Sonifex AVN-GPIO GPIO to LAN Transceiver (EMBER+ & UDP)

Vendor: Sonifex
Sonifex AVN-GPIO GPIO to LAN Transceiver (EMBER+ & UDP) The AVN-GPIO is a network interface box from the AVN series that transforms GPIO (General Purpose Inputs & Outputs) into network commands so that...

Sonifex AVN-GPIO GPIO to LAN Transceiver (EMBER+ & UDP)

The AVN-GPIO is a network interface box from the AVN series that transforms GPIO (General Purpose Inputs & Outputs) into network commands so that it can control other hardware or software over a normal network and be controlled by it. It contains a relay and ten GPIOs that may be configured, eight of which can be used for PTP-based programming. It offers virtual GPIO that eliminates the need for additional wiring by enabling the device to be activated by other Sonifex devices on the network or to be triggered by them (virtual GPIO communication occurs via the ethernet connection). The AVN-GPIO can be driven or orders can be accepted from it using Ember+ and UDP commands. Alternatively, units can be interfaced together across a network.

A GPIO device with PTP (Precision Time Protocol) capability is the AVN-GPIO. To achieve a sub-10ns synchronization to the master reference, a hardware clock, such as the AVN-GMCS Grandmaster Clock, is synced with a PTP master using IEEE1588-2008 PTPv2. This indicates that outputs can be triggered at predetermined intervals and that the AVN-GPIO can be used to precisely date input events. In addition to supporting AES67 and Default media profiles, the AVN-GPIO offers a user-configurable Custom profile. It uses PoE (Power over Ethernet) and is encased in a sturdy aluminum box with side slots for screw attachment.

The device's internal web server is used for configuration. This makes it possible to configure PTP and check its status in real time. Physical, timed, and virtual inputs can be routed to physical, timed, and virtual outputs using the GPIO routing webpage that is offered. Through the use of a straightforward UDP messaging system, the AVN-GPIO enables other networked devices to request device status data, such as the moment when an input change happened. It is also possible to write custom programs that use UDP to query this data.

The device has 8 ‘timed’ GPIOs - when used as inputs these can detect the rising and falling edges and will generate a timestamp synced to the hardware PTP clock. This means that the recorded timestamps will be synced within 10ns of the PTP master in a correct setup system. When set up as outputs, a signal can be generated precisely at a time chosen by you and the time at which the output toggles can be configured down to the nanosecond. Alternatively, these timed GPIOs can be configured to act as ‘normal’ GPIOs depending on your application.

There are also two ‘normal’ GPIOs. When normal GPIOs are configured as inputs they can be set to either momentary or latching mode. When set up as outputs, they pull the signal on the GPO pin down to the ground when active.

In addition to having six DC output voltage pins that can be used to power external devices like signs and different sensors and actuators, the AVN-GPIO also features a voltage-free relay contact that can be used to activate external equipment. On these pins, the AVN-GPIO outputs 12V at 500mA total when powered by PoE (Power over Ethernet). The DC input powers the AVN-GPIO, which delivers a total of 12V at 1.5A on these pins. To avoid using more current than the device can supply, the DC outputs are fused, and when the device is powered down, the fuses automatically reset.


  • Motor racing timing: PTP-enabled time outputs can be used to start a race at a specified time, and then PTP-enabled time inputs can be used to accurately record the time when cars pass the finish line with a nanosecond resolution. The results can be queried via UDP messages with a history of previous recordings also stored for querying.
  • To connect legacy equipment, with only hardware I/O, to a network for remote control purposes. Many Redbox units with hardware remotes could now be controlled over a network, for example, the RB-DD4, RB-SD1, or RB-OA3.
  • Button presses can be converted to network commands, for example, to act as inputs to software for event handling, or to control remote equipment.
  • Inputs from mechanical buttons & switches, or devices, can control lights and equipment connected to the AVN-GPIO across a network.
  • Timed control switching, e.g. switching lights on/off at specific times of the day, reconfiguring which light switch turns on/off which light, and/or controlling light on/off via a webpage.
  • Time control of power on/off to test equipment and heating systems, together with providing times at which tests are passed.
  • Controlling the power for other equipment at unattended/remote locations, whilst logging precise event data. (e.g. unattended weather stations).
  • Configuring automated systems, controlling conveyor belts, and turning on/off machinery.
  • A notification system for a control room, to indicate an area that needs inspection which can be connected to an alarm/bell.
  • Signal detection on a Sonifex AVN-CU2/4 commentary unit can be linked to a virtual GPO which is then used as an input to the AVN-GPIO.
  • A physical input to an AVN-GPIO can be routed to a virtual GP output, which could be a virtual input on the AVN-CU2/4. This could be used to change the commentator's on/off air status, turn on/off ducking, or mute/unmute the commentator as examples.
  • A physical input to an AVN-GPIO can be routed to a virtual output, to act as a virtual input on a Sonifex AVN-Portal which can be used to mute/unmute a mix-point.

Key Features

  • 10 assignable GPIOs, 8 of which are PTP enabled.
  • PTPv2 keeps the hardware clock in sync with a PTP master to achieve a sub-10ns accuracy.
  • Single voltage-free relay contact to operate external equipment.
  • Virtual GPIO for sending physical GPIO action commands across a network.
  • A single cable can be used for both power and control.
  • The built-in web server makes the AVN-GPIO easy to configure and allows it to be controlled by any device with a web browser.
  • It can provide power to other devices via DC outputs.
  • Uses Ember+ and UDP for communication, allowing programs to be written to interface with it.
  • A PTP synced hardware clock ensures that when recording input events, even from two AVN-GPIOs a large distance away from each other, the timings are highly accurate (<10ns) to one another.
  • It allows highly accurate activation of outputs - two outputs kilometers away from each other could be triggered with only a few nanoseconds difference when PTP synced.

PTP Timing Specification

Profile Support IEEE 1588 Default Profile, AES67 Media & Customs Profile
Timing Protocol PTPv2, IEEE 1588-2008
Timing Accuracy PTP time stamping resolution 8 nanoseconds


Network 1 x 100 Mbit/s Ethernet (RJ45/100BASE-TX) with Power over Ethernet (PoE)
GPIO, Power Out and Relay 1 x 24-Pin Phoenix Style Terminal Block
DC Power In 1 x 2.5mm locking DC inlet (Max 24V DC)
GPIO, PTP Enabled 8
GPIO Normal 2
Voltage Free Relay Contact 1 NC, NO, Wiper, 12V

Power over Ethernet (PoE)

Standard IEEE 802.3af
Class 0
PD Power Range 0.44 W to 12.94 W
Typical PSE Power Usage TBC 2.3W
Maxl PSE Power Usage 15.4 W

DC Power Out (Using PoE)

Max Voltage 12V DC
Max Currentl: TBC 1.5 A Total

DC Power Out (Using DC Power in)

Max Voltage 12V DC
Max Current  

Ember+ Interface Connection

Interface Type Provider and Consumer
Port 9000

UDP Interface Connection

Port 31780

Equipment Type

AVN-GPIO GPIO to LAN Transceiver (PTP, EMBER+ & UDP)

Physical Specification

Dimensions (Raw) 10.6cm (W) x 7.3cm (D) x 4.3cm (H)
4.2" (W) x 2.9" (D) x 1.7" (H)
Dimensions (Boxed) 17.4cm (W) x 9.5cm (D) x 5.6cm (H)
6.9" (W) x 3.7" (D) x 2.2" (H)
Weight Nett: 0.2kg Gross: 0.3kg
Nett: 0.44lbs Gross' 0.66lbs