OV7670 interface cannot get product ID

[theparitt]

Posted on July 11, 2012 at 00:52

Hi, 

        I have a problem with interfacing OV7670 camera. I connect only 4 wires from Ov7670 to my stm32f4board, SIO_C, SIO_D, 3V+ and GND. Then I tried to read product id of the camera. It always send 0xFF. I am not sure that I need to connect OV7670 XCLK pin since I just test for SCCB communication. Thanks #stm32f4discovery #pwm-output

[Tesla DeLorean]

Posted on July 11, 2012 at 05:36

The first rule for synchronous logic is to supply a clock, the second is to make sure you reset it properly.

As XCLK has a min spec of 10 MHz, I seriously doubt DC is going to cut it.

[theparitt]

Posted on July 11, 2012 at 16:05

Thanks Neo for your reply. I think I need to buy a crystal for my OV7670 camera.

:)

[theparitt]

Posted on July 12, 2012 at 00:10

Oh yeah. thanks. Now i use Timer to create clock signal. Everything is work!!!!

:)

[hendalage]

Posted on September 16, 2013 at 05:13

hi,

can someone please give me a basic code to grab an image from the OV7670 camera using STM32F3 disco board? I have the OV7670 camera that comes without the FIFO buffer. thanks in advance :)

[michaelmccartyeng]

Posted on September 17, 2013 at 17:16

With the F3 normally 20x160there is not enough memory to even store one image. If you search google for ''color following bot ov7670'' there was a bot that used the F3 to follow color on the fly, it never ''stored'' the image anywhere though.

The smallest image you can get from that (non jpg) camera is 120x160x2 which is around 38K. Unless you have that much memory you cant buffer the image long enough to send it anywhere. Advice, use the F4

[armindavatgaran]

Posted on April 22, 2015 at 16:44

Hello

I can write to registers but can't read them, what is the reason?I supply xclk pin with 42MHz sysclk coming from MCO2.Thanks.