Windows CE 触摸屏(TouchPanel)驱动简析(2)-DDSI函数
1.DdsiTouchPanelAttach和DdsiTouchPanelDetach
DLL entry进入或结束执行,这里不需要任何工作,直接返回0
LONG DdsiTouchPanelAttach(void)
{
return 1;
} This function executes when the MDD's DLL entry point gets a DLL_PROCESS_ATTACH message.
LONG DdsiTouchPanelDetach(void)
{
return 0;
}
This function executes when the MDD's DLL entry point receives a DLL_PROCESS_DETACH message.
2.DdsiTouchPanelEnable
DdsiTouchPanelEnable使能触摸屏并进行相应的初始化工作等。
3.DdsiTouchPanelDisable
对应的就有DdsiTouchPanelDisable函数,将DdsiTouchPanelEnable申请的资源进行释放.屏蔽中断.
4.DdsiTouchPanelSetMode
DdsiTouchPanelSetMode用来设置触摸屏的采样率周期.函数传入TPSM_SAMPLERATE_LOW_ID或TPSM_SAMPLERATE_HIGH_ID来进行相应的设置.这里只有一个采样率周期,所以函数不做实际工作.
5.DdsiTouchPanelPowerHandler
DdsiTouchPanelPowerHandler用来通知驱动系统正进入或离开挂起状态.
参数bOff为TRUE表明系统正在关闭, FALSE表明系统正在开启.
6.DdsiTouchPanelGetDeviceCaps
DdsiTouchPanelGetDeviceCaps用来查询触摸屏设备的性能参数.
iIndex可能为以下3个参数:
TPDC_SAMPLE_RATE_ID: 返回采样周期,这里TSP_SAMPLE_RATE_LOW,TSP_SAMPLE_RATE_HIGH,
TPDC_CALIBRATION_POINT_ID:返回需要校准点的XY坐标.校准点坐标索引在PointNumber(lpOutput传递的结构成员).调用
7.DdsiTouchPanelGetPoint来获得.这点分别位于四个角和中间,也就是我们调用触摸屏校准程序时会调用到的函数.
TPDC_CALIBRATION_POINT_COUNT_ID:返回用来校准触摸屏的校准点数目.这里的数目设置为5.
8. DdsiTouchPanelPowerHandler
As with all power-down handlers, this function cannot call functions in
other DLLs, memory allocators, debugging output functions, or do anything
that could cause a page fault. This routine is called by the MDD.
9. DdsiTouchPanelSetMode
This function sets information about the touch screen device.
DEF:
LIBRARY touch
LIBRARY touch
EXPORTS
TouchPanelGetDeviceCaps
TouchPanelEnable
TouchPanelDisable
TouchPanelSetMode
TouchPanelReadCalibrationPoint
TouchPanelReadCalibrationAbort
TouchPanelSetCalibration
TouchPanelCalibrateAPoint
TouchPanelPowerHandler