This register has one bit for every layer
that indicates whether a layer is enabled (1) or disabled (0). Bit[0] is for the master input
layer, which associates with the s_axis_video
AXI4-Stream input. This is the bottom-most layer, and all other
layers are blended on top. If this layer is disabled and no other layers are blended on top,
the background color as specified by the previous mentioned registers are shown. If this layer
is enabled, video data should be sent to this layer, otherwise the Video Mixer stalls.
Bit[1] is for overlay layer 1, which associates with either
s_axis_video1
AXI4-Stream input or m_axi_mm_video1 memory mapped AXI4 input, depending on the Interface
Type field selected in the Vivado IDE. Bit[2] is for
overlay layer 2 and so on, until Bit[16] which enables/disables layer 16.
Bit[23] is for the logo layer. The logo layer is the top-most layer and is blended on top of all other layers.