Operating instructions

GUIDE TO INSTALLATION AND OPERATION
FRS-1801 | 5
AES IN/GPI – AES and GPI inputs
The rear panel AES IN/GPI connector (15-pin D-SUB) provides four discrete AES3 digital audio inputs, plus
four GPI contacts used to recall user-configurable presets.
AES IN pinout GPI pinout (110Ω / 75Ω rears)
110 ohm rear
Pin # 75 ohm rear
GPI function
Pin #
AES IN 1 High
1
AES IN 1 GPI USER1
12
AES IN 1 Low
6 GND
GPI USER2
15
AES IN 2 High
2
AES IN 2 GPI USER3
4
AES IN 2 Low
7 GND
GPI USER4
9
AES IN 3 High
3
AES IN 3 Reserved
14
AES IN 3 Low
8 GND
AES IN 4 High
13
AES IN 4
AES IN 4 Low
10 GND
GND
5, 11 GND
The GPI User Presets are contact closures to ground (GND). To select a preset (User 1 to 4) using the GPI,
simply short the preset pin to any GND pin.
• The card detects the transition to ground
• User presets must be configured and saved through the normal operating mode of the FRS-1801.
GPI loading is a “single load” process triggered by a transition to ground: it needs to be activated only for a
short period (around 10 milliseconds) to be detected by the card. Since it is not activated by a level, it is not
necessary to maintain the level at ground after the activation.
GPIs are not operating modes; when loaded, they change only the current card configuration.
AES OUT/GPI – AES and GPI outputs
The rear panel AES OUT/GPI connector (15-pin D-SUB) provides four discrete AES3 digital audio outputs,
plus four GPI contacts (reserved for future use).
AES OUT pinout Future use
110 ohm rear
Pin # 75 ohm rear
GPI function
Pin #
AES OUT 1 High
1
AES OUT 1 Reserved
12
AES OUT 1 Low
6 GND
Reserved
15
AES OUT 2 High
2
AES OUT 2 Reserved
4
AES OUT 2 Low
7 GND
Reserved
9
AES OUT 3 High
3
AES OUT 3 Reserved
14
AES OUT 3 Low
8 GND
AES OUT 4 High
13
AES OUT 4
AES OUT 4 Low
10 GND
GND
5, 11 GND