> ## Documentation Index
> Fetch the complete documentation index at: https://docs.solidyne.ar/llms.txt
> Use this file to discover all available pages before exploring further.

# Tally Light and GPIO

> Signaling light and GPIO connections

## On-Air Light (Tally Light)

The **Tally Light** output delivers **12 VDC / 150 mA** when the **Microphone Master Button** is enabled.\
It can connect up to **two Solidyne LA100 indicator modules**.

Additionally, the console includes a **built-in on-air light in the chassis**.

<Danger>
  The **Tally Light** output automatically turns off if the load exceeds **150 mA**.
</Danger>

## GPIO

The 3.5mm jacks labeled \*\*GPIO\*\* are general purpose outputs (**GPO**, *General Purpose Output*) designed to control external devices by enabling specific console channels.

* On **DX816**: outputs are generated for microphone channels **MIC-1, MIC-2, MIC-3** and line inputs **USB-1** and **USB-2**.
* On **DX822**: in addition to the above, GPO outputs include **MIC-4, MIC-5** and **MIC-6**.

<Note>
  These control outputs use an **open collector** circuit, functioning like a switch:

  * Inactive state → high impedance.
  * When enabling a channel → the output connects to ground.
</Note>

**Electrical specifications:**

* Maximum: **+24 V - 0.1 A**.

**Connectors:**

* **3.5mm TRS jack** type, located on the rear panel.
* DX816: "MIC 1&2", "MIC-3" and "LIN USB 6&7".
* DX822: adds "MIC 4&5" and "MIC-6".

***

**GPO MIC 1&2** *(same for MIC 4&5 on DX822)*

| Connector | Signal |
| --------- | ------ |
| Sleeve    | GND    |
| Ring      | MIC-1  |
| Tip       | MIC-2  |

**GPO MIC-3** *(same as MIC-6 on DX822)*

| Connector | Signal        |
| --------- | ------------- |
| Sleeve    | GND           |
| Ring      | MIC-3         |
| Tip       | No connection |

**GPO USB**

| Connector | Signal |
| --------- | ------ |
| Sleeve    | GND    |
| Ring      | USB-1  |
| Tip       | USB-2  |