Implementation of Avalon ST-Video protocol

Hello,

I try to implement a Avalon ST-Video Interface in a component inside a video and image processing chain.

The chain I use (from tPad VIP Camera example) works without my component. The present processing chain is : Clocked Video Input/Color Plane Sequencer/Frame Buffer/Clipper/Scaler/Mixer/Control Synchronizer/Frame Buffer/Color Plane Sequencer/Clocked Video Input. It uses camera's frames and displays them on a screen.

For now, in order to learn how use this interface, my goal is just to have with my component a delay of one cycle between the Clocked Video Input and the Color Plane Sequencer.

Here is my VHDL code :

--- Quote Start ---

asi_in0_ready <= aso_out0_ready;

process(clk)

begin

if clk'event and clk='1' then

if asi_in0_valid='1' and aso_out0_ready='1' then

aso_out0_valid <= asi_in0_valid;

aso_out0_data <= asi_in0_data;

aso_out0_startofpacket <= asi_in0_startofpacket;

aso_out0_endofpacket <= asi_in0_endofpacket;

else

aso_out0_valid <= '0';

end if;

end if;

end process;

--- Quote End ---

The problem is just the first frame is displayed on the screen and after it is freezed. I don't understand what is wrong. Could someone help me?

Thank you in avance,