Hi, we have a few examples here for connecting OpenMV to Arduino:
Yes, again please see the examples, you can modify any example to do exactly what you want. For example, see the arduino_uart.py, you can modify that to save snapshot when it receives a message and then save it as main.py to run when the camera restarts. Also please search the forums, this question has been answered so many times before.
Sending an image from the camera to an Arduino is very difficult because the Arduino doesn’t have enough ram to buffer a jpeg. So, you have to write a serial protocol that sends only a few bytes at a time.
Given this type of usage defeats the purpose of our product I would advise against wanting to do this. You should make the OpenMV Cam the master device and the Arduino and I/O interface device only.