The present invention provides a network device interface and method for digitally
connecting a plurality of data channels, such as sensors, actuators, and subsystems,
to a controller using a network bus. The network device interface interprets commands
and data received from the controller and polls the data channels in accordance
with these commands. Specifically, the network device interface receives digital
commands and data from the controller, and based on these commands and data, communicates
with the data channels to either retrieve data in the case of a sensor or send
data to activate an actuator. Data retrieved from the sensor is then converted
by the network device interface into digital signals and transmitted back to the
controller. In one advantageous embodiment, the network device interface uses a
specialized protocol for communicating across the network bus that uses a low-level
instruction set and has low overhead for data communication.