The GTFPI (Gigabit-Transceiver Front Panel Interface) card is a rail-mounted card that creates TTL-level electrical signals from digital signals exchanged with a NovaCor chassis or PB5 processor card. These signals are made available on interface panels, typically located on the front of a simulator cubicle. All cubicles include at least one GTFPI card, which can connect to one Low Voltage Digital Input/Output Interface Panel and one 250 Vdc Digital Output Interface Panel.