AVR Metronome

Metronome with speaker and remote vibration module

Modules

Built with

• ATmega 168A-PU
• Qduino Mini
• MCP4161
• TPA2005D1
• HM-10 BLE

Features

• Sound mode with volume control
• Rotary encoder (with push button) user interface
• BPM and basic signatures control
• Tap tempo (button)
• PWM LCD backlight (dimming after a period of inactivity)
• Storing metronome settings in the internal EEPROM
• Custom character display
• Remote vibration module (BLE)
• Default idle state for remote module, receiving disable signal
• MicroUSB charging
• Adjustable sound pitch

Project structure

+-- 
   +-- README.md
   +-- .gitignore
   +-- doc
      +-- eagle
         +-- main
         +-- remote
   +-- metronome          // ATmega metronome main module directory
      +-- Makefile        // compiler and programmer config
      +-- main.c          // entry point
      +-- setup.h         // device main settings
      +-- util.h          // helper macros
      +-- global.h        // extern declarations
      +-- lcd.h           // LCD 2x16 interfacing in 4-bit mode
      +-- lcd.c
      +-- eeprom.h
      +-- eeprom.c
      +-- metronome.h     // core logic of the metronome, ISR handlers
      +-- metronome.c
      +-- usart.h         // serial communication with HM-10 BLE module
      +-- usart.c
      +-- mcp41xx.h       // MCP4161 Digital potentiometer SPI interfacing
      +-- mcp41xx.c
   +-- remote_module      // Qduino (Arduino) remote vibrating module sketch directory
      +-- README.md
      +-- remote_module.ino

Setup

Prerequisites

• make
• avrdude
• avr-gcc

Makefile

Override parameters in Makefile to suit your hardware configuration. Here, Arduino Uno is used as an in-system programmer.

- MCU = atmega168
+ MCU = <your_unit>

- PROGRAMMER_TYPE = avrisp
- PROGRAMMER_ARGS = -b 19200 -P COM4
+ PROGRAMMER_TYPE = <your_programmer_type>
+ PROGRAMMER_ARGS = -b <baud_rate> -P <device_name>

Deployment

Use make flash to compile and save program in flash memory (using avrdude). Use make size to find out about the size of the program.