GPO – General Purpose Output
Note: In Version 0.2.0 software (current as of May 2010) the GPO functions are
disabled. An upcoming software release will re-enable this function and add
additional functionality to the GPO interface.
AirAura provides four General Purpose Output (GPO) circuits that may be used
in a variety of ways. Like the GPI circuits, the GPO interface utilizes optoisolators
in order to provide high electrical isolation from the outside world.
Unlike the GPI circuits each of the GPO’s has completely isolated return circuits
— that is, unlike the GPI port they do not share a common return. Because of
this each GPO may be used in any way the end user chooses without regard to
cross coupling between unrelated external circuits.
The optoisolators on the GPO interface are rated at a maximum isolation of 350
Volts AC or DC. Because of their “AC” input rating, the polarity of external circuit
polarity is unimportant and therefore the GPO pins are simply defined as
“Source” and “Return”.
The MAXIMUM permissible load current is 100 milliamps (0.10Amperes).
The pin assignments for the rear panel DB-9 GPO connector is as follows:
GPO Number
Source Pin
Return Pin
One 2 6
Two 3 7
Three 4
8
Four 5 9
Note that Pin 1 has no connection.
