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## Direct Framebuffer Access

In order to allow both direct framebuffer access and hardware accelerator access, contention for video memory between the application program and the hardware accelerator must be properly handled. This is provided by the EnableDirectAccess and DisableDirectAccess functions. If the EnableDirectAccess function pointer is not NULL, then you must call these functions prior to performing any direct access to the framebuffer via either the banked framebuffer or the linear framebuffer, and then call DisableDirectAccess before calling any other hardware accelerator functions again.

If the EnableDirectAccess function is NULL, you must instead call the WaitTillIdle function to ensure the hardware has completed the last drawing operation before accessing the framebuffer directly. You need not call any other functions to return to accelerated rendering again.

When the video mode is first initialized, the hardware is automatically set up for hardware accelerated rendering, as though DisableDirectAccess was called immediately after setting the display mode.

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