Now onto features that may or may not be implemented:

• Serial communication to set the time in a batch configuration
• GPS time
  • Or radio controlled time
  • Or NTP (time.google.com or otherwise)
• LED panel (video wall panel, monochrome) support
  • Or I2C LCD display
  • Or SPI LCD display (128x64 GLCD/OLED)
  • Or simple LED matrix display
• Adjustable volume
  • Automatic volume?
  • Digital configurable volume perhaps?
• Adjustable brightness
  • Especially automatic dimming
• Multiple languages
  • If voice segments exceed 255 it won't work
  • oh
  • No worries, you add more folders per language
• ESP32 for NTP support
  • Or ESP8266?
  • Or MEGA2560???
  • WIRED NETWORKS?????
• Proximity sensor for voice activation
  • Wave your hand in front of the clock to make it say the time
• Integrity check
  • Not everything, just basic things like SD card read failure, invalid time, low battery and speaker check
  • SD card read failure and speaker check could be done by just reading the report from the module and attempting to play 000.mp3 which is a start-up sound
  • Maybe have a secondary beeper inside to show that the initialization failed for voice prompt
  • Have voice prompt for recoverable failures like invalid time
• Seasonal greetings
• Voice mapping documentation for custom voices
  • Must include support for BUSY pin
  • The voice must not rely on the static time, but on the status change from PLAYING to IDLE
• IR remote
• Temperature readout in both Celsius and Fahrenheit
• Time-dependent greeting ("Good morning", "Good afternoon", and "Good evening")
• Randomized starting line ("The time is", "It's", "It is")
• Date and year readout ("Today is Saturday, January fifth, 2019.")
• Verbose time ("It's a quarter to nine")