Supports USB to 2-ch UART, or USB to 1-ch UART + 1-ch I2C + 1-ch SPI, or USB to 1-ch UART + 1-ch JTAG Supports 2-ch high-speed UART interfaces, up to 9Mbps baud rate, with CTS and RTS hardware automatic flow control Supports 1-ch I2C interface, for easy operating EEPROM through the host computer or programming I2C devices such as OLED and sensor Supports 1-ch SPI interface, with 2x chip select signal pins, capable of controlling 2-ch SPI slave devices at different times   Onboard 3.3V and 5V level conversion circuit for switching the operating level of the communication interface, better compatibility Onboard resettable fuse and ESD protection circuit, provides over-current/over-voltage proof, safe and stable communication Aluminium alloy case with oxidation dull-polish surface, CNC process opening, solid and durable, well-crafted High-quality USB-B and DC connectors, smooth plug & pull, durable and reliable, with anti-reverse protection