How to Use Arduino as USB to Serial Converter | Microcontroller Tutorials
Amazon.com: WITMOTION USB-UART 6-in-1 USB to Serial Converter, Multifunctional (USB to TTL/RS485/232, TTL-RS232/485, 232 to 485), Universal Adapter Module with CP2102 Compatible with Windows 7/8/10,Linux, Arduino : Electronics
Arduino as a usb to serial(TTL) converter - YouTube