annotate hw/README @ 11:d3b5e4251950

Use COUNTER not DERIVE (duh)
author Daniel O'Connor <darius@dons.net.au>
date Mon, 25 Nov 2013 23:43:17 +1030
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children b4de1b6f8f78
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1 The schematic is designed using TinyCAD
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2 http://sourceforge.net/projects/tinycad/
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4 The stripboard was laid out using VeeCAD
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5 http://veecad.com/
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7 It is loosly based on an Elektor circuit
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8 http://www.elektor.com/magazines/2002/march/iec1107-electricity-meter-interface.55617.lynkx
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10 The photodiode is an OSRAM BP104, the IR LED a generic IR LED from Jaycar
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11 (ZD1947) with a spectral peak of 940nm. The opamp is an LM348 clone (ZL3348 from Jaycar).
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13 The 6 pin interface is a TinyOS FTDI breakout
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14 http://www.tinyosshop.com/index.php?route=product/product&product_id=186
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16 Mine is running at 5V but it works at 3.3V.
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18 I needed to use the FTDI EEPROM tool to invert the TX & RX sense using FT_Prog from
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19 http://www.ftdichip.com/Support/Utilities.htm
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21 The need to invert could be rectified by modifying the circuit, but modifying the
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22 EEPROM was a lot easier than changing the circuit.
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