Arduino Brew/Shot Timer and Temperature Display for LaMarzocco Linea Mini espresso machine

Board

• Arduino Pro Mini / Nano
• In case you have STM32 BluePill board at hand please check my other project: https://github.com/klajkor/lineamini-brewtimer-bluepill

Extension modules and peripherials used:

• SSD1306 OLED display, I2C - optional, please see source code for feature switch (SSD1306_ENABLED)
• MAX7219 LED matrix display - optional, please see source code for feature switch (MAX7219_ENABLED)
• 5x7 dot matrix displaying 3x5 digits (controlled by MAX7219) - for shot timer only
• Holtek HT16K33 LED matrix display, I2C - optional, please see source code for feature switch (HT16K33_ENABLED)
• reed switch, sensing the operation of 3-way solenoid valve
• INA219 voltage and current sensor, I2C
• Note:
  • ILI9340 TFT display NOT supported, not enough free pins on an Arduino ProMicro for that
  • In case you would like to use this display, please check my other project: https://github.com/klajkor/lineamini-brewtimer-bluepill

Libraries used:

• SSD1306Ascii by Bill Greiman - Copyright (c) 2019, Bill Greiman
• LedControl by wayoda - Copyright (c) 2015, Eberhard Fahle
• Adafruit INA219 by Adafruit - Copyright (c) 2012, Adafruit Industries
• HT16K33 - Copyright (c) 2017, lpaseen, Peter Sjoberg

Arduino Pro Mini / Nano pinout connections

I2C bus

• SCK -> pin A5
• SDA -> pin A4

Reed switch (for ensing the operation of solenoid valve)

• D3
• GND

MAX7219 LED matrix controller

• DataIn -> pin D12
• CLK -> pin D11
• CS -> pin D10

Toolchain

• VSCode
• Platform.IO

Copyright (c) 2021, Robert Klajko

BSD license, all text here must be included in any redistribution