCOUNTRY: Query/Set the Wi-Fi Country Code.

TCP/IP AT Commands

• AT+CIPV6: Enable/disable the network of Internet Protocol Version 6 (IPv6).
• AT+CIPSTATE: Obtain the TCP/UDP/SSL connection information.
• AT+CIPSTATUS (deprecated): Obtain the TCP/UDP/SSL connection status and information.
• AT+CIPDOMAIN: Resolve a Domain Name.
• AT+CIPSTART: Establish TCP connection, UDP transmission, or SSL connection.
• AT+CIPSTARTEX: Establish TCP connection, UDP transmission, or SSL connection with an automatically assigned ID.
• [Data Mode Only] +++: Exit from the data mode.
• AT+SAVETRANSLINK: Set whether to enter Wi-Fi Passthrough Mode on power-up.
• AT+CIPSEND: Send data in the normal transmission mode or Wi-Fi normal transmission mode.
• AT+CIPSENDL: Send long data in paraller in the normal transmission mode.
• AT+CIPSENDLCFG: Set the configuration for the command AT+CIPSENDL.
• AT+CIPSENDEX: Send data in the normal transmission mode in expanded ways.
• AT+CIPCLOSE: Close TCP/UDP/SSL connection.
• AT+CIFSR: Obtain the local IP address and MAC address.
• AT+CIPMUX: Enable/disable the multiple connections mode.
• AT+CIPSERVER: Delete/create a TCP/SSL server.
• AT+CIPSERVERMAXCONN: Query/Set the maximum connections allowed by a server.
• AT+CIPMODE: Query/Set the transmission mode.
• AT+CIPSTO: Query/Set the local TCP Server Timeout.
• AT+CIPSNTPCFG: Query/Set the time zone and SNTP server.
• AT+CIPSNTPTIME: Query the SNTP time.
• AT+CIPSNTPINTV: Query/Set the SNTP time synchronization interval.
• AT+CIPFWVER: Query the existing AT firmware version on the server.
• AT+CIUPDATE: Upgrade the firmware through Wi-Fi.
• AT+CIPDINFO: Set “+IPD” message mode.
• AT+CIPSSLCCONF: Query/Set SSL clients.
• AT+CIPSSLCCN: Query/Set the Common Name of the SSL client.
• AT+CIPSSLCSNI: Query/Set SSL client Server Name Indication (SNI).
• AT+CIPSSLCALPN: Query/Set SSL client Application Layer Protocol Negotiation (ALPN).
• AT+CIPSSLCPSK: Query/Set SSL client Pre-shared Key (PSK) in string format.
• AT+CIPSSLCPSKHEX: Query/Set SSL client Pre-shared Key (PSK) in hexadecimal format.
• AT+CIPRECONNINTV: Query/Set the TCP/UDP/SSL reconnection interval for the Wi-Fi normal transmission mode.
• AT+CIPRECVTYPE: Query/Set socket receiving mode.
• AT+CIPRECVDATA: Obtain socket data in passive receiving mode.
• AT+CIPRECVLEN: Obtain socket data length in passive receiving mode.
• AT+PING: Ping the remote host.
• AT+CIPDNS: Query/Set DNS server information.
• AT+CIPTCPOPT: Query/Set the socket options.

Bluetooth® Low Energy AT Commands (ESP32-C2-4MB-G2 only)

• AT+BLUFI: Start or Stop BluFi.
• AT+BLUFINAME: Query/Set BluFi device name.
• AT+BLUFISEND: Send user-customized data over BluFi.

MQTT AT Commands

• AT+MQTTUSERCFG: Set MQTT user configuration.
• AT+MQTTLONGCLIENTID: Set MQTT client ID.
• AT+MQTTLONGUSERNAME: Set MQTT username.
• AT+MQTTLONGPASSWORD: Set MQTT password.
• AT+MQTTCONNCFG: Set configuration of MQTT connection.
• AT+MQTTALPN: Set MQTT Application Layer Protocol Negotiation (ALPN).
• AT+MQTTSNI: Set MQTT Server Name Indication (SNI).
• AT+MQTTCONN: Connect to MQTT Brokers.
• AT+MQTTPUB: Publish MQTT Messages in string.
• AT+MQTTPUBRAW: Publish long MQTT messages.
• AT+MQTTSUB: Subscribe to MQTT topics.
• AT+MQTTUNSUB: Unsubscribe from MQTT topics.
• AT+MQTTCLEAN: Close MQTT connections.

HTTP AT Commands (ESP32-C2-4MB-G2 only)

• AT+HTTPCLIENT: Send HTTP Client Request.
• AT+HTTPGETSIZE: Get HTTP Resource Size.
• AT+HTTPCGET: Get HTTP Resource.
• AT+HTTPCPOST: Post HTTP data of specified length.
• AT+HTTPCPUT: Put HTTP data of specified length.
• AT+HTTPURLCFG: Set/Get long HTTP URL.
• AT+HTTPCHEAD: Set/Query HTTP request headers.

User AT Commands

• AT+USERRAM: Operate user’s free RAM.
• AT+USEROTA: Upgrade the firmware according to the specified URL.
• AT+USERWKMCUCFG: Configure how AT wakes up MCU.
• AT+USERMCUSLEEP: MCU indicates its sleep state.
• AT+USERDOCS: Query the ESP-AT user guide for current firmware.

v3.2.1.0 Release Notes

v3.2.1.0 is released for ESP32. The changes since the v3.2.0.0 are as follows.

ESP32-AT

Documentation for Release v3.2.1.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v3.2.0.0/esp32/index.html. ESP32-AT v3.2.1.0 is a minor update for ESP32-AT v3.2.0.0.

The firmwares:

• ESP32-WROOM-32-AT-V3.2.1.0.zip
• ESP32-SOLO-AT-V3.2.1.0.zip
• ESP32-PICO-D4-AT-V3.2.1.0.zip
• ESP32-MINI-1-AT-V3.2.1.0.zip

This is the list of changes since release v3.2.0.0:

Optimization

• Optimized the time cost of the AT+BLEGATTSSRVCRE command by removing some logs

v3.4.0.0 Release Notes

v3.4.0.0 is released for ESP32 and ESP32-S2. The changes since the previous version are as follows.

• ESP32-AT
• ESP32S2-AT

ESP32-AT

Documentation for Release v3.4.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v3.4.0.0/esp32/index.html. ESP32-AT v3.4.0.0 is a major update for ESP32-AT v3.2.0.0.

The firmwares:

• ESP32-WROOM-32-AT-V3.4.0.0.zip
• ESP32-SOLO-AT-V3.4.0.0.zip
• ESP32-PICO-D4-AT-V3.4.0.0.zip
• ESP32-MINI-1-AT-V3.4.0.0.zip

This is the list of changes since release v3.2.0.0:

Breaking Changes

• esp-idf version updated to v5.0.6
• RF power: Fixed the issue that the actual wifi transmit power didn't match the settings. The default configuration of wifi transmit power is 19.5 dBm, but the actual wifi transmit power may be slightly lower than the settings. This is because the wifi transmit power is limited by your country code according to phy_multiple_init_data.bin configuration. In the current version, esp-at disabled multiple phy init data bin to improve the wifi transmit power (rf power is no longer limited by your country code).

1. Feature

1.1 TCP/IP

• Added the AT+CIPRECVTYPE command to set recv mode for each connection
• AT+CIPRECVLEN query command can return the real data length now

1.2 Application Layer

• AT+MQTTCONNCFG: Enlarged lwt msg length to 128 bytes
• Added the AT+MQTTSNI command to set MQTT server name indication

2. Bugfix

2.1 Wi-Fi

• AT+CWLAP: Fixed an issue where executing AT+CWLAP may return an ERROR when the AT+CWRECONNCFG command is sent immediately after the Wi-Fi disconnection

2.2 TCP/IP

• AT+PING: Fixed an issue that cannot ping a linklocal ipv6 address
• Fixed an ssl issue where "CLOSED" was output before reading all data in passive mode
• Fixed a potential ssl crash caused when mbedtls dynamic buffer feature is used and an ssl renegotiation occurs
• Fixed an issue where esp-tls is unable to parse ECC keys

2.3 System

• Fixed the issue that AT could not work immediately after restart and prompt ready
• Fixed an AT+SYSFLASH crash issue if a large amount of data is read
• Fixed a potential GPIO voltage fluctuation issue during light-sleep

2.4 Bluetooth

• Fixed BLE don't print ble connection params update fail issue
• Fixed BLE memory leak issue

3. Optimization

• Optimized sntp startup delay and receive timeout to speed up sntp time acquisition
• Re-organized the gitlab ci
• Re-organized the main directory of the esp-at repository
• Added some debug options to allow different kinds of esp-at debug output

ESP32S2-AT

Documentation for Release v3.4.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v3.4.0.0/esp32s2/index.html. ESP32S2-AT v3.4.0.0 is a major update for ESP32S2-AT v2.1.0.0.

The firmware:

• ESP32-S2-MINI-AT-V3.4.0.0.zip

This is the list of changes since release v2.1.0.0:

Breaking Changes

• esp-idf version updated to v5.0.6

1. Feature

1.1 Basic

Added more Basic AT commands:

• AT+CMD: List all AT commands and types supported in the current firmware.
• AT+TRANSINTVL: Set the data transmission interval in the Passthrough Mode.
• AT+SYSMSGFILTER: Enable or disable the system message filter.
• AT+SYSMSGFILTERCFG: Query/Set the system message filters.
• AT+SYSMFG: Query/Set manufacturing nvs User Partitions.
• AT+SYSREG: Read/write the register.

1.2 Wi-Fi

Added more Wi-Fi AT commands:

• AT+CWINIT: Initialize/Deinitialize Wi-Fi driver.
• AT+CWSTATE: Query the Wi-Fi state and Wi-Fi information.
• AT+CWRECONNCFG: Query/Set the Wi-Fi reconnecting configuration.

1.3 TCP/IP

Added more TCP/IP AT Commands:

• AT+CIPV6: Enable/disable the network of Internet Protocol Version 6 (IPv6).
• AT+CIPSTATE: Obtain the TCP/UDP/SSL connection information.
• AT+CIPSENDL: Send long data in parallel in the normal transmission mode.
• AT+CIPSENDLCFG: Set the configuration for the command AT+CIPSENDL.
• AT+CIPSNTPINTV: Query/Set the SNTP time synchronization interval.
• AT+CIPFWVER: Query the existing AT firmware version on the server.
• AT+CIPSSLCCN: Query/Set the Common Name of the SSL client.
• AT+CIPSSLCSNI: Query/Set SSL client Server Name Indication (SNI).
• AT+CIPSSLCALPN: Query/Set SSL client Application Layer Protocol Negotiation (ALPN).
• AT+CIPSSLCPSK: Query/Set SSL client Pre-shared Key (PSK) in string format.
• AT+CIPSSLCPSKHEX: Query/Set SSL client Pre-shared Key (PSK) in hexadecimal format.
• AT+CIPRECVTYPE: Query/Set socket receiving mode.

1.4 MQTT

Added more MQTT AT Commands:

• AT+MQTTLONGCLIENTID: Set MQTT client ID
• AT+MQTTLONGUSERNAME: Set MQTT username
• AT+MQTTLONGPASSWORD: Set MQTT password
• AT+MQTTALPN: Set MQTT Application Layer Protocol Negotiation (ALPN)
• AT+MQTTSNI: Set MQTT Server Name Indication (SNI)

1.5 HTTP

Added more HTTP AT Commands:

• AT+HTTPCGET: Get HTTP Resource
• AT+HTTPCPOST: Post HTTP data of specified length
• AT+HTTPCPUT: Put HTTP data of specified length
• AT+HTTPURLCFG: Set/Get long HTTP URL
• AT+HTTPCHEAD: Set/Query HTTP request headers

1.6 User

Added new User AT Commands:

• AT+USERRAM: Operate user’s free RAM.
• AT+USEROTA: Upgrade the firmware according to the specified URL.
• AT+USERWKMCUCFG: Configure how AT wakes up MCU.
• AT+USERMCUSLEEP: MCU indicates its sleep state.
• AT+USERDOCS: Query the ESP-AT user guide for the current firmware.

2. Attention

Due to the long time without a new firmware release for ESP32-S2, this release has significant changes. If you want to know more information, please refer to some ESP32 release notes:

• v3.2.0.0
• v2.4.0.0
• v2.2.0.0

v3.3.0.0 Release Notes

v3.3.0.0 is released for ESP32-C2 and ESP32-C3. The changes since the previous version are as follows.

• ESP32C2-AT
• ESP32C3-AT

ESP32C2-AT

Documentation for Release v3.3.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v3.3.0.0/esp32c2/index.html ESP32C2-AT v3.3.0.0 is a major update for ESP32C2-AT v3.1.0.0.

The firmwares:

• ESP32-C2-4MB-AT-V3.3.0.0.zip
• ESP32-C2-2MB-AT-V3.3.0.0.zip

This is the list of changes since release v3.1.0.0:

Breaking Changes

• esp-idf version updated to v5.0.6

1. Feature

1.1 TCP/IP

• Added the AT+CIPSSLCPSKHEX command to set SSL client pre-shared key in hexadecimal format
• Added the AT+CIPRECVTYPE command to set recv mode for each connection
• AT+CIPRECVLEN query command can return the real data length now

1.2 Application Layer

• AT+CIPSNTPCFG: Added timezone query and timezone set when SNTP was disabled
• AT+MQTTCONNCFG: Enlarged lwt msg length to 128 bytes
• Added the AT+MQTTSNI command to set MQTT server name indication

2. Bugfix

2.1 Wi-Fi

• AT+CWLAP: Fixed an issue where executing AT+CWLAP may return an ERROR when the AT+CWRECONNCFG command is sent immediately after the Wi-Fi disconnection

2.2 TCP/IP

• AT+PING: Fixed an issue that cannot ping a linklocal ipv6 address
• Fixed an SSL issue where "CLOSED" was output before reading all data in passive mode
• Fixed a potential SSL crash if mbedtls dynamic buffer feature is used and SSL renegotiation occurs
• Fixed an issue where esp-tls is unable to parse ECC keys

2.3 System

• Fixed the issue that AT+SYSMFG read operation returned wrong length
• Fixed the issue where AT cannot work immediately after restart and prompt ready
• Fixed an AT+SYSFLASH crash issue if read a large amount of data

3. Optimization

• Optimized sntp startup delay and receive timeout to speedup sntp time acquisition
• Disabled relinker feature to get rid of potential crashes
• Optimized the available ram size
• Re-organized the gitlab ci
• Re-organized the main directory of the esp-at repository
• Added some debug options to allow different kinds of esp-at debug output

ESP32C3-AT

Documentation for Release v3.3.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v3.3.0.0/esp32c3/index.html ESP32C3-AT v3.3.0.0 is a major update for ESP32C3-AT v3.2.0.0.

The firmware:

• ESP32-C3-MINI-1-AT-V3.3.0.0.zip

This is the list of changes since release v3.2.0.0:

Breaking Changes

• esp-idf version updated to v5.0.6
• RF power: Fixed an issue where the actual wifi transmit power didn't match the settings. The default configuration of wifi transmit power is 19.5 dBm, but the actual wifi transmit power may be slightly lower than the settings, this is because the wifi transmit power is limited by your country code according to phy_multiple_init_data.bin configuration. In the current version, esp-at disabled multiple phy init data bin to improve the wifi transmit power (RF power is no longer limited by your country code).

1. Feature

1.1 TCP/IP

• Added the AT+CIPRECVTYPE command to set recv mode for each connection
• AT+CIPRECVLEN query command can return the real data length now

1.2 Application Layer

• AT+MQTTCONNCFG: Enlarged lwt msg length to 128 bytes
• Added the AT+MQTTSNI command to set MQTT server name indication

2. Bugfix

2.1 Wi-Fi

• AT+CWLAP: Fixed an issue where executing AT+CWLAP may return an ERROR when the AT+CWRECONNCFG command is sent immediately after the Wi-Fi disconnection
• Fixed an issue where init and deinit the wifi could lead to Wi-Fi scan issue

2.2 TCP/IP

• AT+PING: Fixed an issue that cannot ping a link-local ipv6 address
• Fixed an SSL issue where "CLOSED" was output before reading all data in passive mode
• Fixed a potential SSL crash if mbedtls dynamic buffer feature is used and SSL renegotiation occurs
• Fixed an issue where esp-tls is unable to parse ECC keys

2.3 System

• Fixed the issue where AT cannot work immediately after restart and prompt ready
• Fixed an AT+SYSFLASH crash issue if a large amount of data is read

2.4 Bluetooth

• Fixed ble init fail issue
• Fixed ble disconnection will crash issue
• Fixed ble connection timeout issue

3. Optimization

• Optimized SNTP startup delay and receive timeout to speed up SNTP time acquisition
• Re-organized the GitLab CI
• Re-organized the main directory of the esp-at repository
• Added some debug options to allow different kinds of esp-at debug output

ESP32-C6 AT Release v4.0.0.0

Documentation for Release v4.0.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v4.0.0.0/esp32c6/index.html

ESP32-C6 AT v4.0.0.0 is the first released version of AT firmware for ESP32-C6.

The firmware:

• ESP32-C6-4MB-V4.0.0.0.zip

Known Issues

• Unable to use Long Range mode in the AT+CWSTAPROTO and AT+CWAPPROTO commands.
• Deinit BluFi will result in a memory leak.
• The third BLE connection cannot be paired.
• In some scenarios, there may be no prompt to write the attribute value of UUID 0x2902.

Features

Basic AT Commands

• AT: Test AT startup.
• AT+RST: Restart a module.
• AT+GMR: Check version information.
• AT+CMD: List all AT commands and types supported in current firmware.
• AT+GSLP: Enter Deep-sleep mode.
• ATE: Configure AT commands echoing.
• AT+RESTORE: Restore factory default settings of the module.
• AT+SAVETRANSLINK: Set whether to enter Passthrough Mode on power-up.
• AT+TRANSINTVL: Set the data transmission interval in the Passthrough Mode.
• AT+UART_CUR: Current UART configuration, not saved in flash.
• AT+UART_DEF: Default UART configuration, saved in flash.
• AT+SLEEP: Set the sleep mode.
• AT+SYSRAM: Query current remaining heap size and minimum heap size.
• AT+SYSMSG: Query/Set System Prompt Information.
• AT+SYSMSGFILTER: Enable or disable the system message filter.
• AT+SYSMSGFILTERCFG: Query/Set the system message filters.
• AT+SYSFLASH: Query/Set User Partitions in Flash.
• AT+SYSMFG: Query/Set manufacturing nvs User Partitions.
• AT+RFPOWER: Query/Set RF TX Power.
• AT+SYSROLLBACK: Roll back to the previous firmware.
• AT+SYSTIMESTAMP: Query/Set local time stamp.
• AT+SYSLOG: Enable or disable the AT error code prompt.
• AT+SLEEPWKCFG: Query/Set the light-sleep wakeup source and awake GPIO.
• AT+SYSSTORE: Query/Set parameter store mode.
• AT+SYSREG: Read/write the register.

Wi-Fi AT Commands

• AT+CWINIT: Initialize/Deinitialize Wi-Fi driver.
• AT+CWMODE: Set the Wi-Fi mode (Station/SoftAP/Station+SoftAP).
• AT+CWSTATE: Query the Wi-Fi state and Wi-Fi information.
• AT+CWJAP: Connect to an AP.
• AT+CWRECONNCFG: Query/Set the Wi-Fi reconnecting configuration.
• AT+CWLAPOPT: Set the configuration for the command AT+CWLAP.
• AT+CWLAP: List available APs.
• AT+CWQAP: Disconnect from an AP.
• AT+CWSAP: Query/Set the configuration of an ESP32-C6 SoftAP.
• AT+CWLIF: Obtain IP address of the station that connects to an ESP32-C6 SoftAP.
• AT+CWQIF: Disconnect stations from an ESP32-C6 SoftAP.
• AT+CWDHCP: Enable/disable DHCP.
• AT+CWDHCPS: Query/Set the IPv4 addresses allocated by an ESP32-C6 SoftAP DHCP server.
• AT+CWAUTOCONN: Connect to an AP automatically when powered on.
• AT+CWAPPROTO: Query/Set the 802.11 b/g/n protocol standard of SoftAP mode.
• AT+CWSTAPROTO: Query/Set the 802.11 b/g/n protocol standard of station mode.
• AT+CIPSTAMAC: Query/Set the MAC address of an ESP32-C6 station.
• AT+CIPAPMAC: Query/Set the MAC address of an ESP32-C6 SoftAP.
• AT+CIPSTA: Query/Set the IP address of an ESP32-C6 station.
• AT+CIPAP: Query/Set the IP address of an ESP32-C6 SoftAP.
• AT+CWSTARTSMART: Start SmartConfig.
• AT+CWSTOPSMART: Stop SmartConfig.
• AT+WPS: Enable the WPS function.
• AT+MDNS: Configure the mDNS function.
• AT+CWJEAP: Connect to a WPA2 Enterprise AP.
• AT+CWHOSTNAME: Query/Set the host name of an ESP32-C6 station.
• AT+CWCOUNTRY: Query/Set the Wi-Fi Country Code.

TCP/IP AT Commands

• AT+CIPV6: Enable/disable the network of Internet Protocol Version 6 (IPv6).
• AT+CIPSTATE: Obtain the TCP/UDP/SSL connection information.
• AT+CIPSTATUS (deprecated): Obtain the TCP/UDP/SSL connection status and information.
• AT+CIPDOMAIN: Resolve a Domain Name.
• AT+CIPSTART: Establish TCP connection, UDP transmission, or SSL connection.
• AT+CIPSTARTEX: Establish TCP connection, UDP transmission, or SSL connection with an automatically assigned ID.
• [Data Mode Only] +++: Exit from the data mode.
• AT+SAVETRANSLINK: Set whether to enter Wi-Fi Passthrough Mode on power-up.
• AT+CIPSEND: Send data in the normal transmission mode or Wi-Fi normal transmission mode.
• AT+CIPSENDL: Send long data in parallel in the normal transmission mode.
• AT+CIPSENDLCFG: Set the configuration for the command AT+CIPSENDL.
• AT+CIPSENDEX: Send data in the normal transmission mode in expanded ways.
• AT+CIPCLOSE: Close TCP/UDP/SSL connection.
• AT+CIFSR: Obtain the local IP address and MAC address.
• AT+CIPMUX: Enable/disable the multiple connections mode.
• AT+CIPSERVER: Delete/create a TCP/SSL server.
• AT+CIPSERVERMAXCONN: Query/Set the maximum connections allowed by a server.
• AT+CIPMODE: Query/Set the transmission mode.
• AT+CIPSTO: Query/Set the local TCP Server Timeout.
• AT+CIPSNTPCFG: Query/Set the time zone and SNTP server.
• AT+CIPSNTPTIME: Query the SNTP time.
• AT+CIPSNTPINTV: Query/Set the SNTP time synchronization interval.
• AT+CIPFWVER: Query the existing AT firmware version on the server.
• AT+CIUPDATE: Upgrade the firmware through Wi-Fi.
• AT+CIPDINFO: Set “+IPD” message mode.
• AT+CIPSSLCCONF: Query/Set SSL clients.
• AT+CIPSSLCCN: Query/Set the Common Name of the SSL client.
• AT+CIPSSLCSNI: Query/Set SSL client Server Name Indication (SNI).
• AT+CIPSSLCALPN: Query/Set SSL client Application Layer Protocol Negotiation (ALPN).
• AT+CIPSSLCPSK: Query/Set SSL client Pre-shared Key (PSK) in string format.
• AT+CIPSSLCPSKHEX: Query/Set SSL client Pre-shared Key (PSK) in hexadecimal format.
• AT+CIPRECONNINTV: Query/Set the TCP/UDP/SSL reconnection interval for the Wi-Fi normal transmission mode.
• AT+CIPRECVTYPE: Query/Set socket receiving mode.
• AT+CIPRECVDATA: Obtain socket data in passive receiving mode.
• AT+CIPRECVLEN: Obtain socket data length in passive receiving mode.
• AT+PING: Ping the remote host.
• AT+CIPDNS: Query/Set DNS server information.
• AT+CIPTCPOPT: Query/Set the socket options.

Bluetooth® Low Energy AT Commands

• AT+BLEINIT: Bluetooth LE initialization.
• AT+BLEADDR: Query/Set Bluetooth LE device address.
• AT+BLENAME: Query/Set Bluetooth LE device name.
• AT+BLESCANPARAM: Query/Set parameters of Bluetooth LE scanning.
• AT+BLESCAN: Enable Bluetooth LE scanning.
• AT+BLESCANRSPDATA: Set Bluetooth LE scan response.
• AT+BLEADVPARAM: Query/Set parameters of Bluetooth LE advertising.
• AT+BLEADVDATA: Set Bluetooth LE advertising dATa.
• AT+BLEADVDATAEX: AutomATically set Bluetooth LE advertising dATa.
• AT+BLEADVSTART: Start Bluetooth LE advertising.
• AT+BLEADVSTOP: Stop Bluetooth LE advertising.
• AT+BLECONN: Establish Bluetooth LE connection.
• AT+BLECONNPARAM: Query/UpdATe parameters of Bluetooth LE connection.
• AT+BLEDISCONN: End Bluetooth LE connection.
• AT+BLEDATALEN: Set Bluetooth LE dATa packet length.
• AT+BLECFGMTU: Set Bluetooth LE MTU length.
• AT+BLEGATTSSRV: GATTS discovers services.
• AT+BLEGATTSCHAR: GATTS discovers characteristics.
• AT+BLEGATTSNTFY: Notify a client of the value of a characteristic value from the server.
• AT+BLEGATTSIND: IndicATe the characteristic value from the server to a client.
• AT+BLEGATTSSETATTR: GATTS sets characteristics.
• AT+BLEGATTCPRIMSRV: Generic ATtributes Client (GATTC) discovers primary services.
• AT+BLEGATTCINCLSRV: GATTC discovers included services.
• AT+BLEGATTCCHAR: GATTC discovers characteristics.
• AT+BLEGATTCRD: GATTC reads characteristics.
• AT+BLEGATTCWR: GATTC writes characteristics.
• AT+BLESPPCFG: Query/Set Bluetooth LE SPP parameters.
• AT+BLESPP: Enter Bluetooth LE SPP mode.
• AT+SAVETRANSLINK: Set whether to enter Bluetooth LE :term:Passthrough Mode on power-up.
• AT+BLESECPARAM: Query/Set Bluetooth LE encryption parameters.
• AT+BLEENC: InitiATe Bluetooth LE encryption request.
• AT+BLEENCRSP: Respond to the pairing request from the peer device.
• AT+BLEKEYREPLY: Reply the key value to the peer device.
• AT+BLECONFREPLY: Reply the confirm value to the peer device in the legacy connection stage.
• AT+BLEENCDEV: Query bonded Bluetooth LE encryption device list.
• AT+BLEENCCLEAR: Clear Bluetooth LE encryption device list.
• AT+BLESETKEY: Set Bluetooth LE stATic pair key.
• AT+BLEPERIODICDATA: Set Bluetooth LE periodic advertising dATa.
• AT+BLEPERIODICSTART: Start Bluetooth LE periodic advertising.
• AT+BLEPERIODICSTOP: Stop Bluetooth LE periodic advertising.
• AT+BLESYNCSTART: Start to synchronize with periodic advertising.
• AT+BLESYNCSTOP: Stop synchronizing with periodic advertising.
• AT+BLEREADPHY: Query the current transmitter PHY.
• AT+BLESETPHY: Set the current transmitter PHY.

MQTT AT Commands

• AT+MQTTUSERCFG: Set MQTT user configuration.
• AT+MQTTLONGCLIENTID: Set MQTT client ID.
• AT+MQTTLONGUSERNAME: Set MQTT username.
• AT+MQTTLONGPASSWORD: Set MQTT password.
• AT+MQTTCONNCFG: Set configuration of MQTT connection.
• AT+MQTTALPN: Set MQTT Application Layer Protocol Negotiation (ALPN).
• AT+MQTTSNI: Set MQTT Server Name Indication (SNI).
• AT+MQTTCONN: Connect to MQTT Brokers.
• AT+MQTTPUB: Publish MQTT Messages in string.
• AT+MQTTPUBRAW: Publish long MQTT messages.
• AT+MQTTSUB: Subscribe to MQTT topics.
• AT+MQTTUNSUB: Unsubscribe from MQTT topics.
• AT+MQTTCLEAN: Close MQTT connections.

HTTP AT Commands

• AT+HTTPCLIENT: Send HTTP Client Request.
• AT+HTTPGETSIZE: Get HTTP Resource Size.
• AT+HTTPCGET: Get HTTP Resource.
• AT+HTTPCPOST: Post HTTP data of specified length.
• AT+HTTPCPUT: Put HTTP data of specified length.
• AT+HTTPURLCFG: Set/Get long HTTP URL.
• AT+HTTPCHEAD: Set/Query HTTP request headers.

User AT Commands

• AT+USERRAM: Operate user’s...

v3.2.0.0 Release Notes

v3.2.0.0 is released for ESP32 and ESP32-C3. The changes since the previous version are as follows.

• ESP32-AT
• ESP32C3-AT

ESP32-AT

Documentation for Release v3.2.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v3.2.0.0/esp32/index.html
ESP32-AT v3.2.0.0 is a major update for ESP32-AT v2.4.0.0.

The firmwares:

• ESP32-WROOM-32-AT-V3.2.0.0.zip
• ESP32-SOLO-AT-V3.2.0.0.zip
• ESP32-PICO-D4-AT-V3.2.0.0.zip
• ESP32-MINI-1-AT-V3.2.0.0.zip
• ESP-AT will not release firmwares for ESP32 WROVER series

This is the list of changes since release v2.4.0.0:

Breaking Changes

• esp-idf version updated to release/v5.0 (24b9d38a)
• AT+SYSFLASH: If you previously used v2.4.0.0 firmware and now directly flash v3.2.0.0 firmware, and MCU reads/writes parameters through AT+SYSFLASH command, the two versions will return different data, causing incompatibility (because v2.4.0.0 reads/writes parameters using partition method, while v3.2.0.0 uses NVS method). You can choose any of the following methods to resolve the compatibility issue:
  • Modify MCU code. For v2.4.0.0 firmware version, use AT+SYSFLASH command to read/write parameters; for v3.2.0.0 firmware version, use AT+SYSMFG command to read/write parameters.
  • Upgrade to v3.2.0.0 firmware using AT+USEROTA or AT+CIUPDATE command instead of directly flashing firmware.
  • Customize AT firmware. In the firmware released with v2.4.0.0, replace the esp-at.bin file with the esp-at.bin file from v3.1.0.0, and recompile it into a new 4MB firmware.
• AT+RFPOWER: The default value of ble tx power changed from 2 to 0

1. Feature

1.1 Wi-Fi

• AT+CWSTAPROTO and AT+CWAPPROTO commands added WIFI_PROTOCOL_LR support
• Added the AT+CWINIT command to init or deinit Wi-Fi
• AT+WEBSERVER: Wi-Fi provisioning supports special characters in SSIDs and passwords

1.2 TCP/IP

• Added the AT+CIPFWVER? command to query firmware versions
• AT+CIUPDATE: Added CDN network support
• Added the AT+TRANSINTVL command to support configurable intervals in passthrough mode

1.3 Application Layer

• Added the AT+MQTTLONGCLIENTID command to set MQTT client ID
• Added the AT+MQTTLONGUSERNAME command to set MQTT username
• Added the AT+MQTTLONGPASSWORD command to set MQTT password
• Added the AT+HTTPCHEAD commands to set more request headers
• Added AT+HTTPCPUT command to put HTTP data of specified length
• AT+HTTPGETSIZE: Added tx_size, rx_size, timeout parameters
• Added WebSocket AT commands
• AT+WEBSERVER: Added the customized partition upgrade function
• AT+CIPSNTPCFG: Added timezone query and timezone set when SNTP was disabled

1.4 System

• Added the AT+SYSMSGFILTER and AT+SYSMSGFILTERCFG commands to filter system messages
• Added the AT+USERWKMCUCFG and AT+USERMCUSLEEP commands to wake up MCU
• Added esp_at_get_para_as_float() API to get the float type parameter

1.5 Bluetooth

• AT+BLUFI: BluFi supports getting AP lists and sending custom data
• AT+BLEWL: Added ble whitelist command
• AT+BLUFINAME: Modified maximum length of BluFi name to 29 bytes
• AT+SAVETRANSLINK: Support Bluetooth LE passthrough mode
• AT+BLERDRSSI: Support reading the RSSI of Bluetooth LE connection
• Support sending exchange MTU requests when init server role

2. Bugfix

2.1 Wi-Fi

• Fixed that Wi-Fi mode was changed after waking up from deep sleep (AT+GSLP)
• Fixed that AT+CWQIF fails to disconnect the station if connected by multiple stations
• Fixed that AT+CWJAP returned the wrong reason code sometimes
• Fixed the crash caused by frequently enabling and disabling web server (AT+WEBSERVER)
• Fixed that Wi-Fi stopped reconnection if AT+BLUFI command was sent
• Fixed the issue of occasional network configuration failure in smartconfig (due to the lack of SSID validity check, which resulted in incorrect Wi-Fi auto-connection after power-up, further terminating the smartconfig network configuration).
• Fixed a potential issue that SoftAP could not work if powered down when saving the SoftAP configurations
• AT+CWJEAP: Fixed the issue that the EAP-TLS method does not work due to the last byte of PKI was not NULL terminated
• Fixed that AT+RFPOWER command could not set ble tx power when Wi-Fi mode was 0

2.2 TCP/IP

• Fixed that AT+CIPSTO could not work in passthrough mode
• Fixed that AT+CIPTCPOPT cannot work if AT works as a server
• Fixed that AT+CIPTCPOPT query command may return the wrong keep-alive value
• Added a workaround that AT+CIPCLOSE might block forever if ESP-AT works as a TCP client and SO_LINGER option is set (due to the LwIP SO_LINGER issue in some cases)
• Fixed that AT+CIPRECVDATA may cause a busy p issue
• Fixed that AT+CIPSSLCCONF, AT+CIPSSLCCN, AT+CIPSSLCSNI, AT+CIPSSLCALPN, AT+CIPSSLCPSK, AT+CIPTCPOPT returns multiple items in single connection
• Fixed a type and remote host parameter unmatched issue in AT+CIPSTART command
• Fixed a potential crash if the hostname length is bigger than 64 bytes in AT+CIPSTART command
• AT+CIPSEND: Fixed a data sent issue due to the changed link_id
• Fixed that AT+CIUPDATE returned ERROR if the OTA server returned too many OTA versions
• Fixed that AT+CIPSTART could not establish multiple UDP transmissions on the same port
• Fixed the issue of TLS connection failures caused by incorrect CN settings
• Fixed the issue of returning OK when setting AT+CIPSERVER twice

2.3 Application Layer

• Fixed that AT+HTTPURLCFG? returned the wrong URL
• Fixed that rx_size parameter could not work when set to 0 in AT+HTTPCGET command
• Fixed that AT+HTTPCPOST response returns the wrong command name if appended more post data
• Fixed the issue of AT blocking when MQTT broker actively closed MQTT client connection

2.4 System

• Fixed that busy p issue if an SSL connection was established and data was read in a weak network
• Fixed that GPIO32/GPIO33 could not work as UART pins due to conflict with the external 32 KHz crystal oscillator configuration
• Fixed that esp_at_port_write_data() crashed if input length < 0
• Fixed the high power consumption in light sleep if set the wake-up source
• Fixed the memory leak issue of AT+FS command
• SPI: Fixed a global issue where incorrect length was returned when reading data by SPI (For example, AT+HTTPCPOST command cannot read out all the data from SPI due to wanted data length being returned instead of the actual data length)

2.5 Bluetooth

• Fixed that device name was missing in adv packets
• Fixed some BluFi issues
• Fixed the issue of occasional restart caused by the AT+BLEGATTCPRIMSRV=0 command
• Fixed the ble tx power set fail issue

2.6 Tools

• Fixed that factory firmware cannot be generated on Windows OS
• build.py: Installed compilation environment depends on the target
• build.py: Used the python of esp-idf environment instead of external deprecated python
• at.py Support modifying manufacturing NVS

3. Optimization

• Refactored the storage mode of factory parameters to use the manufacturing NVS operation instead of partition operation. (see Why are we using manufacturing nvs way on the master? for more details)
• Simplified GitHub CI workflow
• Enabled power_management for the station when disconnected (Chip will do modem-sleep when rf module is not in use any more)
• Disable PMF to improve Wi-Fi compatibility when AT works in SoftAP mode
• Used Python to generate fatfs.bin instead of the deprecated mkfatfs component
• Support jihulab redirects in build.py
• Migrated AT firmware resources from download.espressif.com server to dl.espressif.com server
• Enhanced the documentation with the addition of more and detailed descriptions and addressed some document errors.

ESP32C3-AT

Documentation for Release v3.2.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v3.2.0.0/esp32c3/index.html
ESP32C3-AT v3.2.0.0 is a major update for ESP32C3-AT v2.4.2.0.

The firmwares:

• ESP32-C3-MINI-1-AT-V3.2.0.0.zip

This is the list of changes since release v2.4.2.0:

Breaking Changes

• esp-idf version updated to release/v5.0 (24b9d38a)
• AT+SYSFLASH: If you previously used v2.4.0.0 firmware and now directly flash v3.2.0.0 firmware, and MCU reads/writes parameters through AT+SYSFLASH command, the two versions will return different data, causing incompatibility (because v2.4.0.0 reads/writes parameters using partition method, while v3.2.0.0 uses NVS method). You can choose any of the following methods to resolve the compatibility issue:
  • Modify MCU code. For v2.4.0.0 firmware version, use AT+SYSFLASH command to read/write parameters; for v3.2.0.0 firmware version, use AT+SYSMFG command to read/write parameters.
  • Upgrade to v3.2.0.0 fir...

ESP32-C2 AT Release v3.1.0.0

Documentation for Release v3.1.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v3.1.0.0/esp32c2/index.html

ESP32-C2 AT v3.1.0.0 is a major update for ESP32C2-AT v3.0.0.0.

Changelog

This is the list of changes since release v3.0.0.0:

Breaking Changes

• AT+SYSFLASH: If you previously used v3.0.0.0 firmware and now directly flash v3.1.0.0 firmware with 2MB or 4MB, and MCU reads/writes parameters through AT+SYSFLASH command, the two versions will return different data, causing incompatibility (because v3.0.0.0 reads/writes parameters using partition method, while v3.1.0.0 uses NVS method). You can choose any of the following methods to resolve the compatibility issue:
  • Modify MCU code. For v3.0.0.0 firmware version, use AT+SYSFLASH command to read/write parameters; for v3.1.0.0 firmware version, use AT+SYSMFG command to read/write parameters.
  • Upgrade to v3.1.0.0 firmware using AT+USEROTA or AT+CIUPDATE command instead of directly flashing 2MB or 4MB firmware.
  • Customize AT firmware. In the firmware released with v3.0.0.0, replace the esp-at.bin file with the esp-at.bin file from v3.1.0.0, and recompile it into a new 2MB or 4MB firmware.

Known Issue

• Cannot set ble tx power.
• Wi-Fi and Bluetooth commands cannot be used at the same time due to lack of ram.
• The time obtained by SNTP will be reset to 1970 after the chip soft restart.

1. Feature

Basic AT Commands

• Added AT+RST setup command to enable the chip to enter firmware downloading mode.
• AT+SYSMSGFILTER: Enable or disable the system message filter.
• AT+SYSMSGFILTERCFG: Query/Set the system message filters.
• AT+SYSMFG: Query/Set manufacturing NVS User Partitions.
• Added AT+TRANSINTVL command to support configurable interval in passthrough mode.

Wi-Fi AT Commands

TCP/IP AT Commands

• AT+CIUPDATE supports CDN network

Bluetooth® Low Energy AT Commands (ESP32C2-4MB only)

The following commands are not supported in default ESP32C2-4MB firmware, but you can enable them according to guide.

• AT+BLEINIT: Bluetooth LE initialization.
• AT+BLEADDR: Query/Set Bluetooth LE device address.
• AT+BLENAME: Query/Set Bluetooth LE device name.
• AT+BLESCANPARAM: Query/Set parameters of Bluetooth LE scanning.
• AT+BLESCAN: Enable Bluetooth LE scanning.
• AT+BLESCANRSPDATA: Set Bluetooth LE scan response.
• AT+BLEADVPARAM: Query/Set parameters of Bluetooth LE advertising.
• AT+BLEADVDATA: Set Bluetooth LE advertising data.
• AT+BLEADVDATAEX: Automatically set Bluetooth LE advertising data.
• AT+BLEADVSTART: Start Bluetooth LE advertising.
• AT+BLEADVSTOP: Stop Bluetooth LE advertising.
• AT+BLECONN: Establish Bluetooth LE connection.
• AT+BLECONNPARAM: Query/Update parameters of Bluetooth LE connection.
• AT+BLEDISCONN: End Bluetooth LE connection.
• AT+BLECFGMTU: Set Bluetooth LE MTU length.
• AT+BLEGATTSSRV: GATTS discovers services.
• AT+BLEGATTSCHAR: GATTS discovers characteristics.
• AT+BLEGATTSNTFY: Notify a client of the value of a characteristic value from the server.
• AT+BLEGATTSIND: Indicate the characteristic value from the server to a client.
• AT+BLEGATTSSETATTR: GATTS sets characteristics.
• AT+BLEGATTCPRIMSRV: Generic Attributes Client (GATTC) discovers primary services.
• AT+BLEGATTCINCLSRV: GATTC discovers included services.
• AT+BLEGATTCCHAR: GATTC discovers characteristics.
• AT+BLEGATTCRD: GATTC reads characteristics.
• AT+BLEGATTCWR: GATTC writes characteristics.
• AT+BLESPPCFG: Query/Set Bluetooth LE SPP parameters.
• AT+BLESPP: Enter Bluetooth LE SPP mode.
• AT+BLESECPARAM: Query/Set Bluetooth LE encryption parameters.
• AT+BLEENC: Initiate Bluetooth LE encryption request.
• AT+BLEKEYREPLY: Reply the key value to the peer device.
• AT+BLECONFREPLY: Reply the confirm value to the peer device in the legacy connection stage.
• AT+BLEENCDEV: Query bonded Bluetooth LE encryption device list.
• AT+BLEENCCLEAR: Clear Bluetooth LE encryption device list.
• AT+BLESETKEY: Set Bluetooth LE static pair key.

MQTT AT Commands

HTTP AT Commands (ESP32C2-4MB only)

• AT+HTTPCHEAD: Set/Query HTTP request headers.

User AT Commands

WebSocket AT Commands

The following commands are not supported in default ESP32C2-4MB firmware, but you can enable them according to guide.

• AT+WSCFG: Set the WebSocket configuration.
• AT+WSOPEN: Query/Open a WebSocket connection.
• AT+WSSEND: Send data to a WebSocket connection.
• AT+WSCLOSE: Close a WebSocket connection.

2. Bugfix

Basic AT Commands

• Fixed the high power consumption if the wake-up was set.

Wi-Fi AT Commands

• Fixed that Wi-Fi could not auto-reconnect after AT+BLUFI command was sent.

TCP/IP AT Commands

• Fixed the potential crash if the hostname length was greater than or equal to 64 bytes.
• Fixed that UDP could not establish multiple connections on the same port.
• Fixed that TLS connection could not be established due to no SNI.
• Fixed the issue of returning OK when setting AT+CIPSERVER command for the second time with a different configuration.

Bluetooth® Low Energy AT Commands (ESP32C2-4MB only)

• Fixed that BluFi could not set the device name.
• Fixed that BluFi could not encrypt customer data.

MQTT AT Commands

• Fixed the memory leak when MQTT used a long client ID, username, or password.

User AT Commands

3. Optimization

• Provided more free heap size for users.
  • For 2MB flash size: free heap size increased from 83068 bytes to 98248 bytes. (About 15 KB)
  • For 4MB flash size: free heap size increased from 59628 bytes to 74964 bytes. (About 15 KB)
• Refactored the storage mode of factory parameters to use the manufacturing NVS operation instead of partition operation. (This optimization is compatible with previous firmware versions and does not affect the functionality after upgrading via OTA for users, except for the AT+SYSFLASH command.)
• Added the parameters validity check for AT+RFPOWER command.

ESP32-C2 AT Release v3.0.0.0

Documentation for Release v3.0.0.0 is available at https://docs.espressif.com/projects/esp-at/en/release-v3.0.0.0/esp32c2/index.html

The firmwares:

ESP32-C2-4MB_AT_Bin_V3.0.0.0.zip
ESP32-C2-2MB_AT_Bin_V3.0.0.0.zip

ESP32-C2 AT v3.0.0.0 is the first released version of AT firmware for ESP32-C2.

Feature

Basic AT Commands

• AT: Test AT startup.
• AT+RST: Restart a module.
• AT+GMR: Check version information.
• AT+CMD: List all AT commands and types supported in current firmware.
• AT+GSLP: Enter Deep-sleep mode.
• ATE: Configure AT commands echoing.
• AT+RESTORE: Restore factory default settings of the module.
• AT+UART_CUR: Current UART configuration, not saved in flash.
• AT+UART_DEF: Default UART configuration, saved in flash.
• AT+SLEEP: Set the sleep mode.
• AT+SYSRAM: Query current remaining heap size and minimum heap size.
• AT+SYSMSG: Query/Set System Prompt Information.
• AT+SYSFLASH: Query/Set User Partitions in Flash.
• AT+RFPOWER: Query/Set RF TX Power.
• AT+SYSROLLBACK: Roll back to the previous firmware. (ESP32C2-4MB only)
• AT+SYSTIMESTAMP: Query/Set local time stamp.
• AT+SYSLOG: Enable or disable the AT error code prompt.
• AT+SLEEPWKCFG: Query/Set the light-sleep wakeup source and awake GPIO.
• AT+SYSSTORE: Query/Set parameter store mode.
• AT+SYSREG: Read/write the register.

Wi-Fi AT Commands

• AT+CWMODE: Set the Wi-Fi mode (Station/SoftAP/Station+SoftAP).
• AT+CWSTATE: Query the Wi-Fi state and Wi-Fi information.
• AT+CWJAP: Connect to an AP.
• AT+CWRECONNCFG: Query/Set the Wi-Fi reconnecting configuration.
• AT+CWLAPOPT: Set the configuration for the command AT+CWLAP.
• AT+CWLAP: List available APs.
• AT+CWQAP: Disconnect from an AP.
• AT+CWSAP: Query/Set the configuration of an ESP SoftAP.
• AT+CWLIF: Obtain IP address of the station that connects to an ESP SoftAP.
• AT+CWQIF: Disconnect stations from an ESP SoftAP.
• AT+CWDHCP: Enable/disable DHCP.
• AT+CWDHCPS: Query/Set the IP addresses allocated by an ESP SoftAP DHCP server.
• AT+CWAUTOCONN: Connect to an AP automatically when powered on.
• AT+CWAPPROTO: Query/Set the 802.11 b/g/n protocol standard of SoftAP mode.
• AT+CWSTAPROTO: Query/Set the 802.11 b/g/n protocol standard of station mode.
• AT+CIPSTAMAC: Query/Set the MAC address of an ESP station.
• AT+CIPAPMAC: Query/Set the MAC address of an ESP SoftAP.
• AT+CIPSTA: Query/Set the IP address of an ESP station.
• AT+CIPAP: Query/Set the IP address of an ESP SoftAP.
• AT+CWSTARTSMART: Start SmartConfig.
• AT+CWSTOPSMART: Stop SmartConfig.
• AT+WPS: Enable the WPS function.
• AT+MDNS: Configure the mDNS function.
• AT+CWHOSTNAME: Query/Set the host name of an ESP station.
• AT+CWCOUNTRY: Query/Set the Wi-Fi Country Code.

TCP/IP AT Commands

• AT+CIPV6: Enable/disable the network of Internet Protocol Version 6 (IPv6).
• AT+CIPSTATUS: Obtain the TCP/UDP/SSL connection status and information.
• AT+CIPDOMAIN: Resolve a Domain Name.
• AT+CIPSTART: Establish TCP connection, UDP transmission, or SSL connection.
• AT+CIPSTARTEX: Establish TCP connection, UDP transmission, or SSL connection with an automatically assigned ID.
• [Passthrough Mode Only] +++: Exit the passthrough mode.
• AT+CIPSEND: Send data in the normal transmission mode or Wi-Fi passthrough mode.
• AT+CIPSENDL: Send long data in paraller in the normal transmission mode.
• AT+CIPSENDLCFG: Set the configuration for the command AT+CIPSENDL.
• AT+CIPSENDEX: Send data in the normal transmission mode in expanded ways.
• AT+CIPCLOSE: Close TCP/UDP/SSL connection.
• AT+CIFSR: Obtain the local IP address and MAC address.
• AT+CIPMUX: Enable/disable the multiple connections mode.
• AT+CIPSERVER: Delete/create a TCP/SSL server.
• AT+CIPSERVERMAXCONN: Query/Set the maximum connections allowed by a server.
• AT+CIPMODE: Query/Set the transmission mode.
• AT+SAVETRANSLINK: Set whether to enter Wi-Fi passthrough mode on power-up.
• AT+CIPSTO: Query/Set the local TCP Server Timeout.
• AT+CIPSNTPCFG: Query/Set the time zone and SNTP server.
• AT+CIPSNTPTIME: Query the SNTP time.
• AT+CIPSNTPINTV: Query/Set the SNTP time synchronization interval.
• AT+CIPFWVER: Query the existing AT firmware version on the server.
• AT+CIUPDATE: Upgrade the firmware through Wi-Fi.
• AT+CIPDINFO: Set “+IPD” message mode.
• AT+CIPSSLCCONF: Query/Set SSL clients.
• AT+CIPSSLCCN: Query/Set the Common Name of the SSL client.
• AT+CIPSSLCSNI: Query/Set SSL client Server Name Indication (SNI).
• AT+CIPSSLCALPN: Query/Set SSL client Application Layer Protocol Negotiation (ALPN).
• AT+CIPSSLCPSK: Query/Set SSL client Pre-shared Key (PSK).
• AT+CIPRECONNINTV: Query/Set the TCP/UDP/SSL reconnection interval for the Wi-Fi passthrough mode.
• AT+CIPRECVMODE: Query/Set socket receiving mode.
• AT+CIPRECVDATA: Obtain socket data in passive receiving mode.
• AT+CIPRECVLEN: Obtain socket data length in passive receiving mode.
• AT+PING: Ping the remote host.
• AT+CIPDNS: Query/Set DNS server information.
• AT+CIPTCPOPT: Query/Set the socket options.

Bluetooth® Low Energy AT Commands (ESP32C2-4MB only)

• AT+BLUFI: Start or Stop BluFi.
• AT+BLUFINAME: Query/Set BluFi device name.
• AT+BLUFISEND: Send user-customized data over BluFi.

MQTT AT Commands

• AT+MQTTUSERCFG: Set MQTT user configuration
• AT+MQTTLONGCLIENTID: Set MQTT client ID
• AT+MQTTLONGUSERNAME: Set MQTT username
• AT+MQTTLONGPASSWORD: Set MQTT password
• AT+MQTTCONNCFG: Set configuration of MQTT connection
• AT+MQTTALPN: Set MQTT Application Layer Protocol Negotiation (ALPN)
• AT+MQTTCONN: Connect to MQTT Brokers
• AT+MQTTPUB: Publish MQTT Messages in string
• AT+MQTTPUBRAW: Publish MQTT messages in binary
• AT+MQTTSUB: Subscribe to MQTT topics
• AT+MQTTUNSUB: Unsubscribe from MQTT topics
• AT+MQTTCLEAN: Close MQTT connections

HTTP AT Commands (ESP32C2-4MB only)

• AT+HTTPCLIENT: Send HTTP Client Request
• AT+HTTPGETSIZE: Get HTTP Resource Size
• AT+HTTPCGET: Get HTTP Resource
• AT+HTTPCPOST: Post HTTP data of specified length
• AT+HTTPCPUT: Put HTTP data of specified length
• AT+HTTPURLCFG: Set/Get long HTTP URL

User AT Commands

• AT+USERRAM: Operate user’s free RAM.
• AT+USEROTA: Upgrade the firmware according to the specified URL.
• AT+USERWKMCUCFG: Configure how AT wakes up MCU.
• AT+USERMCUSLEEP: MCU indicates its sleep state.
• AT+USERDOCS: Query the ESP-AT user guide for current firmware.