Hello everyone,
In the coming days I’ll release the complete project for a nice and cheap uHAT for Raspberry Pi Zero (it will work on other RPi models and Asus Thinkerboard too): BassFly uHat
It’s still work-in-progress, but almost done. Stay tuned!
6 Likes
Super super super curious!
Hi, so what will this new board do? I’m intrigued!
Sure!
This board is designed to be modular, with a bare-minimum configuration and some options to add if needed, with additional modules.
For the bare-minimum configuration, the board will have 2x TFA9879/TFA8200 amplifiers onboard (in this case they are equivalent). Those are nice and cheap 5V digital amplifiers with DSP inside and driver already available in mainline kernel. Together with the amplifiers, there will be 4 tactile switches and one RGB led, connected to GPIOs.
The additional modules that can be added to the board are the following (please google them, they are quite common):
- 0.96" I2C OLED DISPLAY MODULE 128X64 SSD1306
- Up to 2x INMP441 MEMS Omnidirectional Microphone Module I2S
Oled screen can be used to display some information using this library
tactile switches can be used for controlling playback, volume and/or shutdown, together with dedicated plugin
RGB led can be used for SD-card activity of for playback status, together with dedicated plugin
I2S Microphones will not be necessary for Volumio at the moment, but they can be used for other project (Google-assistant, Alexa-assistant, voice-triggered in general). I really hope it will be possible to control Volumio with voice commands in the future, so I made the design ready for that.
I will release complete source code and all the necessary files for producing the assembled board from PCB manufacturers. PCBWAY has a running promotion with 30$ assembly fee and free DHL shipping up to 20 pieces. Modules can be added manually or by the manufacturer, upon request.
I will also release some scripts for using the board with Volumio and Raspbian, hopefully I will find someone willing to help for creating a dedicated dt-overlay and make use of the HW mixer, HW EQ and HW DRC (Dinamic Range Compressor).
2 Likes
Hi Darmur,
I am in for the pcb… When thid will be available
Thanks
I will try to finalize everything during the weekend
I’m happy to share with you the first revision of the project: BassFly uHAT. As already mentioned, 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 digital radio.
BassFly uHAT is powered by the following peripherals:
- 2x TFA9879/TFA8200 amplifier from NXP. They have an embedded DSP for HW volume control, HW 5-band equalizer and HW dynamic range compressor; they can deliver up to 2.5W RMS output power each (with 4Ohm load)
- 4x Tactile button, for playback control (play/pause, prev/next, vol-up/vol-down) or for safe shutdown
- 1x RGB LED, for SD-card activity or for playback status indicator
- 1x 0.96" I2C OLED DISPLAY MODULE 128X64 SSD1306 module (optional), to display an information screen including a music frequency spectrum ( https://github.com/antiprism/mpd_oled )
- 2x INMP441 MEMS Omnidirectional Microphone module (optional), not necessary for Volumio at the moment, but they can be used for other projects (Google-assistant, Alexa-assistant, voice-triggered in general)
Full documentation is available on public Github repository, including BOM and SMD positioning files, for automated assembly. Some scripts for using it together with Volumio or Raspbian and step-by-step instructions will be uploaded in the coming days.
Please feel free to download gerber file and documentation, to order PCBs and to copy/improve it, if you like!
https://www.pcbway.com/project/shareproject/BassFly_uHAT.html
regards
Dario
3 Likes
Hi Darmur,
Maybe I ask a silly question, how I should connect the speakers? I think I do not need an external amplifier
În order to order it from pcbway do I need to order a minimum of 5?
Thanks
This board is a compact/perfect solution for a Boombox to throw in your kitchen/garage, thanks for the designs!
The board contains an digital (I2S) amplifier - so kinda a DAC + AMP in one chip 
@Darmur Are you planning to do a small run of pcbs anytime soon? I would be interested in a group buy for example. Even if it’s just PCBs + template, should be able to reflow it, thanks for not going BGA 
You can connect speakers directly on the two screw terminals, amplifiers are already onboard.
Each TFA9879 can deliver up to 2.5W RMS in a 4Ohm speaker, it will be more than enough for a kitchen radio.
Minimum order for bare PCBs from PCBWay is 5 pieces, but if you order 10 you will pay the same price: USD 5 in total.
For assembled PCBs they have an offer ongoing, USD 30 fee for assembly and DHL worldwide shipping (you need to add price of the bare PCBs and price of the components to be soldered). I think this can make sense for at least 5 pieces, 10 will be even better (USD 3 per piece for assembly).
If more people are interested in having few pieces maybe you can organize a group order, I can help with that.
I just sent a quote request for 10 assembled pieces, I’ll let you know the final price as soon as I get it.
Soldering by hand is tricky but doable, if you have good soldering skills and a hot air gun you will manage.
1 Like
Just updated gerber files, thermal via holes were to small for being produced for USD 5. They are fine now (0.3mm)
Hi,
În order to order it from pcbway if I add to cart your project everything is loaded, also BOM or only the pcb… If I want also the asembly service do I need to specify the BOM files?
The asembly service should be done for all 5 pcbs?
Thanks.
it’s very easy, go to this link and select “Add to cart”.
Leave default options for keeping USD 5 offer for 10 pieces, you can change PCB color (solder mask) without extra charge.
For bare PCBs this will be enough, for assembled PCBs you have to scroll down and select the option “Assembly service”, filling the number of pieces you want to have assembled, then calculate the price and add to cart.
When the project is in your cart, you can load missing files, selecting “Add files”
Part List (BOM) Upload -> please select “BassFly_uHat.bom-varA.xlsx”
Uplad centroid file and other -> please select “BassFly_uHat.pos.csv”
You can find both files in github repository. After uploading the missing two files, please select “Submit order now”. It will take some hours to have the final quote, including assembly and components.
Assembly can be done even for one piece only, but you will pay USD 30 of assembly fee in any case, not very convenient. The more you assemble, the less each piece will cost to you.
Please don’t hesitate to ask if you need further help.
Dario, what you did is just amazing!
I love this and would love to have one, plus I would love to help this project and the people which would like to have it.
We (as Volumio) could purchase some and help with the logistics and shipping.
What do you think?
Who is interested in having one?
1 Like
I am in with 3 pieces depends on its final price I may increase it.
Thanks.
I’d be quite interested to fiddle with this!
- Interested!
0 voters
PS: Can I also test a feature of the new forum? 
great, it would be nice if you can support that with logistics, it will make easy for Volumio users to get few and not a complete batch. Do you already know how to proceed for ordering some? If not, I can help.
In the meanwhile I’m also working for a proper driver integration, for making use of the HW volume control.
Let’s start with the order! Yes let me know how and we will proceed
1 Like
Some small updates
driver integration is still work-in-progress, but I have updated GIT repository with some scripts for using the BassFly-uHAT.
SSH needs to be enabled. Open a SSH session and type following commands:
wget https://raw.githubusercontent.com/Darmur/bassfly-uhat/master/scripts/install_bassfly_volumio.sh
chmod a+x install_bassfly_volumio.sh
sudo ./install_bassfly_volumio.sh
Please select “Generic I2S DAC” under Volumio playback options, then reboot. BassFly will eb up and running, ready to play music 