Hardware Reference
In-Depth Information
Connecting the PIR
I will now show you how to connect and use the PIR. I'm sure you will notice a lot of similarities with the pressure mat.
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you may have noticed that your pir came well wrapped and even stuck into some antistatic foam (well,
i hope it did anyways). unlike other sensors throughout this topic, the pir is quite sensitive to static. as you may know by
now humans are very good at retaining a high amount of static electricity so be careful.
Caution
There is not a lot to the PIR circuit; in fact it's just two resistors. For this project I recommend that you either
solder a length of wire to the PIR or mount it on a secondary breadboard because to test the PIR you're going to need
to do two things at once:
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Being in front of it
•
Typing on your keyboard
This leads to the PIR always detecting you and as such you also need a good way to hide the PIR from yourself.
With that in mind let me show you the electronic schematic for the PIR. In Figure
5-12
you can see how simple the
circuit really is. Maybe this should have been the first chapter: it's that simple!
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Figure 5-12.
The PIR schematic
