Timezone clocks
| Projects | |
|---|---|
| Participants | Katje |
| Skills | Electronics, PCB design, Programming, Networking, TCP/IP, NTP. |
| Status | Planning |
| Niche | Electronics |
| Purpose | Fun |
Contents
Intro
I thought it would be a fun idea to have some clocks above the entrance way between the main space, and the aux space.
Feature wish list:
- NTP based time, so as to avoid need to change clocks to keep time or for DST.
- LED based displays (Easy to use/see)
- 24 hour clock.
- KISS design that doesn't solely rely on funky code to work.
Basic design thoughts
74HC4543 driver chip, this allows latching of input so all 4 or 6 digits needs just 4 data pins, and 1 pin per digit for latching.
Design questions?
4 digits or 6?
Having 5 clocks with seconds displayed where sink may not be spot on perfect could really jar. Maybe have a 6 digit version for local time, with 4 digit display for the others?
45mm or 56mm ?
Which micro?
Arduino pro mini is cheap, small and should have enough grunt, but could be an interesting challenge getting TCP/IP, NTP, Timezones, DST, and clock functionality all in 2k of ram.
Techwolf12: ESP8266-12 is very cheap (around 6 euro), is programmable by Arduino and has buildin Wifi.
Wired or wifi?
We'll need wires to power it, so ethernet + PoE may be the simplest solution?
Techwolf12: When using the ESP, you will need 3.3v.
Timezones
Which timezones to use?
- Boston
- London
- Amsterdam
- Moscow
- Sydney
Design
Have created an initial draft idea for a design. Schematic: LEDClock-sch.pdf
It's based on a 74hc137 3 to 8 multiplexer, and a 74hc4511 BCD to 7 segment decoder. Will test proof of concept with 0.56" displays.
Status
2017-03-02
Crazy idea discussed on the mailing list.
