Problem : Interfacing OV7670 with Nexys2

[jasonkh12]

I am new to FPGA. I have several problems in connecting OV7670 to Nexys2, so i decide to test wether it is broke. I have tried to connect XCLK with 25MHz output from scaling 50MHz Nexys2 clock, then i connect the pixel clock PCLK to oscilloscope. Unfortunately, i cant see any clock signal on PCLK. I connect the 3.3V and the ground pin properly. Any other pins remain unconnected. Did i miss something? 

[jpeyron]

Hi @jasonkh12,

Welcome to the Digilent forums!

Are you using a completed project?

Here is a complete Nexys 2 OV7670 project done by a community member.

When running this project are you able to get the OV7670 working?

best regards,

Jon

 

 

 

 

[jasonkh12]

On 8/13/2019 at 12:03 AM, jpeyron said:

Hi @jasonkh12,

Welcome to the Digilent forums!

Are you using a completed project?

Here is a complete Nexys 2 OV7670 project done by a community member.

When running this project are you able to get the OV7670 working?

best regards,

Jon

 

 

 

 

Thank you Jon @jpeyron,

I have tried it several times. I am sure that i had connected the ov7670 with the same configuration in its constraint file. However, still, I got the black screen on monitor. I have tested the fpga and monitor with some vga programs and they worked. I presume that my ov7670 might be broke. Is there a way to know if it is really broke? or maybe external electronic circuit should be added? 

 

Thank you very much for your reply. 

[jpeyron]

Hi @jasonkh12,

What specific ov7670 camera module do you have? You should be able to use a logic analyzer to view whats going on with the module. If you have an arduino uno i would suggest trying either this or this to get it working on that platform to ensure the nexys 2 project is not the issue.

best regards,

Jon

[jasonkh12]

Hi @jpeyron, Yes, my ov7670 was broken. I get a new one and it went good. I tried the code you give me before, and have a pretty good image. There was some noise and the color is wrong. I think there are some registers which were set uncorrectly. Am i right? Also, is there any method to get vga image since Nexys2 BRAM only support 18kb? Thank you very much for your reply.