Johnson峰的部落格

問題：電腦Com PORT連接GPS對時信號，電腦上有一個程式，從Com口讀取GPS時間信號，然後設置電腦本地時間;但問題是程式打開Com口一直失敗，報Com已經被佔用， 不能再次打開Com，奇怪Com怎麼會被佔用呢？

問題原因：原來Com連接的GPS設備，因為滿足了微軟對Serial ballpoint設備的檢測要求，被微軟誤認為Com連接的是Serial ballpoint設備，作業系統佔用了Com導致問題。

解決辦法1：

在設置管理器-滑鼠及其他指標裝置：禁用:Microsoft Serial BallPoint，這樣就防止Com連接的設備誤檢測為Microsoft Serial BallPoint設備

解決方法2：（來至於網上，未測試）

I had the same problem, cursor sometimes jumps all over the screen  

 Here's the fix:  Open Regedit. Navigate to
      HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SerMouse, and change the value "Start" from 3 to 4.  Reboot.

I found this on a website for a program to help with gps . Worked like a charm for me.

There is a reg file that will do the editing for you also.  http://www.curioustech.net/downloads/reg.zip  註冊表

解決方法3：（來至於網上，未測試）

running the command "DEVCON.exe DISABLE *PNP0F09"

It seems to work on W7 as well. You may try this solution by getting hold of DEVCON.EXE: It is included in the Windows DDK (Driver Development Kit 7.1). Or you may download it from here, I believe: http://support.microsoft.com/kb/311272
EDIT: Seems like it works, but it has to be done for each separate USB port you will be using. I am working on trying to find a solution to this...

參考網頁：

http://www.biosren.com/viewthread.php?tid=1004

http://www.gpsoz.com.au/jumping_mouse.htm

http://answers.microsoft.com/en-us/windows/forum/w...

參考網頁：

http://blog.csdn.net/lizheng308/article/details/68...