.. _pic-devboard:

PIC Prototyping Board
=====================

:date: August 1, 2010

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Designing a simple microcontroller prototyping board has been on my TODO
list for while now. With my new :ref:`PCB Fab Lab<pcb-exposure-box>`
established, I was finally able to start the project.

Design
------

The design was focused on producing as small a board as possible. The board
had to faciliate programming and smooth operation of the microcontroller,
while keeping most of the I/O pins available for use.

Even though the board is simple, routing consumed quite a bit of time. The
main reason for this was that the design was restricted to a single layer.

The board uses a PIC18F4550 microcontroller. USB socket is used for power
as well as programming (bootloader required). DPDT switch allows to choose
the source of power - USB or external.

Here is a 3D image of the board, rendered during development.

.. image:: static/pic_3d.png

Results
-------

Here is a video of a test run:

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.. figure:: static/pic_dev.jpg

   The board next to a PICkit 3

Links
-----
   * `Schematic diagram <static/devboard.pdf>`_
   * `PCB layout <static/devboard_pcb.pdf>`_