Revision A—12 September 2017
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Q-SYS™ Accessory
Technical Notes
I/O-8 FLEX
Type
Conceptual schematic
Control pins
Notes
Input
Potentiometer (2-wire)
—
In this setting,
the external potentiometer is connected merely as a
rheostat—a variable resistor. The internal pullup resistor
is enabled, so the variable resistor delivers a variable
voltage to the GPIO input; the GPIO circuitry interprets the
voltage as a proportion between minimum and maximum.
This configuration also requires calibration of the pot’s
minimum and maximum positions.
• Calibrate Maximum
• Calibrate Minimum
• Maximum Position
• Minimum Position
Calibrate the minimum and
maximum positions of the
pot.
Analog Input (0–24 V, low Z)
—
In this setting
the GPIO reads the positive analog voltage presented to its
input terminal.
Raw
—
Combines features of both analog and digital
inputs.
Pullup enable
See the tech note pertaining
to the
Raw
input.
Output
Digital Output (TTL 3.3 V)
—
The output feeds
a 3.3 V TTL digital input or its equivalent. The two states
are logic high (1) and logic low (0).
Open Collector (100 mA)
—
In this setting
each output can sink up to 100 mA of current, making it
suitable to actuate the low side of a relay (shown), LED, or
other device. A relay, for example, can be used to switch
higher levels of voltage or current.
CAUTION: The GPIO output is not fused. Current greater
than 100 mA can damage it.
For 12 V relays or other
loads, use the +12 V source
provided. For higher-voltage
relays or loads, use an
external DC supply (up to
24 V).
Raw
—
Similar to the Digital Output setting, except it
offers an “invert” option.
Invert
See the tech note pertaining
to the
Raw
output.
Application Examples
Shure MC396 Microphone Button/Light
Clockaudio CH32 Touch Sensitive Switch
Purpose: To convey switch actuations to the Core and turn the mic’s status light either
red or green (the LED cannot be turned off), as directed by the Core’s GPIO output.
The mic receives phantom power from the I/O-8 Flex. The I/O-8 Flex can accommodate
as many as eight MC396 mics.
Set the GPIO input and output both to
Digital
.
Mic DIP switch settings:
1 Down
2 Either (does not matter)
3 Up
red
black
bare
GPIO Input
GPIO Output
Ground
to mic
I/O-8 FLEX
Purpose: To convey switch actuations to the Core and turn the LED ring of the
Clockaudio CH32 touch sensitive switch either red or green.
As many as three CH32 switches can share the same +12 V and GND pins. A I/O-8 Flex
can power no more than three CH32 switches; a suitable external 12 V power supply,
though, may allow four switches.
Set GPIO input to
Contact Closure
. Set both GPIO outputs to
Digital
.
pin 2
pin 3
pin 4
GPIO Output (Red LED)
Ground
+12 V
to mic
RJ45
I/O-8 FLEX
GPIO Input (Button)
GPIO Output (Green LED)
pin 5
pin 6
