2017-10-28 21:42:28 +02:00
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# TinyFinger
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2017-12-01 02:00:58 +01:00
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TinyFinger is a small device powered by an ATtiny45 to produce pseudorandom
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2017-10-28 21:42:28 +02:00
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numbers for selecting student groups during the computer science hardware
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courses at Leipzig University.
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## board
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The board is designed in KiCad and uses a single sided pcb layout using
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mostly SMD components. The routing was done manually.
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## code
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The firmware for the ATtiny is written as an Arduino sketch using the
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2017-12-01 02:00:58 +01:00
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[ATTinyCore] board definitions. It uses a [linear congruential generator]
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2017-10-28 21:42:28 +02:00
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for generating pseudorandom numbers and transforms them to the needed
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range using the gcc uniform_int_dist c++std implementation.
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2018-03-01 08:02:48 +01:00
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Flashing the firmware can be done using a usual Arduino programmed as an
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ISP with the ArduinoISP example sketch included in the IDE. Then the Arduino
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can be connected for example via its ICSP pins:
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![ICSP]
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The pins on our TinyFinger board are from left to right:
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GND, MISO, VCC, SCK, MOSI, RESET.
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2017-10-28 21:42:28 +02:00
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## case
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The case is modelled in Blender and intended for 3d printing, e.g. using
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Cura after exporting the model as an stl file.
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2017-12-01 02:00:58 +01:00
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[ATTinyCore]: https://github.com/SpenceKonde/ATTinyCore
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2017-10-28 21:42:28 +02:00
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[linear congruential generator]: https://en.wikipedia.org/wiki/Linear_congruential_generator
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2018-03-01 08:02:48 +01:00
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[ICSP]: https://www.arduino.cc/en/uploads/Tutorial/ICSPHeader.jpg "Arduino's ICSP pins"
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