A simple converter can be sourced online, but the only thing he could find locally that was even close was a USB to RS-232 converter. He used that component to craft his own USB to RS-485 bridge.

嵌入式里面说的串口，一般是指UART口，但是我们经常搞不清楚它和COM口的区别, 以及RS232, TTL等关系, 实际上UART,COM指的物理接口形式 (硬件), 而TTL、RS-232是指的电平标准 (电信号).