Welcome to GravityMon’s documentation!

Note

This documentation reflects v0.5. Last updated 2022-01-09

GravityMon is a replacement firmare for the iSpindle firmware, it uses the same hardware configuration so you can easily switch between them. It’s used to measure gravity in beer and show the progress of fermentation.

For more information on this topic and function please visit iSpindel Homepage .

I started GravityMon because i like to create software and wanted to do some low level programming. I had done a few projects based on esp8266 and also started to brew beer so this combination was quite natural.

The hardware design comes from the fantastic iSpindle project so that is not covered in this documentation.

My approach to this software is a little different from that the original ispindle firmware. The github repository can be found here; GravityMon on Github

Note

This software is in the early stages even though its more than one year old so if you find issues, please open a ticket on github.

I dont take responsibility for any errors that can cause problems with the use. I have tested v0.4 on 5+ brews over the last 6 months without any issues.

The main differences:

• Operates in two modes gravity monitoring and configuration mode

• Send data to multiple endpoints when pushing data.

• Automatic temperature adjustment of gravity reading

• OTA support from local webserver

• Build in function to create gravity formulas

There are also a experimental features such as:

• Using the temperature sensor in gyro instead of DS18B20 (faster)

• Performance measurements (used to optimise code)

For a complete breakdown see the Functionallity

Credits to

Ideas to some of these functions have been picked up from disucssions in the iSpindle forums. This software uses the following libraries and without these this would have been much more difficult to acheive:

• https://github.com/jrowberg/i2cdevlib.git

  This library contains the basic code to interact with the gyro + many more chips.

• https://github.com/codeplea/tinyexpr

  Proccess the gravity formula and calculate the gravity and various corrections.

• https://github.com/graphitemaster/incbin

  Include binary files into the code, used to service html files.

• https://github.com/khoih-prog/ESP_DoubleResetDetector

  Can detect if the reset button is pressed twice, is used to enter WIFI config mode.

• https://github.com/tzapu/WiFiManager

  Configure wifi settings.

• https://github.com/thijse/Arduino-Log

  Logging library for handling different loglevels and configure what sent over the serial.

• https://github.com/bblanchon/ArduinoJson

  Json parser/creator used in configuration files and API’s

• https://github.com/PaulStoffregen/OneWire

  Communication library used for interacting with temperature sensor.

• https://github.com/milesburton/Arduino-Temperature-Control-Library

  Interaction with the DS18B20 sensor

• https://github.com/Rotario/arduinoCurveFitting

  Create the gravity formula.

• https://graphjs.com/

  Render the graphs in the UI.

• https://getbootstrap.com/

  CSS templates for the web page.

Contents:

• Licence
• Releases
  • v0.5.0
  • v0.4.0
• Functionallity
  • The main differences
  • Other features
  • Experimental features
  • Battery life
  • Performance
• Installation
  • Official esptool
  • Configuring WIFI
• Setting up device
  • Status
  • Device
  • Configuration
• Create formula
• REST API
  • GET: /api/config
  • GET: /api/device
  • GET: /api/status
  • GET: /api/config/formula
  • POST: /api/config/device
  • POST: /api/config/push
  • POST: /api/config/gravity
  • POST: /api/config/gravity
  • POST: /api/config/formula
  • Calling the API’s from Python
• Data Formats
  • iSpindle format
  • Brewfather format
  • Influx DB v2
  • version.json
• Compiling the software
  • Tools
  • Code Formatting
  • Targets
  • Source structure
  • Options
• Contributing
• Backlog of changes
  • Documentation
  • Code

Indices and tables

• Index

• Module Index

• Search Page