how can I reset COM Port.
in [Win32 Kernel]
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From: wangzhong on 24 Oct 2005 03:35 Hello. I have written a modem comunication app and got a very strange problem. When CE_RXPARITY error is catched by my app, I use ClearCommError() to reset this error. but COM access become abnormally since this connntion. My app only can get the first telegram from any connection. It is failed to repair this problem that I tried to reopen the serial port, But if I close my app, then I reopen it, the com port become normally. I use CreateFile() to open serial port, CloseHandle() to close serial port. Why can I didn't get the same result as application restart. Any help would be greatly appreciated. --------------------------- wz
From: Arkady Frenkel on 24 Oct 2005 12:14 Try to use devcon from DDK to check port status and disable/enable the port Arkady "wangzhong" <wzhy2000(a)hotmail.com> wrote in message news:eQe%23e1G2FHA.2964(a)TK2MSFTNGP09.phx.gbl... > Hello. > > I have written a modem comunication app and got a very strange problem. > > When CE_RXPARITY error is catched by my app, I use ClearCommError() > to reset this error. but COM access become abnormally since this > connntion. > My app only can get the first telegram from any connection. > > It is failed to repair this problem that I tried to reopen the serial > port, > But if I close my app, then I reopen it, the com port become normally. > > I use CreateFile() to open serial port, CloseHandle() to close serial > port. > Why can I didn't get the same result as application restart. > > Any help would be greatly appreciated. > > --------------------------- > wz > >
From: Arkady Frenkel on 26 Oct 2005 12:28 Additionally : good one is restart command of devcon Arkady "Arkady Frenkel" <arkadyf(a)hotmailxdotx.com> wrote in message news:OCMkFYL2FHA.464(a)TK2MSFTNGP15.phx.gbl... > Try to use devcon from DDK to check port status and disable/enable the > port > Arkady > > "wangzhong" <wzhy2000(a)hotmail.com> wrote in message > news:eQe%23e1G2FHA.2964(a)TK2MSFTNGP09.phx.gbl... >> Hello. >> >> I have written a modem comunication app and got a very strange problem. >> >> When CE_RXPARITY error is catched by my app, I use ClearCommError() >> to reset this error. but COM access become abnormally since this >> connntion. >> My app only can get the first telegram from any connection. >> >> It is failed to repair this problem that I tried to reopen the serial >> port, >> But if I close my app, then I reopen it, the com port become normally. >> >> I use CreateFile() to open serial port, CloseHandle() to close serial >> port. >> Why can I didn't get the same result as application restart. >> >> Any help would be greatly appreciated. >> >> --------------------------- >> wz >> >> > >
From: wangzhong on 27 Oct 2005 01:27 I will try to do it, thank you very much. "Arkady Frenkel" <arkadyf(a)hotmailxdotx.com> wrote in message news:e5jYeok2FHA.2816(a)tk2msftngp13.phx.gbl... > Additionally : good one is restart command of devcon > Arkady > > "Arkady Frenkel" <arkadyf(a)hotmailxdotx.com> wrote in message > news:OCMkFYL2FHA.464(a)TK2MSFTNGP15.phx.gbl... > > Try to use devcon from DDK to check port status and disable/enable the > > port > > Arkady > > > > "wangzhong" <wzhy2000(a)hotmail.com> wrote in message > > news:eQe%23e1G2FHA.2964(a)TK2MSFTNGP09.phx.gbl... > >> Hello. > >> > >> I have written a modem comunication app and got a very strange problem. > >> > >> When CE_RXPARITY error is catched by my app, I use ClearCommError() > >> to reset this error. but COM access become abnormally since this > >> connntion. > >> My app only can get the first telegram from any connection. > >> > >> It is failed to repair this problem that I tried to reopen the serial > >> port, > >> But if I close my app, then I reopen it, the com port become normally. > >> > >> I use CreateFile() to open serial port, CloseHandle() to close serial > >> port. > >> Why can I didn't get the same result as application restart. > >> > >> Any help would be greatly appreciated. > >> > >> --------------------------- > >> wz > >> > >> > > > > > >
From: wangzhong on 1 Nov 2005 10:12
sorry, It did not work. I want to know the difference between the app restart and the com restart about serial port initializtion ------or------ When COM port is opened first in a process, what is done for COM initializtion in Windows kernel ? "wangzhong" <wzhy2000(a)hotmail.com> wrote in message news:O7qk6br2FHA.700(a)TK2MSFTNGP15.phx.gbl... > I will try to do it, thank you very much. > > "Arkady Frenkel" <arkadyf(a)hotmailxdotx.com> wrote in message > news:e5jYeok2FHA.2816(a)tk2msftngp13.phx.gbl... > > Additionally : good one is restart command of devcon > > Arkady > > > > "Arkady Frenkel" <arkadyf(a)hotmailxdotx.com> wrote in message > > news:OCMkFYL2FHA.464(a)TK2MSFTNGP15.phx.gbl... > > > Try to use devcon from DDK to check port status and disable/enable the > > > port > > > Arkady > > > > > > "wangzhong" <wzhy2000(a)hotmail.com> wrote in message > > > news:eQe%23e1G2FHA.2964(a)TK2MSFTNGP09.phx.gbl... > > >> Hello. > > >> > > >> I have written a modem comunication app and got a very strange problem. > > >> > > >> When CE_RXPARITY error is catched by my app, I use ClearCommError() > > >> to reset this error. but COM access become abnormally since this > > >> connntion. > > >> My app only can get the first telegram from any connection. > > >> > > >> It is failed to repair this problem that I tried to reopen the serial > > >> port, > > >> But if I close my app, then I reopen it, the com port become normally. > > >> > > >> I use CreateFile() to open serial port, CloseHandle() to close serial > > >> port. > > >> Why can I didn't get the same result as application restart. > > >> > > >> Any help would be greatly appreciated. > > >> > > >> --------------------------- > > >> wz > > >> > > >> > > > > > > > > > > > |