Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Altera_Forum
Honored Contributor I
801 Views

VIP Suite Clocked Video Input/Output Sync Problem

Hi 

 

I'm a newbie trying to use the Video and Image Porcessing Suite with the Altera Cyclone III Development Board (EP3C120F780C7) and the Bitec HSMC DVI interface. 

 

 

I tried to get color bars on a screen with this design :  

Test Pattern Generator -> Clocked Video Output : it works. 

 

The parameters for the CVO are : for 1280x720p@60Hz  

1280x720 

 

hor sync. : 128 pixels 

hor front porch : 64 pixels 

hor back porch : 192 pixels 

ver sync : 5 lines 

ver front porch : 3 lines 

ver back porch : 20 lines 

 

My problem is :  

 

I am using the analog interface AD9981 (from Analog Devices) to convert analog video signal to digital video signal. 

My design is :  

Clocked Video Input -> Clocked Video Output 

The AD9981 is configured to work in 720p@60Hz and i keep the same parameters as my first design for the CVO, but I get nothing on screen. 

 

It seems that there is a problem with the horizontal sync output : there are only 14 lines for the vertical back porch although I put 20 lines in the "vertical back porch" parameter 

 

Can anyone help me please!! 

 

Thanks! 

 

Dath
0 Kudos
4 Replies
Altera_Forum
Honored Contributor I
36 Views

Hi Dath 

You should check about In/Out Vid Clock diffrence. 

Are you using same clock?  

If In/Out clock different, It require Frame Buffer in VIP. Good Luck to you!!
Altera_Forum
Honored Contributor I
36 Views

not an easy task.

Altera_Forum
Honored Contributor I
36 Views

Hi dath, 

I am trying create Test Pattern Gen -> CVO. I connected  

vga_clocked_video_vid_clk(clk_25), // vga_clocked_video.vid_clk 

vga_clocked_video_vid_data(rgb_data), // .vid_data 

vga_clocked_video_underflow(), // .underflow 

vga_clocked_video_vid_datavalid(vid_datavalid), // .vid_datavalid 

vga_clocked_video_vid_v_sync(v_sync), // .vid_v_sync 

vga_clocked_video_vid_h_sync(h_sync), // .vid_h_sync 

vga_clocked_video_vid_f(), // .vid_f 

vga_clocked_video_vid_h(), // .vid_h 

vga_clocked_video_vid_v()  

Then assigned it to VGA pins 

assign VGA_SYNC_n = 1'b1; 

assign VGA_R = rgb_data[23:16]; 

assign VGA_G = rgb_data[15:8]; 

assign VGA_B = rgb_data[7:0]; 

assign VGA_BLANK_n = vid_datavalid; 

assign VGA_CLK = !clk_25; 

assign VGA_HS = !h_sync; 

assign VGA_VS = !v_sync; 

 

But it still didnt work. Can you tell me where I should reconnect? 

I would appreciate your help!!
Altera_Forum
Honored Contributor I
36 Views

Frame Buffer is a must in this situation.