On 2010-11-27 08:55, Dena Meier wrote:
> I think I may have figured it out.
>

And exactly 'what* did you "figure out" ?
And why not tell us ? Is it secret in some way ?


> Does anyone know if there are serious issues regarding using
> C# .NET System.IO.Ports.SerialPort object?
>

If you are sending data as "strings", note that SerialPort
does default encoding of any charachetrs outside of (higher
then) the lowest (0-127) ASCII codes ! For ASCII codes in
the range 127-255 there is a default Unicode encoding done.
To have the Unicode-encoding as the *default* is a major
brain-fart, if you ask me.

To send full 8-bit values you have to either set the "encoding"
property of the SerielPost object to some encoding that does
not change the upper half of the 8-bit characters, *or* send
arrays of bytes (they will never, as far as I understand be
encoded or changes by SerialPort).

A few minutes Googling on "SerialPort encoding 8-bit" or
similar will quickly give you some example, such as :

http://www.visualstudiodev.com/visual-basic-express-edition/serial-port--se=
nding-8-bit-problem-39369.shtml


What that what you "figured out" ?

And you are correct in that the (old) file-based API's
in WIn32 does not do this.


> I have discovered that when I wrote a test program using
> Win32 API CreateFile, WriteFile, and ReadFile on the
> COM4 USB port (the port that is the PIC18LF2450) that
> this works fine for both sending and receiving.
> So Hyperterm is not using .NET SerialPort.
> Hyperterm is probably using the old Win32 API calls, or
> using an object that directly calls Win32 for serial access.
>
> So now I have to figure out a way to access a serial port
> in C# .NET without using the SerialPort object!!
>

Or simply use SerialPort with an encoding that is
"transparent" *or* send "bytes" instead of "strings".



> There must be a bug in .NET SerialPort.

Depends on what you "figured out"... :-)


>
> Any ideas on this are welcome.
>
> Thank You,
> Dena Meier
>
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