Misdirection. Sometimes it's not actually a .NET problem:
If you're using Mono's
System.IO.Ports.SerialPort on Linux,
and you're getting the
argument", it might not actually be the class library
implementation. Check your serial adapter (assuming you're
using a USB-to-serial adapter...) I'm using an adapter with
the MosChip 7720 chipset:
usbcore: registered new interface driver usbserial USB Serial support registered for generic usbcore: registered new interface driver usbserial_generic usbserial: USB Serial Driver core USB Serial support registered for Moschip 2 port adapter mos7720: 220.127.116.11F:Moschip USB Serial Driver moschip7720 2-1:1.0: Moschip 2 port adapter converter detected usb 2-1: Moschip 2 port adapter converter now attached to ttyUSB0 usb 2-1: Moschip 2 port adapter converter now attached to ttyUSB1 usbcore: registered new interface driver moschip7720
When opening the serial port,
System.IO.Ports.SerialPort indirectly calls
SetSignal, which calls the
which, as it happens, ISN'T IMPLEMENTED in the
mos7720 driver! Harumph.
There's a patch, signed off by both Alan Cox and Greg Kroah-Hartman, but it doesn't seem to be in the upstream, yet.