LidarVox is a simple synthizer controlled by waiving your hands in the air. The project has following aims:
- Demonstrate how to work with different perepherials which STM32 has:
- EXTI for buttons
- PWM generation for triggering HC-SR04
- ICU for reading response of HC-SR04
- I2C for communicating with LidarLite v3
- DAC + GPT for waveform generation
- Make a demo that would interest not only bearded embedded enthusiasts, but even a three year old child.
- Have fun.
Connect LidarLite v3 to PB6 (SCL) and PB9(SDA) pins. Put capacitors on power line. Without them interference from LidarLite would make HC-SR04 to behave very odd. Connect HC-SR04's trigger to PD12 and echo to PC6. Connect external decoupled 5v power supply to discovery 5v bus. Discovery has protection diode and 5v from USB drops to 4.5. This is not enough for HC-SR04 and it starts to work unreliably in the presense of LidarLite. If your power supply is not decopuled you can fry laptop connected to discovery! Connect a pedal to PA0. You can use built-in button, but it more convinient to switch samples with a larger one. Connect gnd and PA4 to an amplifier. This project does not use CS43L22, so built-in mini-jack is not utilized.
Checkout the repository and ChibiOS_18.2.0
Connect your discovery board and launch openocd
# For new version of dev board
openocd -f board/stm32f4discovery.cfg -f interface/stlink-v2-1.cfg
# For old version of dev board
openocd -f board/stm32f4discovery.cfg -f interface/stlink-v2.cfg
CHIBIOS="path to ChibiOS root" make
In the launched gdb session type load to flash the firmware.