72 lines
2.2 KiB
Markdown
72 lines
2.2 KiB
Markdown
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# wordclock - a word clock
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mlhx@google.com / michaelh@juju.nz
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wordclock is a clock that shows the current time as words such as
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"five past eight" or "quarter to three". The clock is approximately
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400 mm x 400 mm square and uses RGB LEDs to light up the words. The
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LEDs are driven by a ESP8266 and the time and time zone is
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asutomatically fetched from the Internet.
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## Mechanics
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See
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The hardware is made up of four layers of 4 mm laser cut plywood. The
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default design cuts this from 8 A3 sheets which are then overlapped,
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although it should be easy to modify if your laser cutter has a 400 x
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400 mm work area.
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The layers are:
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- A backing layer
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- The LED layer which has a snake pattern for laying the LEDs in
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- The mask layer, which has a cut out for each LED
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- The word layer
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Normal laser printer paper is sandwiched between the mask and word
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layers as a diffuser.
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The layers are held together using 8x M4 bolts.
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## Electronics
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The electronics consists of a 5 m strip of WS2812B LEDs driven by an
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ESP8266. A 5 V 3 A supply feeds the ESP8266 and a 1N5401 between the
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5 V supply and the LEDs drops the supply enough so the 3.3 V output
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from the ESP8266 can reliably drive the LEDs.
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The LEDs are the 30 LED/m model arranged in a 11 wide by 10 high
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grid. The LEDs snake through the hardware with the first LED being in
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the bottom right.
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## Firmware
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The firmware uses CircuitPython 3.0, periodically reads the local time
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from a custom time server, and fades from one set of words to the next
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when the words change.
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## Services
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A small API returns the local time of the caller by looking up the
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timezone based on the IPv4 address.
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## License
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Copyright 2019 Google LLC
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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https://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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## Disclaimer
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This is not an official Google product.
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