arduino-audiobook-player
Arduino-based audiobook player with a focus on simplicity
arduino-audiobook-player
Arduino-based audiobook player with a focus on simplicity
- When powered on, plays the recently played track
- When SD card inserted, plays the recently played track
- When next button is pressed (or clap sensor is actuated), plays the track after the recently played track
- Whenever a different track is played, that track is saved to EEPROM as the recently played track (with wear leveling to greatly incrase the lifespan of the EEPROM)
Possible future extensions:
- Smart sleep detection with last track repeat: If the listener has fallen asleep, then pressing the button should not play the next track but the recently played track (again)
- Distinguish between short press, long press, and double press
- Possibly IR remote control (but this waters down the concept of simplicity)
- Switch between multiple audiobooks
- Set the MP3 module into energy saving mode and wake it up again
- Set the ATmega into energy saving mode and wake it up again
- 3D printed enclosure waevguide/"Transmission line" https://www.youtube.com/watch?v=uujaBjf3Uwg (Also see https://www.youtube.com/watch?v=jN-E1dfMfO0 and http://www.mh-audio.nl/Calculators/TML.html)
Software
Libraries
- https://github.com/PRosenb/EEPROMWearLevel
- https://github.com/Makuna/DFMiniMp3
- https://github.com/xoseperez/debounceevent
Hardware
Using an Arduino Pro Mini (with voltage regulator) proved to produce too many unwanted noises. Hence using a bare ATmega 168P chip without oscillator.
To upload to the bare chip, I am not using a serial programmer, but upload directly from the Arduino IDE using a USBASP with Ctrl-Shift-U. For this to work, I need to set permissions: sudo chmod 666 /dev/bus/usb/*/*
- DFPlayer Mini MP3 Player module with on-board class D amplifier and SD card reader (3 EUR)
- microSD card (4 EUR)
- ATmega 168P bare chip (without oscillator). Core and chip pinout: https://github.com/MCUdude/MiniCore (2 EUR)
- Ekulit BL 77 Speaker (e.g., Reichelt, <3 EUR)
- 3D printed housing, e.g., variation of "3D printed transmission line" - is it worth the effort? Does the speaker need to be glued in? https://www.instructables.com/id/3D-Printed-Transmission-Line-Speaker/
- Breadboard (2 EUR)
- Wires
- Clap sensor (or other interesting sensor in addition to a play button)
Note: An ATTiny might possibly do as shown by https://github.com/accidentalrebel/abplayer-mini but in my test with an ATTiny45 flash storage was too small to use the EEPROMWearLevel library, and the lack of a hardware serial port complicates debugging.
Design inspiration
- Dieter Rams