How would you go about connecting a 555 timer to a circuit with a 16x2 LCD display, which is already connected, to create a digital clock that counts the time? Do you have a sample of how this code would work? I have researched online and found nothing tangible.
Your best bet is probably to use an Arduino (one with a crystal, not a ceramic resonator). You can find code examples on the net that include the LCD, and you can easily customize them.
If you want to get fancy, use a Raspberry Pi or Beaglebone and implement NTP protocol to synchronize time with a network time server using your Wifi.