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by StavrosK 4911 days ago
I recently discovered you can use the pins on the Raspberry Pi to programmatically toggle switches! As a software guy, I find that magical. I ordered a cheap 8-relay board [1], and I'll hook some stuff up to it and turn my house devices on and off via the internet!

[1] http://dx.com/p/8-channel-5v-relay-module-extension-board-fo...

1 comments

Not to burst your bubble, but Raspberry Pi IO pins operate at 3.3 volts, and the board you linked requires 5 volt logic inputs. It might still work, since there are no specs available for the transistor on the board, but don't count on it!
The Raspberry Pi provides a 5V out pin at ~ 300 mA, so it should work, if the transistor works at 3.3V. Also, someone has tried it, and it worked. I just hope it's the same board.
FYI, It's ok to output at 3v3 volts to a 5v device if the device will still work, but don't read input from a 5v device or you might damage your Pi; the pins are wired directly to the Broadcom chip with no resistance.
Oh, indeed, thank you. I don't have anything to read at the moment, but I'll keep it in mind!