--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hw/README	Wed Nov 20 23:26:45 2013 +1030
@@ -0,0 +1,23 @@
+The schematic is designed using TinyCAD
+http://sourceforge.net/projects/tinycad/
+
+The stripboard was laid out using VeeCAD
+http://veecad.com/
+
+It is loosly based on an Elektor circuit
+http://www.elektor.com/magazines/2002/march/iec1107-electricity-meter-interface.55617.lynkx
+
+The photodiode is an OSRAM BP104, the IR LED a generic IR LED from Jaycar
+(ZD1947) with a spectral peak of 940nm. The opamp is an LM348 clone (ZL3348 from Jaycar).
+
+The 6 pin interface is a TinyOS FTDI breakout
+http://www.tinyosshop.com/index.php?route=product/product&product_id=186
+
+Mine is running at 5V but it works at 3.3V.
+
+I needed to use the FTDI EEPROM tool to invert the TX & RX sense using FT_Prog from
+http://www.ftdichip.com/Support/Utilities.htm
+
+The need to invert could be rectified by modifying the circuit, but modifying the
+EEPROM was a lot easier than changing the circuit.
+