I am using ov7670 but tx led and rx led do not appear.

I use ov7670 but tx led and rx led keep using ov7670 but I don't see the camera shooting screen and I use cmd with jdk.
And no tx LED or rx LED. Is there any solution for this? Photos are cmd error and camera shooting screen error.
Picture's here. jdk error and realserialportwin error.

dong.png