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revolution
Revolution Education Ltd. Web: www.picaxe.co.uk
Version 1.3 04/11
AXE401.PMD
AXE401 PICAXE-28X2 Shield Base
1.3 What does open source hardware mean?
It means we publish the shield base circuit schematic and PCB layout free of charge
on our website. You can modify the PCB and build your own new PCB derived from
it if you want to. You can also even download completely free PCB software (e.g.
Eagle or DesignSpark) to do these modifications and generate new Gerber files!
However as this product is also a ‘not for profit’ PCB, it is highly unlikely that a
prototyping company could produce a PCB cheaper than we will sell you one!
1.4 What does ‘not for profit’ PCB mean?
As the name suggests we manufacture, stock and sell the unpopulated
shield base PCBs at the lowest cost possible. A nominal handling
charge is added to cover warehouse processing costs, but this is
deliberately kept to a minimum. We can afford to do this as the
shield base is just one item within a large range of PICAXE
development project boards and chips, so by buying this permanently
low priced ‘promotional’ shield PCB we hope you will consider
purchasing further PICAXE microcontrollers and project boards in the
future.
We will post the PCBs anywhere in the world by Airmail at a nominal postage cost.
1.5 PICAXE-28X2 microcontroller
The shield base is designed to work with the PICAXE-28X2 microcontroller, which
is based upon the Microchip PIC18F25K22-I/SP microcontroller. Other PICAXE
chips are also available in 8, 14, 18, 20 and 40 pin formats, but these other sizes
will not fit on the shield base as they are a physically different size.
1.6 Do I have to use the shield base to use the PICAXE system?
No, not at all! In fact the only normal reason to use a shield base is to integrate
with an existing third party shield (e.g. MP3 player shield or Ethernet controller
shield). If you want to build a project yourself from scratch it may well be cheaper
and easier to use one of our many PICAXE project or proto boards instead,
particularly if you could use a physically smaller, lower cost 8 or 14 pin chip such as
the PICAXE-14M2 instead. Or just buy a PICAXE chip by itself and build your own
breadboard/stripboard/PCB circuit. The choice is yours!