INB <bit number>
The Input Bit command returns the state of the input bits referenced by the parameter. A non-zero value represents a high voltage and a 0 represents a low voltage.
This command returns a single bit which is useful for making decisions. However host communication benefits
from packed information. Using a controller resident application program it is an option to consolidate input bit status into a single user word if desired.
A Parameter Out Of Range Escape Code will be generated if the parameter references an input beyond the range of the controller.
This list of commands configure DIO 1 as an output, turns DIO 1 off, reads back the value as a input getting a response of 0, and checks the On case as well:
Set Output Bit