Automatic DST Bug Fix

Fixed bug that prevented the automatic setting of daylight saving time.

Improved DCF Reception

Updated DCF77 reception algorithm to mitigate decoded time being sporadically off by 1 second.

Time Zones and UI Improvements

• Multiple time zone support
• Manual and automatic daylight saving time
• Internal timekeeping runs at UTC
• Service menu shows last DCF sync date and time
• Improved button debouncing
• Modified second set behavior: Increment by 1 minute if seconds value upon reset was >= 30
• Varius UI bug fixes
• Updated user manual

Minor UI Fix

Minor UI fix: Blink once when resetting alarm via long button press

Usability Improvement

Improved behavior of DCF sync enable flag

Auto-Calibration Accuracy and More

• Increased auto-calibration accuracy to 1/64 of a microsecond
• Reworked DCF77 reception algorithm
• Enabled incremental adjustment of the clock drift (setting 6.1)
• Improved digit scrolling behaviour during manual adjustment
• Reworked countdown timer operation logic
• Implemented calendar week adjustment
• Disabled automatic menu reordering
• Reviewed volatile variable declaration
• Improved Nixie tube uptime reset handling
• Refactored parts of the code
• Updated the user manual

Refactoring

Moved parts of the source code to separate Git submodules.

Optional Debug Values

• Implemented the option to display debug values
• Bugfix: When in timer or stopwatch mode for more than 5 seconds, pressing the "menu" button should bring pack the clock mode. This did not work while the timer or stopwatch is active.

Improve DCF Reception Stability

• Dcf: enter critical sections when accessing dcfBit as an attempt to debug occasional timer calibration 20ppm error
• Refactor

First-Time Boot Initialization

Properly initialize the brightness lookup table and alarm settings when booting for the first time.