DaveWH

Trying to get an event recorded in Cheetah neurophysiological software by sending the USB1024LS a TTL pulse (0 -> +5V) from scientific equipment. Nothing is recorded. If I send the USB-1024LS the sync out from a signal generator, the system works. What is different between a TTL pulse from a several pieces of equipment and the sync out from a signal generator. I can view the TTL pulsed on an oscilloscope, so they are being generated and sent to the USB-1024LS.