Prior Scientific Inc.'s ProScan II controls up to six stepper motors, a motorized stage, a focus motor, three filter wheels and three shutters. The system can be programmed and controlled via the USB interface or either of two serial ports, or by the company's touch screen keypad for stand-alone operation without software. A fourth axis driver controls sample rotation. Four TTL inputs and outputs trigger camera shutters, relays and line-scan cameras. The system is compatible with most third-party imaging software and integrates easily into existing systems.