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by Phillip Pearson.
Original Post: Home automation notes
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The PIC16F628 seriously fails to suck. All the features of the 16F84 and then some, and US$1.80 each for 25+ at Digikey. By the time a batch of 25 would make it to New Zealand, that's about NZ$5 each. I may be out of date, but this seems about 20-50% of the cost of comparable AVR chips. They don't look as efficient or easy to program as the AVRs, though. [The AVRs execute one instruction per clock, and I built a parallel cable to program them a while back that only needed two transistors.]
OpenPic.Net is a complete DIY home automation system that uses the 16F84. It's controlled by a PC, and uses a star-connected serial bus for communications (very simple protocol, at about 500 bps).
Now what I need is a slightly safer / better equivalent of the OpenPic.Net switched power plug. I don't like the look of the solid-state relays they're using; I'd prefer an optocoupled magnetic relay, to make things less catastropic in case of a fault and to allow switching beefier devices.