Controlling COM ports

Question

Hello all I have an embedded PC with 8 serial ports. (COM1 through COM8). The application running on this PC defaults to COM1 and you cannot change that. I need to look at data on the other ports. In other words I need to tell the embedded PC that COM 4 is COM1. I have been doing this with a VB program that I wrote calling batch files using a Change Port command for example if I want to look at the data on COM 5 the VB program runs a batch file containing a [chgport COM1=COM5]. When I need to look at data on COM1 the VB program runs a batch file with [chgport /D COM1]. The above is not working very well. It does work but is not reliable. Is there a method within C# to redirect the serial ports? Again the application running on the embedded PC (OS is XPE) will only look at COM1 so I have to redirect the data from another port to COM1. Thank you in advance for your time and help.

Alan · Answer

You should be able to view the output by redirecting it to a file (ports.txt say). Just change the 'args' line to this: string args = /C  + fileName +  /QUERY >ports.txt;

kyle · Answer

Hi Alan I was unable to view the port query when I ran the code that you posted. Any suggestions?

kyle · Answer

Hi Alan I will give this a try. Thank you for your help.

Alan · Answer

To my knowledge there's nothing in the SerialPort class or elsewhere in the compact framework that would enable you to remap the COM ports. Rather than use a batch file have you tried to call chgport directly using the System.Diagnostics.Process class? The following worked OK when I tried it just now: using System; using System.Diagnostics; class Test { static void Main() { string fileName = @c:\windows\system32\dllcache\chgport.exe; string args = /C  + fileName +  /QUERY; Process.Start(cmd.exe args); } }