How to plug/unplug USB serial port programitically?
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How to plug/unplug USB serial port problematically? I am facing some strange issue with my USB serial port. I want to unplug and plug the USB Serial port Programitically, as i need to refresh the connection between system and hardware connected.Kindly help....... Thank in advance for the great programmers
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How to plug/unplug USB serial port problematically? I am facing some strange issue with my USB serial port. I want to unplug and plug the USB Serial port Programitically, as i need to refresh the connection between system and hardware connected.Kindly help....... Thank in advance for the great programmers
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How to plug/unplug USB serial port problematically? I am facing some strange issue with my USB serial port. I want to unplug and plug the USB Serial port Programitically, as i need to refresh the connection between system and hardware connected.Kindly help....... Thank in advance for the great programmers
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hi you can do this using the registry. set the DWORD of "Start" in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\{driver}\ to "4" for disable and 3 to enable. this may help :) never tested ^^
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I am looking for some one who did it problematically. But still thanks for your Solution :)
WTF is 'problematically'? I did it while using a problem?
Check out the CodeProject forum Guidelines[^] The original soapbox 1.0 is back![^]
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WTF is 'problematically'? I did it while using a problem?
Check out the CodeProject forum Guidelines[^] The original soapbox 1.0 is back![^]
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I am looking for some one who did it problematically. But still thanks for your Solution :)
whats the exactly problem you have with usb plugged devices ? i may can help you out, i wrote a serial component in c# that checks wheather the connection needs to be closed after unplugging the device and reopend after replug the device to usb without running into exceptions..
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whats the exactly problem you have with usb plugged devices ? i may can help you out, i wrote a serial component in c# that checks wheather the connection needs to be closed after unplugging the device and reopend after replug the device to usb without running into exceptions..
I have connected the usb serial port and started getting the data from the hardware. Suddenly i will stop the hardware and re run it .Now the problem is when i return the hardware and try to re connect the my application back and try to connect the COM port, it throws me a message the port is already connected and because of this i can not receive the data, kindly help me to understand the stuff
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I have connected the usb serial port and started getting the data from the hardware. Suddenly i will stop the hardware and re run it .Now the problem is when i return the hardware and try to re connect the my application back and try to connect the COM port, it throws me a message the port is already connected and because of this i can not receive the data, kindly help me to understand the stuff
If you kill the hardware, the classes relating to the serial comms have probably bombed, and your application itself is holding the serial port resource on one of its async threads. I have seen this while programming to a usb/serial device (resol solar controller). When you exit the application the lock is released and then when you start the app again all is fine. You should check that when you kill the external hardware or pull the connection, the necessary exceptions are being caught and the serial connection is closed gracefully to ensure all resource locks are released.
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I have connected the usb serial port and started getting the data from the hardware. Suddenly i will stop the hardware and re run it .Now the problem is when i return the hardware and try to re connect the my application back and try to connect the COM port, it throws me a message the port is already connected and because of this i can not receive the data, kindly help me to understand the stuff
and it may be wise to call DiscardInBuffer() and DiscardOutBuffer() right after creating your serial port, and before connecting any event handlers to it. :)
Luc Pattyn
I only read code that is properly indented, and rendered in a non-proportional font; hint: use PRE tags in forum messages
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If you kill the hardware, the classes relating to the serial comms have probably bombed, and your application itself is holding the serial port resource on one of its async threads. I have seen this while programming to a usb/serial device (resol solar controller). When you exit the application the lock is released and then when you start the app again all is fine. You should check that when you kill the external hardware or pull the connection, the necessary exceptions are being caught and the serial connection is closed gracefully to ensure all resource locks are released.
The problem is that the stream in the SerialPort class will not be closed if the external hardware will be removed. this is an bug in the framework. to prevent this behaviour the solution is to rewrite a serial port class using unmanaged code or to kill the application like daveauld described above.. serial port communication was not designed to work during the hardware will be removed. in ealy cases this was not possible because the COM was an integrated hardware in the pc not an usb plugalbe device. i had the same problem and sovled it by rewriting the serial port (internal catching read/write errors and than closing and reopening the filestream on COM). bless :)