Get everything the way you want it

Settings are an important part of development on any platform, because they let you tweak your system conditions until they’re just right for you, for your project’s needs, or both. The Bela IDE gives you access to all the system settings you could use on the command line, so you have full control over your development environment and how your project runs.

This article describes everything you can do in the Settings tab to customise the settings for your project as well as the IDE.

Table of contents

  1. Run project on boot
  2. Project Settings
  3. Capelet settings
  4. IDE Settings
  5. Other functions
  6. How the settings work

Run project on boot

At the very top of the Settings tab there is a drop down menu labelled Run on Boot. Using this dropdown you can select a project to run when the Bela system powers on and boots up (this article explains running projects on boot in more detail).

Project Settings

Expanding the Project Settings dropdown gives you access to all the settings available for a Bela project. These are:

Setting Description Default Setting
Block size The number of audio frames in each block of audio processed by render() 16
Analog channels The number of active analog channels 8
Analog sample rate The number of times per second that the analog channels are sampled 22,050 samples per second
Digital channels The number available digital I/O 16 channels
Headphone level (dB) Adjusts the volume of your headphones -6dB
Use analog Toggle the analog I/O on or off On
Use digital Toggle the digital I/O on or off On
DAC level (dB) Level of the digital to analog converter on the audio output 0
ADC level (dB) Level of the analog to digital converter on the audio input 0
PGA Gain (dB; left and right) Gain of the programmable gain amplifier on the audio input 10
Disable LED Disables the blue “running” LED Off

As well as these settings there are two additional fields: Command line arguemnts and Make parameters. Using these fields, you can pass command line arguments directly to the Bela core, as well as the Makefile, which is the set of directives used by Bela’s compiler.

These fields are entirely optional. If you’d like to see the commands you can pass to the Makefile, run the following in the Console in the IDE:

root@bela ~/Bela# make help

The settings you see in the Project Settings apply only to the project that's currently open. They're saved automatically, and are loaded when the project opens.

Capelet settings

If you launch the Bela IDE from a Bela system (not a Bela Mini), you will also have the Capelet Settings section. These are settings for the Multiplexer and Audio Expander.


Since these add-ons are only compatible with Bela, these settings are not offered if you connect to the IDE using Bela Mini.

Multiplexer settings

The Multiplexer expands your 8 analog inputs up to a massive 64. Here you can enable your Multiplexer, and specify the number of input channels it should use. You can choose between 16, 32, or 64.

Audio expander

The Audio Expander converts Bela’s 8 16-bit analog inputs and outputs into extra audio channels.

In this section you can enable the Multiplexer and Audio Expander capelets and configure their properties. For the Multiplexer, you can choose between 16, 32 and 64 channels.

For the Audio Expander, you can select particular audio inputs and outputs to be used with the capelet. Enabling an input channel for the Audio Expander rescales the range of that analog input to be between -1 and 1 instead of the default 0-1. It also applies a DC-blocking digital filter so the signal is centred around 0. Enabling an output channel for the Audio Expander similar rescales the range of that analog output to be between -1 and 1.

IDE Settings

The next dropdown contains settings for the IDE. These settings apply to the IDE, so they won’t change if you open a new project.

Setting Description Default Setting
Autocomplete Causes the Editor to autocomplete your code as you type On
Syntax Checking Enables automatic syntax checking in the Editor as you type On
Verbose build errors Enables long-form errors in the console Off
CPU monitoring Enables CPU monitoring to show in the Toolbar On
Xenomai stats Periodically prints detailed logs of Xenomai (real-time Linux) tasks, for debugging Off
Never delete console logs Tells the IDE to store all console logs (will take up space in storage!) Off
View hidden files View the hidden files in your project in the Project Contents section of the Project Explorer tab Off

Other functions

The Settings tab has two other sections. One is Feedback. We are always interested in your feedback about the IDE, especially if you find bugs or encounter problems. We have two links to feedback forms, one for general feedback and one for bug reporting.

There are also some buttons for other system functions. These are:

Function Description
Shutdown Bela Shuts down the board safely and gracefully
Download all projects Downloads all projects on your Bela system including their assets, in a single ZIP file
Update Bela Update your Bela system by uploading a ZIP file. See our guide to updating for details
About Bela Has some general information about Bela and the team

How the settings work

Each project folder on your board contains a settings.json file. This file describes the project settings as command line flags to that are passed to the Bela core when the program is run.