# COMMU [中文](/zh_CN/product_documents/modules/module_commu) | English | [日本語](ja/product_documents/modules/module_commu) ## DESCRIPTION COMMU is a communication interface converter which can meet most of the application design. Now, COMMU owns two I2C interfaces, one CAN interface and one RS485 interface. Simultaneously, COMMU also owns a TTL level interface. It means you just need to stack it underneath M5Core when you want to control a CAN device or RS485 device. Be care about TTL Interface. It is a UART Interface actually by default. But you can switch it to connect with UART2 after changed those jumpers(J6, J7, J9, J10). ## FEATURES - 2x I2C Interface - 1x CAN Interface - 1x RS485 Interface - 1x TTL Interface ## INCLUDES - 1x M5Stack COMMU Module ## PinMap | *CAN* | *ESP32 Chip* | | :----------: |:------------: | | CAN_CS | GPIO12 | | CAN_INT | GPIO15 | | CAN_SCK | GPIO18 | | CAN_MISO | GPIO19 | | CAN_MOSI | GPIO23 | | *I2C Interface* | *ESP32 Chip* | | :--------------: |:------------: | | IIC_SDA | GPIO21 | | IIC_SCL | GPIO22 | ## DOCUMENTS - **[Schematic](https://github.com/m5stack/M5-Schematic/blob/master/Modules/COMMU.pdf)** - **[Purchase](https://www.aliexpress.com/store/product/M5Stack-New-COMMU-Module-Extend-RS485-TTL-CAN-I2C-Port-with-MCP2515-TJA1051-SP3485-Development-Board/3226069_32954475633.html?spm=a2g1y.12024536.productList_5885013.subject_2)**