Who I am

Hello PCBWay community, this is Dario. I am an Italian electronics engineer, with huge passion for audio and music.

Project Description

I'm happy to share with you a nice project: BassCrab uHAT. It is an expansion board for Raspberry Pi Zero, but it will work fine with other Rasbperry Pi versions (2, 3A, 3B, 4) and with ASUS ThinkerBoard too. It's been designed following the mechanical specification for uHAT form factor.

Together with Volumio it will turn your Raspberry Pi into a tiny but powerful audio player.

BassCrab uHAT is powered by the following peripherals:

• - 1x Audio Codec SGTL5000 from NXP
• - 1x Headphone stereo 3.5mm jack
• - 1x Line-out stereo 3.5mm jack
• - 2x Rotary Encoder with push-button
• - 1x Blue LED
• - 1x socket for 0.96" OLED display

The onboard Audio CODEC is fully supported in the latest RaspiOS and Volumio images, to enable it please add the following string to the config.txt file: dtoverlay=fe-pi-audio

The Rotary Encoders with push-buttons can be used to control the audio playback (play, pause, volume-up, volume-down, previous song, next song, etc.).

Full documentation is available on public Github repository, including BOM and SMD positioning files, for automated assembly.

Please feel free to download gerber files and documentation, to order PCBs and to copy/improve it, if you like!

Volumio Setup

Download the latest Volumio image from the official website, than flash the image on a SD-card, as usual. Please refer to the Quickstart guide for the initial setup of your Volumio-based system.

In the third tab of the initial setup wizard, please enable I2S DAC and select Fe-Pi Audio from the dropdown list

When your system is up and running, please navigate in the Playback Option setting page, and enable the resampling as shown in the following picture

Enable Rotary Encoders for playback control

Within the Plugins section, under User Interface category, install the Rotary Encoder plugin

After the plugin has been installed, please enable it and apply the following settings

Enable User Led for playback status

Within the Plugins section, under User Interface category, install the LedStatus plugin

After the plugin has been installed, please enable it and apply the following settings

Enable OLED Display for clock, music frequency spectrum and track information

Enable ssh on your system following the official procedure, then login into your Volumio system.

Type the following command and follow the on-screen wizard to set-up your local time zone.

sudo dpkg-reconfigure tzdata

Type the following commands to install the MPD OLED plugin

wget https://github.com/supercrab/volumio-plugins/raw/master/plugins/miscellanea/mpd_oled/mpd_oled.zip

mkdir ./mop

miniunzip mpd_oled.zip -d ./mop

cd ./mop

volumio plugin install

volumio vrestart

cd ..

rm -Rf mop

rm -Rf mpd_oled.zip

Type the following command to edit the configuration file and disable the SPI interface (otherwise it will conflict with the Rotary Encoder plugin). Delete or comment the line "dtparam=spi=on", then press CTRL+X and save the changes.

sudo pico /boot/userconfig.txt

Reboot your system, then enable the MPD OLED plugin and apply the following settings

I hope you will enjoy it!

regards

Dario