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| For ease of development, they also get a serial interface ("FTDI cable" -- power supply + RX/TX + reset, also for flashing using a boot loader). | | For ease of development, they also get a serial interface ("FTDI cable" -- power supply + RX/TX + reset, also for flashing using a boot loader). |
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| == Implementation ==
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| Both for development and for the final version (as far as we know now), an ATMega328 is used; for development, encased in an Arduino, which also binds the RX/TX pins to a USB serial interface.
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| As an RF module, RFM12B is used.
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| The wiring is defined in an eagle file [http://github.com/Metalab/hsc2011/tree/master/hardware in the project repository].
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| === RFM12B ===
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| A little very unprofessional test showed that with the current configuration (through-hole mounted RFM12B with the wire antennae bent to the opposite direction of the pins) with a sender at the whateverlab solder stations a receiver starts losing 6-long packets some steps outside the metalab door front and in the library. Even without further optimization, that should be sufficient for typical class rooms.
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| Experiments showed that sending a login packet takes about 10ms.
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| [[Kategorie:HSC2011]] | | [[Kategorie:HSC2011]] |