I've managed to build a RPi project to control and monitor some aspects of my aquarium.
Some time ago, while a rev1 model B RPi was connected in this project, but not doing anything in particular apart editing a text file, it suddenly died. I talk about this in the thread @ http://www.raspberrypi.org/forums/viewt ... 28&t=87982.
I replaced it with a model B+, modified some things and had another go.
After that, I had to move the root filesystem to a USB stick, due to the corruption of the sdcard.
For the 3rd time now, I'm up and running again. I hope this will last.
Basically in this project, I use:
- 3 GPIO pins (17, 27, 22) connected to an ULN2003A and a 12V line to do PWM towards a Led strip and a fan;
- 4 GPIO pins (18, 23, 24, 25) to switch 4 single relay boards via 4 opto-isolators "modules" I've built;
- GPIO pin n. 4 (1-wire) to two DS18B20 probes;
- Real Time Clock via I2C.
I tried to write down the connections with KiCad.
[see next post]
In this schematics I didn't include the "mains" wiring, but it's really simple: just 4 sockets closed by the 4 relays, plus the wiring towards the two power supplies, 12V and 4,5V. We talked about the relay part here: http://www.raspberrypi.org/forums/viewt ... 37&t=85681
Any feedback is more than welcome,