The Logitech Z906 is a 5.1 THX-certified surround sound system. It is a powerful system with the ability to decode Dolby Digital and DTS-encoded soundtracks, but it lacks WiFi/network control.

Therefore, this project is a hardware and software solution that allows the unit to be controlled over the internet, adding smart WiFi control capabilities.

The Logitech Z906 usually cannot operate without the console connected, however, this solution removes the need for the console, replacing it with an ESP8266 control board.

The serial control logic for this project is based on the works of zarpli.

To enable the control of the unit over the internet, an ESP8266 microcontroller was used which is a low-cost WiFi connected microcontroller.

The controller can be wired up to the console port or the Z906 using a rewirable DE-15 male plug, in order to make use of TTL serial communication at 3.3V.

Below is a circuit diagram that illustrates how to wire up an ESP8266 NodeMCU microcontroller to the console port.

Here is the pinout of a DE-15 male port (as viewed from the front).

The following pins from the Male DE-15 port should be wired to the ESP8266 in the following configuration:

The connection between the Male DE-15 port and the ESP8266 should look something like this.

If using a rewirable plug, it should look something like this (with a few more cables!)

An environment variables file is included in the project.

An example of this file is provided in the repository (called example-environment.h). This file should be renamed to environment.h and populated in the project.

It contains specific configuration details for your project, including WiFi passwords.

To specify the network credentials you wish to use, the network credentials list can be modified in the environment.h file as follows:

const Wifi wifi_credentials[] = {
  { "YOUR_SSID_1", "YOUR_PASSWORD_1" },
  { "YOUR_SSID_2", "YOUR_PASSWORD_2" },
};

The project makes the following HTTP endpoints available to control all the functions of the Logitech Z906 over the API.

When making a web request to any of these endpoints, the microcontroller will run the desired action, interfacing with the Logitech Z906.

*Please note, use the EEPROM_SAVE function with caution. Each EEPROM has a limited number of write cycles (~100,000) per address. If you write excessively to the EEPROM, you will reduce the lifespan.

The API can be called through any browser. For example:

GET /temperature should respond like this:

Useful requests also include:

• GET /volume/main/set?value=255 Sets the main volume to 100%.

1. Check your wiring and connections are correct.
2. Check your internet connectivity and WiFI credentials.
3. Check you have called /power/on and /input/enable and /mute/off and you're using the correct input.