The first parameter is the port name as a string, usually COM1: or COM2:, but in theory the name could be anything, so I have used a string rather than a number.

• 第一个参数是端口的名称作为一个字符串，通常称作COM1：或COM2：，但在理论上的名称可能是任意，所以我用一个字符串，而不是一个数字。