The 10-410A/411A range of Digital I/O Modules are suitable for operating external devices, such as heavy duty relays (power, RF and high voltage types), solenoids, lamps etc., or for interfacing with external logic, e.g. a programmable instrument with a BCD interface. Writing and reading can be done at bit, byte or word level to simplify programming effort. Applications include generating control signals, stimulus and sensing status from digital devices. Two choices of output drive are available: TTL for interacting with external logic and Open Collector Transistor for operating external devices with voltages to 50V DC and currents to 500mA. There is also a version with optical Isolation for high voltage or electrically noisy environments.