General Purpose Input Output (GPIO) has been a common function in radio studios for many years. Though AoIP has changed the way in which components interface with one another, logic states between gear remains widely depending on this legacy method of wiring.
From the beginning, Axia has endeavored to make the process of configuring GPIO as plug-and-play as possible, and the strategy used to achieve this has been to define behavior through the use of profiles. Each Source Profile (as outlined in Chapter 3) defines how the 5 GPI, 5 GPO, and 15 pin GPIO ports behave based upon how each is expected to be employed in a typical studio. Information about each Source Profile plus tables for GPIO ID and pin-outs are provided below.
Source profiles include:
Line Input – Used for any general audio source.
Computer Player – Similar to Line Input, but with a different logic control commonly found with PC-based automation systems. For example, pressing the “On” button while the source is already in the “on” state triggers the next event in the automation.
Phone – Defines the source as a hybrid or broadcast phone system input. Single line phone hybrids commonly want the line to be seized when a state is changed on the console, such as when the channel is turned on or set to a preview state. A summed mono mix-minus is automatically created for the source, and controls for Telos products will be available.
Codec – Links to remote codecs often require a GPIO to trigger IFB communication and a dual mono mix-minus for the source consisting of one PA feed (right channel) and one talent feed with talkback (left channel).
Operator Microphone – This is the board op’s mic which often requires different GPIO functions than other studio microphones.
CR Producer Microphone – The in-studio producer’s mic may not have access to the console but often requires the same controls as the operator.
CR Guest Microphone – Used for any other mic in the control room.
Studio Guest Microphone – Similar to the CR Guest Microphone, but with different monitor muting requirements.
External Microphone – Used for any mic located outside of the CR or studio, this functions like a Guest microphone but without any muting logic.
Studio Feed – Typically a source that receives a backfeed and generates an IFB backfeed in return. This is intended for an external studio source for which you wish to create a talkback channel.
Record Mode – Provides GPIO control of the various Record button functions
External Timer Control – Provides GPIO control of the count-up timer.
V-Mixer – Controls the Vmixer “On” states.
Show Profile – Allows GPIO control and status of Show Profiles.
The following tables show pin numbers as they would appear on a Telos Alliance xNode with 15-pin GPIO ports. Common pins that are not profile-specific are as follows and are not listed in the individual tables:
Pin 7 – GPO Common pin, typically tied to GND by application
Pin 8 – GPIO port GND
Pin 9 – 5vDC supply
Pin 10 – GPI common pin, typically tied to 5vDC by application
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
Inputs (GPI)
Outputs (GPO)
ID
Name
Pin
Notes
GPI 1
ON Command
11
Momentary turns ON console channel and triggers START pulse
GPI 2
OFF Command
12
Momentary turns OFF console channel and triggers STOP pulse
GPI 3
PREVIEW Command
13
Active = PREVIEW ON
Not Active = PREVIEW OFF
GPI 4
RESET Command
14
Momentary turns OFF channel w/o generating a GPO STOP pulse
GPI 5
READY Command
15
Latch to indicated READY (OFF button illuminated) for profiles defined with the READY enable
ID
Name
Pin
Notes
GPO 1
ON lamp
1
Latching during ON state
GPO 2
OFF lamp
2
Latching during OFF state and READY command if enabled
GPO 3
PREVIEW lamp
3
Latching during PREVIEW state
GPO 4
START pulse
4
Momentary at transition to ON
GPO 5
STOP pulse
5
Momentary at transition to OFF
ID
Name
Pin
Notes
GPI 1
ON Command
11
Momentary turns ON console channel and triggers START pulse
GPI 2
OFF Command
12
Momentary turns OFF console channel and triggers STOP pulse
GPI 3
PREVIEW Command
13
Active = PREVIEW ON
Not Active = PREVIEW OFF
GPI 4
Not used
14
GPI 5
READY Command
15
Latch to indicated READY (OFF button illuminated) for profiles defined with the READY enable
ID
Name
Pin
Notes
GPO 1
NEXT pulse
1
Momentary when ON button pressed and already in the ON state
GPO 2
OFF lamp
2
Latching during OFF state and READY command if enabled
GPO 3
PREVIEW lamp
3
Latching during PREVIEW state
GPO 4
START pulse
4
Momentary at transition to ON
GPO 5
STOP pulse
5
Momentary at transition to OFF
ID
Name
Pin
Notes
GPI 1
ON Command
11
Momentary turns ON console channel and triggers START pulse if ON is configured to answer hybrid
GPI 2
OFF Command
12
Momentary turns OFF console channel and triggers STOP pulse if ON is configured to answer hybrid
GPI 3
PREVIEW Command
13
Active = PREVIEW ON
Not Active = PREVIEW OFF
GPI 4
Not used
14
GPI 5
READY Command
15
Latch to indicated READY (OFF button illuminated) for profiles defined with the READY enable. Can be used to provide ring indication.
ID
Name
Pin
Notes
GPO 1
ON lamp
1
Latching during ON state
GPO 2
OFF lamp
2
Latching during OFF state and READY command if enabled
GPO 3
PREVIEW lamp
3
Latching during PREVIEW state
GPO 4
START pulse
4
Momentary to seize line based on hybrid control configuration
GPO 5
STOP pulse
5
Momentary to release line based on hybrid control configuration
ID
Name
Pin
Notes
GPI 1
ON Command
11
Momentary turns ON console channel
GPI 2
OFF Command
12
Momentary turns OFF console channel
GPI 3
PREVIEW Command
13
Active = Routes channel audio to Preview and mutes channel
GPI 4
Not used
14
Mutes console channel
GPI 5
READY Command
15
Active = Initiates Talkback to Source from Operator Mic or Ext Talk
ID
Name
Pin
Notes
GPO 1
ON lamp
1
Latching during ON state
GPO 2
OFF lamp
2
Latching during OFF state and READY command if enabled
GPO 3
TALK TO CR lamp
3
Latching during active TALK TO CR state
GPO 4
MUTE lamp
4
Latching during active MUTE state
GPO 5
TALKBACK lamp
5
Latching during an active TALKBACK
ID
Name
Pin
Notes
GPI 1
ON Command
11
Momentary turns ON console channel
GPI 2
OFF Command
12
Momentary turns OFF console
GPI 3
TALK TO STUDIO Command
13
Active = TALK TO STUDIO and will MUTE channel
GPI 4
MUTE command
14
Mutes channel console
GPI 5
TALK to source in Preview Command
15
Active = Initiates Talkback to channels that are in PREVIEW from Operator Mic and will MUTE channel
ID
Name
Pin
Notes
GPO 1
ON lamp
1
Latching during ON state unless TALK or MUTE are active
GPO 2
OFF lamp
2
Latching during OFF state
GPO 3
TALK TO STUDIO lamp
3
Latching during active TALK TO STUDIO state
GPO 4
MUTE lamp
4
Latching during active MUTE state
GPO 5
TALK to source in Preview lamp
5
Latching during an active TALK
ID
Name
Pin
Notes
GPI 1
ON Command
11
Momentary turns ON console channel
GPI 2
OFF Command
12
Momentary turns OFF console
GPI 3
TALK TO STUDIO Command
13
Active = TALK TO STUDIO and will MUTE channel
GPI 4
MUTE command
14
Mutes channel console
GPI 5
TALK to source in Preview Command
15
Active = Initiates Talkback to channels that are in PREVIEW from Producer Mic and will MUTE channel
ID
Name
Pin
Notes
GPO 1
ON lamp
1
Latching during ON state unless TALK or MUTE are active
GPO 2
OFF lamp
2
Latching during OFF state
GPO 3
TALK TO STUDIO lamp
3
Latching during active TALK TO STUDIO state
GPO 4
MUTE lamp
4
Latching during active MUTE state
GPO 5
TALK to source in Preview lamp
5
Latching during an active TALK
ID
Name
Pin
Notes
GPI 1
ON Command
11
Momentary turns ON console channel
GPI 2
OFF Command
12
Momentary turns OFF console
GPI 3
TALK TO CR Command
13
Active = TALK TO CR (Preview channel) and will MUTE channel
GPI 4
MUTE command
14
Mutes channel console
GPI 5
Not used
15
ID
Name
Pin
Notes
GPO 1
ON lamp
1
Latching during ON state unless TALK or MUTE are active
GPO 2
OFF lamp
2
Latching during OFF state
GPO 3
TALK TO CR lamp
3
Latching during active TALK TO CR state
GPO 4
MUTE lamp
4
Latching during active MUTE state
GPO 5
Not used
5
ID
Name
Pin
Notes
GPI 1
ON Command
11
Momentary turns ON console channel
GPI 2
OFF Command
12
Momentary turns OFF console
GPI 3
TALK TO CR Command
13
Active = TALK TO CR (Preview channel) and will MUTE channel
GPI 4
MUTE command
14
Mutes channel console
GPI 5
Not used
15
ID
Name
Pin
Notes
GPO 1
ON lamp
1
Latching during ON state unless TALK or MUTE are active
GPO 2
OFF lamp
2
Latching during OFF state
GPO 3
TALK TO CR lamp
3
Latching during active TALK TO CR state
GPO 4
MUTE lamp
4
Latching during active MUTE state
GPO 5
Not used
5
ID
Name
Pin
Notes
GPI 1
ON Command
11
Momentary turns ON console channel
GPI 2
OFF Command
12
Momentary turns OFF console
GPI 3
TALK TO CR Command
13
Active = TALK TO CR (Preview channel) and will MUTE channel
GPI 4
MUTE command
14
Mutes channel console
GPI 5
Not used
15
ID
Name
Pin
Notes
GPO 1
ON lamp
1
Latching during ON state unless TALK or MUTE are active
GPO 2
OFF lamp
2
Latching during OFF state
GPO 3
TALK TO CR lamp
3
Latching during active TALK TO CR state
GPO 4
MUTE lamp
4
Latching during active MUTE state
GPO 5
Not used
5
ID
Name
Pin
Notes
GPI 1
ON Command
11
Momentary turns ON console channel
GPI 2
OFF Command
12
Momentary turns OFF console
GPI 3
TALK TO CR Command
13
Active = TALK TO CR (Preview channel) and will MUTE channel
GPI 4
MUTE command
14
Mutes channel console
GPI 5
Not used
15
ID
Name
Pin
Notes
GPO 1
ON lamp
1
Latching during ON state unless TALK or MUTE are active
GPO 2
OFF lamp
2
Latching during OFF state
GPO 3
TALK TO CR lamp
3
Latching during active TALK TO CR state
GPO 4
MUTE lamp
4
Latching during active MUTE state
GPO 5
Not used
5
ID
Name
Pin
Notes
GPI 1
MUTE CR Command
11
Mutes Preview and Monitors when active
GPI 2
DIM Command
12
Dims Monitors when active
GPI 3
EXT Preview Command
13
Routes External Preview defined in Show Profile to Preview
GPI 4
TALK TO EXT Command
14
Route Operator Mic or Ext Talk source as defined in Show Profile to Talk to External output
GPI 5
Not used
15
ID
Name
Pin
Notes
GPO 1
MUTE lamp, ON AIR lamp
1
Latching during Studio MUTE state
GPO 2
DIM lamp
2
Latching during DIM state
GPO 3
START/RESET lamp
3
Momentary indication of Timer change state
GPO 4
Not used
4
GPO 5
TALK TO STUDIO lamp
5
Latching during an active TALK TO STUDIO
ID
Name
Pin
Notes
GPI 1
Not used
11
GPI 2
Not used
12
GPI 3
Not used
13
GPI 4
Not used
14
GPI 5
Not used
15
ID
Name
Pin
Notes
GPO 1
RECORD ACTIVE lamp
1
Latching while in Record mode
GPO 2
RECORD NOT ACTIVE
2
Latching while Record mode is off
GPO 3
Not used
3
GPO 4
RECORD pulse
4
Momentary when entering Record mode
GPO 5
STOP pulse
5
Momentary when exiting Record mode
ID
Name
Pin
Notes
GPI 1
START command
11
Momentary starts timer
GPI 2
STOP command
12
Momentary stops timer
GPI 3
RESET command
13
Momentary resets timer
GPI 4
FREEZE command
14
Latching freezes timer view
GPI 5
Not used
15
ID
Name
Pin
Notes
GPO 1
START lamp
1
Momentary at timer start
GPO 2
STOP lamp
2
Momentary at timer stop
GPO 3
RESET lamp
3
Momentary at timer reset
GPO 4
FREEZE lamp
4
Active during freeze state
GPO 5
Not used
5
ID
Name
Pin
Notes
GPI 1
In 1 ON command
11
Normal: Latch to turn ON
Toggle: Momentary for ON/OFF
Radio: Last momentary is ON, all others OFF
GPI 2
In 2 ON command
12
GPI 3
In 3 ON command
13
GPI 4
In 4 ON command
14
GPI 5
In 5 ON command
15
ID
Name
Pin
Notes
GPO 1
In 1 ON lamp
1
Active when ON
GPO 2
In 2 ON lamp
2
Active when ON
GPO 3
In 3 ON lamp
3
Active when ON
GPO 4
In 4 ON lamp
4
Active when ON
GPO 5
In 5 ON lamp
5
Active when ON
ID
Name
Pin
Notes
GPI 1
None command
11
Changes to blank profile
GPI 2
Profile A command
12
Changes to A profile
GPI 3
Profile B command
13
Changes to B profile
GPI 4
Profile C command
14
Changes to C profile
GPI 5
Profile D command
15
Changes to D profile
ID
Name
Pin
Notes
GPO 1
Profile None lamp
1
Active when NONE
GPO 2
Profile A lamp
2
Active when Profile A
GPO 3
Profile B lamp
3
Active when Profile B
GPO 4
Profile C lamp
4
Active when Profile C
GPO 5
Profile D lamp
5
Active when Profile D