spikenzielabs Solder:Time 495, Быстрый старт

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2.
2.
VERY IMPORTANT: Some of the layers have very thin parts that can crack easily. The best way we have found to peel the protective
layer off of these parts is to hold the part down evenly on a flat surface with one hand and peel with the other hand. Holding the part in
the air while you peel may snap the part you are peeling. (Don’t worry after the watch is assembled and screwed together it is very
strong.)
Stacking the watch:
With the battery in the battery holder start making a stack of parts.
Close up of button details:
Battery:
Slide the battery into the battery holder on the Solder : Time PCB with the CR2032 “+” label text facing up. When the battery goes into the
holder the watch should turn on and display 12:00. If not, remove the battery and check your work. After about five seconds the display will go
out, this is normal.
NOTE: As tempting as it may be, don’t touch the battery holder while soldering - you will burn your finger!
5.
5.
Place the front face of the Solder : Time on the top of the stack.
6.
6.
Using your fingers, screw the layers together with the included screws. Don’t tighten them fully until all four screws are installed (this
will help you align the layers).
7.
7.
Almost done, slide the wrist band in from the bottom edge, under the bottom and up through the other hole in the bottom and out the
top edge.
1.
1.
Start with the plastic watch back oriented with the two larger holes at the top and bottom and place the PCB over it.
2.
2.
Next, place the plastic PCB layer part around the PCB, with the open end facing down.
3.
3.
Place the plastic switch layer on top of the PCB layer plastic. The opening for the switch is on the right side.
4.
4.
Place the switch lever into the space on the right side of the Switch Layer. Make sure that the switch touches the Solder : Time button
and does not bind. Test it, the Solder : Time should turn on when pressed and off after a few seconds when released.
How does it work ?:
Parts Selection:
When we came up with the idea for the Solder : Time, one of our big concerns was battery life. We knew that we would need a RTC and some
type of micro-controller. After experimenting with a bunch of different RTCs we decided to go with the Dallas Semiconductors
. This
RTC clock runs at over a range of voltages which included our required voltage of 3v. It has extremely low current when in standby mode and
uses I2C to communicate with the master micro-controller.
For the micro-controller we chose the PIC16F631 . This IC has only a few peripheral functions built in (with keeps the cost down), and since we
didn’t need many this also saves some power. The PIC16F631 has a very low power sleep mode, has enough pins for our project (and only one
spare one), and also runs at 3volts. The PIC16F631 does not have built in I2C, so we used a
bit banged version to control the RTC.
Battery Life: