VC_WriteIOMemoryBYTE(p, b)
The VC_WriteIOMemoryBYTE macro writes a single byte into a device’s mapped I/O memory space.
None.
Kernel-mode video capture drivers typically use the VC_WriteIOMemoryBYTE macro to write into a location within the frame buffer. Drivers can obtain the frame buffer’s base address by calling VC_GetFrameBuffer.
Using the VC_WriteIOMemoryBYTE macro to write into I/O space helps ensure driver portability across system platforms.