Press and hold the [MENU] button untill the controller display shows ‘Camera OSD on/off’:

If a camera is connected to the controller and correctly configured, the OSD of the camera (on the HDMI and SDI outputs) will be displayed on the monitor.

Below is the OSD menu of the CM7x-IP:
 

NOTE: the [MENU] button will be lit red and turns off after a moment. The controller is now ready to navigate the OSD of the camera. The [JOYSTICK] navigates up and down through the menu. To choose an menu item, twist the [JOYSTICK] to TELE (clockwise). To change a value of a menu setting, move the [JOYSTICK] to the left or the right. To move the menu up one level, twist the [JOYSTICK] to WIDE (anticlockwise) or use the [MENU] button.

* Read also How can I open the OSD menu of my camera?