ClockLab’s 56-channel interface is a small (8″ wide) box that connects to the computer via a USB cable. Using a USB hub, up to 8 interface boxes can be connected to a single computer, for 448 input channels.
Each interface box has on its face 8 RJ-45, or ethernet-style, connectors. These connectors have 8 pins. As shown in the diagram below, one pin serves as a ground, and the other as inputs for 7 different channels. Each switch (or other input device, such as an infrared motion detector) is simply connected between the ground and one of the signal pins. When the switch closes, the program detects an event on the corresponding input channel.
Each input channel can be used to count events on a switch or other detector. Or it can be configured to detect the lights in the experimental room or chamber. For light detection, a photodetector can be connected to the input channel and the program is configured to store that channel’s data as the light cycle for a specified set of counting channels.