How to Add a New Platform

Since the esp-at project supports different platform, for example, ESP32 UART AT, ESP32 SDIO AT, even supports ESP8266 AT, when compiling the esp-at project, users can set different configurations to generate AT firmware for different ESP modules. The detailed information are in the esp-at/module_config directory. Default configuration is the “PLATFORM_ESP32” for ESP-WROOM-32.Please note that if you use a different bus (for example, SDIO, SPI or other buses) instead of UART, then you cannot use the default module_espxxxx_default directly, you need to re-configure it in the menuconfig.Herein, we provide an example of the ESP32 SDIO AT to show how to set a new platform for the esp-at project.

1. Create a New Platform

For example, to name the platform as “PLATFORM_ESP32”, the module as “WROOM32-SDIO”, we need to open the components/customized_partitions/raw_data/factory_param/factory_param_data.csv and add a new row of the new platform at the end.

platform	module_name	magic_flag	version	module_id	tx_max_power	start_channel	channel_num	country_code	uart_baudrate	uart_tx_pin	uart_rx_pin	uart_ctx_pin	uart_rts_pin	tx_control_pin	rx_control_pin
-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-	-xxx-
PLATFORM_ESP32	ESP32-SDIO	0xfcfc	1	1	1	1	13	CN	-1	-1	-1	-1	-1	-1	-1

2. Set Makefile

Open the Makefile and set to the new platform. Please use capital letters.

export ESP_AT_PROJECT_PLATFORM ?= PLATFORM_ESP32
export ESP_AT_MODULE_NAME ?= ESP32-SDIO

3. Configure the New Platform

• 3.1. Enter module_config folder, copy the module_esp32_default to make a new module_esp32-sdio.

• 3.2. In this example, we need not to change the partition table and the ESP-IDF version, so the at_customize.csv, IDF_VERSION and partitions_at.csv all need not to be changed.

• 3.3. Revise the sdkconfig.defaults

  • Configure to use the partition table in the module_esp32-sdio folder, revise the following items：

  CONFIG_PARTITION_TABLE_CUSTOM_FILENAME="module_config/module_esp32-sdio/partitions_at.csv"
  
  CONFIG_PARTITION_TABLE_FILENAME="module_config/module_esp32-sdio/partitions_at.csv"
  
  CONFIG_AT_CUSTOMIZED_PARTITION_TABLE_FILE="module_config/module_esp32-sdio/at_customize.csv"
  

  • Since the esp-at project already supports the SDIO configuration, we only need to add it into the sdkconfig.defaults.

    • Remove the UART AT configuration in the sdkconfig.defaults.

    CONFIG_AT_BASE_ON_UART=y
    CONFIG_AT_UART_PORT=1
    CONFIG_AT_UART_PORT_RX_PIN=16
    CONFIG_AT_UART_PORT_TX_PIN=17
    CONFIG_AT_UART_PORT_RTS_PIN=14
    CONFIG_AT_UART_PORT_CTS_PIN=15
    

    And add the following configuration.

    CONFIG_AT_BASE_ON_SDIO=y
    

4. Revise the at_core lib

Since the ESP32 SDIO AT and the ESP32 UART AT are based on the same platform, ESP32, they will share the same at_core.lib. In this case, we need not to add any new at_core lib.If you need to use a new at_core lib, put the lib into the components/at/lib, rename the lib as libxxxx_at_core.a, xxxx is the platform name. For example, if you set the ESP_AT_PROJECT_PLATFORM ?= PLATFORM_ESP8848 in the Makefile in Step 2, then the lib should be named as libesp8848_at_core.a.