User`s guide
4: Setup and Conguration • 20
©2014 Axia Audio - Rev.1.3.8
GPIO Routing
Axia devices support a function known as GPIO
routing. When a port is congured for this, the GPOs
(outputs) of the congured port will mimic the behavior
of the GPIs (inputs) from the designated port.
Just as we think of audio routing, the output of a de-
vice is the input of another device.
GPI pin of Port B goes low -> GPO pin of Port A
goes low
To accomplish this, a port should be congured with
the IP address and port value of a designated device. Ex-
amples of this are:
192.168.2.32/3 port 3 on device at IP value 192.168.2.32
192.168.2.50:4013/4 port 4 on device at IP 192.168.2.50
on TCP port 4013
127.0.0.1/2 same device (loop back address) on port 2
In order to assign a physical port the functions of the
station’s Main GPIO port, use port routing.
Figure 4-9
As shown in gure 4-9, the hardware port and the
main port are mapped to each other, or referred to as
GPIO routing. The inputs on the hardware port will be
reected as GPOs in the main port based on the line
“127.0.0.1/1”. So the active input on pin 2 results in GPO
pin2 being active which triggers the Busy function. In
the reverse, when port 1, the hardware port, is cong-
ured with “127.0.0.1/2”, the GPI activity of the main port
will equate to a GPO (output) on the physical port. En-
gaging the Mic Mute function will trigger a GPI on pin 4
of the main and a GPO pin 4 on hardware port.
In the case of desktop intercom stations, there is no
hardware GPIO port. Using the GPIO port of equipment
that is secured in an equipment rack and GPIO routing
allows to bring the logic from the station to other equip-
ment without needing to wire direct to the desktop sta-
tion.
For a situation where an Axia console based inter-
com station has an external source congured to inter-
face with a PTT (Push-to-talk) radio, the Axia GPIO
xNode near the radio would have a port congured as
192.168.2.50:4013/2. Where the DSP engine associated
with the surface is IP address 192.168.2.50. Port 4013
is the port where GPIO trafc is supported on DSP En-
gines (this is different than other devices that use port
93). The Aux 1 GPIO port used for the External source is
known as value 2 (since value 1 is the main port).
Mute of Station speakers
A common need is the muting of the speaker asso-
ciated with the station. This applies to rackmount and
desktop models. Axia console intercom stations use the
External Preview function, the preview mix is already
muted when a local mic is active.
The Main GPIO port has dened two commands
which will mute the speaker.
GPO Pin 1 – Mute Speaker
GPO Pin 2 – Busy (also mutes speaker)
Using a hardware GPIO port which has been cong-
ured with GPIO routing (previous section) and wiring a
relay to GPI pin2 of the port will trigger the Busy func-
tion when the relay is active.
Figure 4-10