@SERIALPORTOPEN[COMn[, baud[, parity[, bits[, stopbits[, flow]]]]]] - Open a serial port for read & write. The parameters are:
COMn - The COM port to open (COM1 - COM9)
baud - The baud rate (110 - 256000)
parity - The parity scheme to use. This can be one of the following values:
bits - The number of bits in the bytes to transmit & receive
stopbits - The number of stop bits to be used. This can be one of the following values:
flow - The type of flow control to use. This can be one of the following values:
@SERIALPORTOPEN returns a handle to the serial port, which must be passed to the other serial port functions.