Tallies Overview

This page gives a short overview of how the tallies work in relation to the camera’s. A simple overview of the tallies in correlation between the server and the streamer is shown below:

_images/overview.svg

Hardware

The hardware for the tallies is an esp8266 microcontroller, as they can be found on Amazon. These microcontrollers are very cheap but are capable of using the 802.11 b/g/n wifi standard(IEEE).

A quick overview of the hardware:

Type

Value

CPU

32Bit RISC based on Xtensa lx106

Instruction RAM

32 KiB

Instruction Cache

32 KiB

User Data RAM

80 KiB

System Data RAM

16 KiB

Flash Memory (External)

4 MiB

Of the 17 GPIO pins available, only 3 are used for the RGB colouring. Wifi is used for communication between the tallies and a server that will tell the tally to turn on the lights.

Software

On the Host a NodeJS server is run that opens a websocket on port 7411. This websockets waits for tallies to connect and sends data to them when connected. The server also connects to the streamer, in our case a Black Magic ATEM that controls the camera’s. The streamer gives information about which camera is active which is passed to the tallies.