Knowledge Base

Problem

The USB I/O box stops working during or between experiments. Hardware connected to the I/O box (e.g., fear conditioning equipment) does not respond to EthoVision TTL outputs. The I/O box itself may show no power indicator or fail to communicate.

Details

In at least one reported case, the root cause was a broken or failing power supply for the USB I/O box rather than a software or configuration issue. This can present as intermittent or complete loss of TTL output functionality. Should be distinguished from software-side TTL configuration problems or cable/wiring issues.

Solution

1. First, rule out software and wiring causes: verify TTL output is configured correctly in EthoVision Trial & Hardware Control, and check all cables connecting the I/O box to external devices.
2. Check whether the USB I/O box power LED is illuminated. If the LED is off or dim, the power supply may be faulty.
3. Test the I/O box on a different USB port or with a different USB cable to rule out port-level issues.
4. If the power supply is suspected as the fault, contact Noldus support to arrange a replacement under NoldusCare or as a hardware fault. Provide the I/O box model number and describe the symptoms.
5. Do not attempt to repair the power supply internally — replace the unit through Noldus.