crazyclock

Crazyclock is a clock that can go faster or slower than normal clock.

In other words: crazy minute can last more than, or less than 60 real seconds. Crazy time can be scaled to run for example twice as fast:

1. By default Crazyclock starts in normal mode
   • it shows real time
2. Let's assume that at 12:00 someone goes crazy
   • time should run twice as fast as normal time
3. As a result after one minute the Crazyclock will show 12:02

For more details see How it Works section.

Table of Content

• Hardware
  • Schema
• How it Works
  • Simple Example
  • When the Scaling Factor Changes
• Development
  • VS Code
  • Console
  • Working with Arduino IDE
  • working with Arduino CLI
• Fritzing Parts
• Automated Tests
  • Requirements

Hardware

You are going to need:

• ESP8266 (wemos or nodemcu version)
• 1602 LCD screen with i2c converter
• rotary encoder, i.e. KY-040
• real time clock, i.e. DS3231

Schema

How it Works

In short Crazyclock uses real time and a scaling factor to calculate crazy time:

• it checks how much of real time passed
• and calculates the crazy time using the scaling factor

It calculates the crazy time in the main program loop without using delay(ms) function.

Simple Example

1. When the program starts it shows normal time
   • scaling factor being 1
2. At some time t₀ someone changes the scaling factor to 2
3. Now we should show time flying twice as fast. We do it by:
   • calculating how much of real time passed
   • multiplying tha by 2
   • adding that to t₀

When the Scaling Factor Changes

1. Get t₀ as the real time when scaling factor was configured
2. And c₀ as the crazy time for that moment
3. Let T be how much time passed since t₀:
   • T = t_now - t₀
4. And then it knows how much crazy time passed from t₀:
   • C = T * scaling factor
5. For current crazy time we get crazy starting point c₀ and increase it by passed crazy time C:
   • c_now = c₀ + C

Development

VS Code

You might want to install C++ Tools plugin.

Install Clang-Format extension and choose it for formatting (xaver.clang-format).

To format currently edited file use [ctlr] + [shift] + [i] keyboard shortcut.

Console

To format all files at once (with clang-format installed on your system):

clang-format -style=llvm -i crazyclock.ino
find src -iname "*.h" -o -iname "*.cpp" -o -iname "*.ino" | xargs clang-format -style=llvm -i

Working with Arduino IDE

We keep components in src folder.

Working with arduino-cli

Arduino CLI setup

1. Install arduino-cli

2. Create configuration file: arduino-cli config init

3. Add esp8266 URL for board manager:

   arduino-cli config add board_manager.additional_urls https://arduino.esp8266.com/stable/package_esp8266com_index.json
   

4. Configure the autocompletion for command-line (optional step)

5. Install Wemos D1 Mini board:

   arduino-cli core update-index
   arduino-cli core install esp8266:esp8266
   arduino-cli core list
   arduino-cli board listall esp8266:d1

Connecting esp-8266 (or Wemos)

1. Watch for logs with: sudo dmesg -w | grep USB
2. Connect your device via USB
3. Write down the ID for the USB device (i.e. ttyUSB0)
4. Show permissions for the device: ls -lah /dev/ttyUSB0
5. Write down the group of the device (i.e. uucp)
6. Add your user to the above group: sudo usermod -a -G uucp $USER
7. logout and login again to apply changes

Compile and Upload

In root directory:

1. Install required libraries (i.e. hd44780):

   arduino-cli lib install "hd44780" "NTPClient" "RotaryEncoder" "Time" "Timezone" "DS3231" "Debouncer"

2. Compile: arduino-cli --verbose compile --fqbn esp8266:esp8266:d1

3. Upload: arduino-cli --verbose upload --fqbn esp8266:esp8266:d1 --port /dev/ttyUSB0

Fritzing Parts

1. KY-040 Rotary Encoder
2. Wemos D1 Mini

Automated tests

Requirements

1. AUnit library: arduino-cli lib install AUnit
2. EpoxyDuino v1.6.0 in crazyclock libraries/EpoxyDuino folder
3. Set environment variable ARDUINO_CLI_DIR for arduino-cli libraries:

   export ARDUINO_CLI_DIR=${HOME}/Arduino

4. Execute tests:

   make -C src/ make_all && make -C src/ runtests