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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.

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    \$\begingroup\$ "connecting a 555 timer to a circuit with a [...] display which is already connected" - connected to what? Do you have any schematics for this 'already connected' block, or any information we could actually use? \$\endgroup\$ – CharlieHanson Mar 21 '16 at 22:24
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    \$\begingroup\$ If that's a 16*2 character alphanumeric display, you pretty much need a microcontroller in there. At which point, throw away the 555 and use the MCU's crystal oscillator for much more precise timing. If you must avoid an MCU you could do ti with a large board of TTL, but that gets ugly pretty fast. \$\endgroup\$ – Brian Drummond Mar 21 '16 at 23:07
  • \$\begingroup\$ What about an RTC module? \$\endgroup\$ – Monty Mar 21 '16 at 23:24
  • \$\begingroup\$ Check out this youtube.com/watch?v=5kGhoRuhlxM \$\endgroup\$ – Tyler Mar 21 '16 at 23:36
  • \$\begingroup\$ Great video! Exactly what I was looking for. Is there code around for this? Also is it possible to configure this to a timer, stopwatch and possibly alarm? \$\endgroup\$ – Monty Mar 21 '16 at 23:58
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Do not, under any circumstances, attempt to use a 555 as a time-keeping clock. It's convenient and easy to design and adjust, but it is not remotely stable enough. Either make an isolated clock generator from the AC line, or use a crystal oscillator.

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    \$\begingroup\$ Yes. People frequently ignore/fail to grasp how accurate a wall clock really needs to be. An error of 1% works out to over 14 minutes a day. \$\endgroup\$ – Jerry Coffin Mar 22 '16 at 2:09
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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.

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