Quantity   Component name
1 × STM32F104C8T6 "Blue Pill" development board
2 × 40x1 angle pin header 2.54mm pin pitch For mounting the "Blue Pill" board to the SMD pads on the back of the board.
1 × XPT8871 Amplifier Chip, SMD If you don't use a separate XH-M125 board,
1 × 470uF Capacitor, SMD If you don't use a separate XH-M125 board,
1 × 100 Ohm Resistor, SMD If you don't use a separate XH-M125 board,
1 × 0.39uF Capacitor, SMD If you don't use a separate XH-M125 board,
1 × 6x1 pin header 2.54mm pin pitch If you are attaching the XH-M125 board, you'll need this. If not, leave it out.
3 × 2x1 angle pin header 2.54mm pin pitch Optional, if you don't want to solder speaker and battery holders directly to the board.
2 × 2xAA battery holder with pigtails. Can't thru hole mount it. Attaches to pin headers on the back of the board, or to the holes they mount in if you solder direct.
1 × Custom PCB. You can't build the project without it.
1 × Stylus I made it out of a stiff piece of copper wire soldered to a less stiff piece of copper wire. It attaches to the pad on the back of the board.. The flexible cord should probably be close to 20cm. Mine is currentlu 15cm and it is a little strain to hit high nites.
16 × WS2812 LED If you don't just use a commercially available LED ring
16 × 0.1uF Capacitor For each LED in the LED ring, if you are not using an external LED ring. I haven't updated this on the PCBs yet.
1 × 4x1 pin header 2.54mm pin pitch If you are using a external LED ring board, you'll need this to attach it. You might need and angle header if your board has surface mount pads instead of thru hole for attaching the pins.
2 × 1k Resistor
2 × 1uF Capacitor For PWM. There is another in the amplifier section if you don't buy the board.
1 × 10k Resistor
1 × 8 Ohm, 0.5 Watt 40-50mm Speaker
1 × SPST switch 2.54mm pin pitch