ZonCoffee is a full-featured PID controller package for Arduino, customized for use with espresso machines. ZonCoffee is written in Processing/Wiring, and includes some code from Tim Hirzel‘s BBCC project.
- Displays set point and current temperature information on LCD
- Rotary encoder adjusts temperature targets without a computer
- Intuitive serial interface, compatible with the BBBC grapher
- Steam and extraction modes with separate temperature targets
- Simple configuration in “Options.h”
Supported Hardware (Version .2)
- 1 rotary encoder with pushbutton (software debounced)
- 1 SparkFun serial LCD
- 1 piezo buzzer (beeps when preheated)
- 1 zero-crossing solid-state relay
- 1 MAX6675 thermocouple chip (free samples available from Maxim IC)
- Additional Details
Average Hardware Cost
The entire project can be built for around $40 (not including an Arduino) assuming you acquire a free sample of the MAX6675 chip. ZonCoffee (as of .2) requires an ATMega168 or higher. The sketch is around 14kB compiled.
Plans for future versions:
- Support for additional thermocouple chips (have defines in options.h to choose which to compile)
- Support for additional display types. Possibly abstract display output functions.
- “No LCD” mode (use LED for indication).
- Release version tailored to PID for popper coffee roasting