Axia DESQ, Инструкция по установке и эксплуатации

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5: C
on
fig
uri
ng G
PI
O •
4
3
©2012 Axia Audio
Referring to the Hybrid Logic Chart, we can see that
when the channel is
Off
, the indicator representing
Output Pin 2 – the
Off Lamp
logic command – is
high. Turning the channel
On
, we see Pin 4 pulse
briefly before Pin 1 goes high: the GPIO has just sent
a
Start
pulse, then lit the
On
Lamp. If you turn the
channel
Off
again, you’ll observe a
Stop
pulse, and
the
Off Lamp
command once again becomes active.
See how easy that was? Simply assigning an existing
audio source to a GPIO port automagically configures
the port for the type of device supplying the audio, and
send the appropriate logic commands to that port when
the source is assigned to a channel.
Connections to GPIO Ports
Input Connections
Current on these inputs must be limited to 20 mA or
less, through the use of a current-limiting resistor. An
external power source (24 volts DC maximum) is rec-
ommended for all inputs and outputs, to prevent ground
loops between equipment. However, if customer equip-
ment is completely isolated, using power from the GPIO
port connectors is acceptable. Figure 5-4 shows details
for both types of connections:
Figure 5-4 GPIO input connections