Still very busy with the maker faire builds, and upgrading my 1.0 builds . Last week I finished the all in one controller (details are couple of pages before in this thread ), this week it was power controller with hdmi connector and three temperature probe (remember 2.0 aims to support multiple temperature sensors) . This build will be used to 2.0 code that’s going through development right now
This is the first time I am ussing sainsmart recommended wiring to connect to relay, which is basically gating each gpio with a npn transistor. I don’t know if this is required, but it’s probably a good practice. Also, since this build will have the AC 110V components separate (connected via an hdmi cable ) I think the current draw will be higher and the npn ransistor will pay off.
Close up of the npn crcuit (each transistor represent one gpio input)
Since my last build , I am not tying out this pattern of stacking pi on top of proto board (gikfun) . Pi itself is connected to a adafruit perma proto board. Together this gives me a stackable configuration, with solid core jumper wires as connecting mediums
Here is the perma proto board wiring
Perma proto board is then stacked on proto board
Proto board is fixed on the housing (uxcell project box) with nylon m3 screw and nuts and standoff’s (
amazon has them for 5$)
Hdmi connector is not yet hooked up(will do that as part of the other build invoking relay and ac receptacles ). Notice there are three Audio connectors for temperature sensors, they are all connected to a single one wire bus/gpio 4 with 4.7k pull-up ), this is what I’ll need to test the 2.0 feature
End result m