VC_ReadIOMemoryBlock

VC_ReadIOMemoryBlock(dst, src, cnt)

The VC_ReadIOMemoryBlock macro reads a specified number of bytes from a device’s mapped I/O memory space into system memory space.

Parameters

dst

Pointer to a buffer to receive data copied from mapped I/O space.

src

Address of the first mapped I/O memory location from which data is to be copied.

cnt

Number of bytes to be copied from I/O space.

Return Value

None.

Comments

Kernel-mode video capture drivers typically use the VC_ReadIOMemoryBlock macro to read a block of memory within the frame buffer. Drivers can obtain the frame buffer’s base address by calling VC_GetFrameBuffer.

Using the VC_ReadIOMemoryBlock macro to read I/O space helps ensure driver portability across system platforms.