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Sun Oct 6 11:31:21 EDT 2013

- an improvised connection for in-circuit programming. Later on,
  this will be replaced by a "bed of nails" that connects directly
  to the test points.

- battery and switch, not yet mounted. They're both huge and make
  soldering other things more difficult, so they'll go last.

- the MCU

- Micro USB AB. The connector looked intimidating because the
  signal pins are hidden under the shell, but turned out to be easy
  to solder. Not tested yet. I also didn't populate the ESD

- memory card holder. The geometry of this one needs checking. Some
  of the pins almost miss their pads. I think I managed to get
  everything connected, though. Not tested yet.

- lanyard hole. The PCB around it looks quite fragile ... and it
  is, since that bridge that should be about 1 mm ended up being
  only some 0.5 mm. Have to tweak some milling parameters. In any
  case, this isn't supposed to be a load-bearing element.

Here's the top side:

At the bottom, one can see a Freescale FRDM-KL25Z that I use as
programmer for now. On the Anelok, only two groups of components
are populated:

- the LED

- transceiver with crystal. It can't do much without the actual
  RF parts (balun and a few caps) but this already allows me to
  check that the chip comes up and that the crystal oscillator

I've written a few lines of test firmware to blink the LED:

The next steps are to add the boost converter and the rest of the
power circuit (reverse polarity protection FET, memory card power
gate FET, silo cap for RTC in deep sleep). But that's for another
day :-)

- Werner

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