Appendix B Watchdog Timer on WinCE

There is a built-in Watchdog timer on Windows CE 5.0 for TPC-1070. You can access it through WIN32 API. TPC-1070 provides a WDT driver to allow users to enable/disable the Watchdog timer. The driver name is “WDT1:”. Programmers must open this driver before using the resources. Then programmers can use DeviceIOControl functions to enable/disable Watchdog timer. The introduction below includes the DeviceIOControl, the definition of the parameter and an example.

B.1 DeviceIOControl

This function sends a control code directly to a specified device driver, causing the corresponding device to perform the specified operation.

BOOL DeviceIoControl(

HANDLE hDevice,

DWORD dwIoControlCode,

LPVOID lpInBuffer,

DWORD nInBufferSize,

LPVOID lpOutBuffer,

DWORD nOutBufferSize,

LPDWORD lpBytesReturned,

LPOVERLAPPED lpOverlapped );

Parameters:

hDevice

[in] Handle to the device that is to perform the operation. Call the Create- File function to obtain a device handle.

dwIoControlCode

[in] Specifies the control code for the operation. This value identifies the specific operation to be performed and the type of device on which the operation is to be performed. No specific values are defined for the dwIo- ControlCode parameter. However, the writer of a custom device driver can define IOCTL_XXXX control codes, per the CTL_CODE macro. These

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Intel TPC-1070 user manual Appendix B Watchdog Timer on WinCE, DeviceIOControl