ESP8266 AT-command parser

This ESP8266 AT-command parser is platform-independent, minimal implementation for building application-specific network projects , which connect with old ESP8266 wifi modules (not like NodeMCU ESP device) and resource-constraint embedded devices like host MCU boards.

Table of Content

• Issues about versions of the AT firmware
• AT commands available
• Tests
• Quick Start

Issues about versions of the AT firmware ...

If you program the latest version (v1.7.x) of AT firmware to the ESP device, there would be more new AT commands supported on the device, however it is not that every new AT command always works as expected, also the AT firmware requires more than 512KB flash memory space since the version v1.7.0 was released, that means you are NOT allowed to use the latest AT firmware on some old ESP8266 devices (e.g. ESP-01). Therefore I don't implement all of the existing AT commands at here, I also choose the stable version (v1.6.0) of AT firmware instead, which can work with all types of ESP8266 devices.

AT commands available.

Here is the list of AT-commands available in this repository.

AT+RST	AT+GMR	ATE0 / ATE1	AT+CIPSTA
AT+RESTORE	AT+CWMODE	AT+CIPSTATUS	AT+CIPAP
AT+CWJAP	AT+CWLAP	AT+CWQAP	AT+CIPSTATUS
AT+CIPSTART	AT+CIPCLOSE	AT+CIPSEND	AT+CIFSR
AT+CIPMUX	AT+CIPSERVER	AT+CIPSTO	AT+CIPMODE
AT+PING	AT+CIPDINFO	AT+GSLP

Tests

There are 3 test cases in this repository, these tests start after your ESP device switches to station mode and successfully connects to available AP.

test name	what it does
ping	ping a specific host
http_server	turn on server mode, demonstrate basic capability of HTTP/1.1 handshaking process.
mqtt_client	start TCP connection, demonstrate publishing/subscribing capability of MQTT v5.0 handshaking process.

Note that :

• For the test http_server, you can send HTTP requests to the test server running on the ESP device, by using web browsers, related commands like wget, or other debugging tools.
• For the test mqtt_client, you need to run MQTT broker (server) & subscribing software on other devices in order to interact with this test MQTT client. (In my case, I run Mosquitto MQTT broker and Paho.MQTT.C subscriber seperately on 2 of my Raspberry PIs)

Quick Start

1. Ensure to add following essential defined macros :

   • ESP_CFG_SYS_PORT in your configuration header file, ESP_CFG_SYS_PORT can be the default platform ESP_SYS_PORT_FREERTOS or any other platform you work with, please refer to developer guide .
   • The type of your ESP8266 device, so far this ESP AT-command parser has been verified with ESP-01s and ESP-12s modules. Please add macro ESP_CFG_DEV_ESP01 or ESP_CFG_DEV_ESP12, accroding to the ESP device you work with.

2. For building test images, you have :

make INTEGRATION_TEST=yes TESTNAME=<test_name> OS_NAME=<os_name>  PLATFORM=<hw_platform_name>

where :

• <os_name> : So far this ESP AT-command parser is implemented only on FreeRTOS and STM32 platform, the default value of this is FreeRTOS. For anyone who is willing to port for other Operating Systems / platforms, please refer to developer guide
• <hw_platform_name> : so far this ESP parser is verified with STM32F4xx board, (ARM Cortex-M4 MCU platform), the default value is "STM32F4", For anyone who is willing to port for other platforms that haven't been implemented at here, please refer to developer guide
• <test_name> can be ping, http_server, or mqtt_client

3. For debugging tool, it is optional to use OpenOCD / gdb-multiarch, build latest version of OpenOCD from source, then run the command below :

make dbg_server OPENOCD_HOME=/PATH/TO/YOUR_OPENOCD

and

make dbg_client