In this lecture, I'm going to walk you through the circuit schematic for the Tyrolean controller of
this project, and of course, I have drawn the schematic using Kit Cat and I've also used it to design
the PSP that I'm going to show you in a later lecture in this section.
The main component of the circuit and in this schematic is you can see is the death itself.
I am using the kid with the 38 PIN configuration, which is a very common version of the E.S.P 32 deficit.
You can easily find it on eBay or other retailers on the Web on the breadboard.
I have tested the exact same circuit with the 30 pin version of the E.S.P 32 deaf kids.
So you can use whichever you want as long as the pins that you are connecting to the various peripherals
are the same.
So we've got the 38 PIN E.S.P 32 deficit in the middle.
Most of the pins are unused and I'm not exposing them.
Even in the PSP that I've designed again as part of this project that I'm going to talk about in a separate
lecture on the left side of the connectors for the sensors up here on J5 is that the 22 Connector and
Termini is a screw terminal, as you can see from the schematic, using a version of the DHC 22, which
is got a special casing that I can install inside the terrarium and get the air temperature and the
humidity.
So it's got three panes ground.
This is C and I'm connecting the Terrapin to Jupiter 25.
Right.
Then we've got the moisture sensor.
The moisture sensor comes in a module with four pins and I've got a simple header, a female header
on the B itself to which the module is connected to three panes are used.
The second pin here is on use of court and unused mark on it just in case.
At some point in the future, I want to use an environment sensor like the to the BMY or PMP 280 of
made a provision for a connector for this sensor here for the ISO, which the protocol, although I
did not really use it, at least in the current version of the project.
Then you've got a bunch of indicators, ladies, I've got one for the power just to indicate when power
is applied and I've got another couple of these that show me various types of activity.
For example, the circuit will blink these LEDs when there is a temperature, humidity or motor operation
update.
So that can visibly see what is going on.
Now, down here, I've got a couple of circuits, just voltage devices to give me a voltage indicator.
This one here is for the battery and this one here is for the MCU, the microcontroller unit.
Now for the MCU, I've made a provision to be able to power it either from the same power source as
the battery or from its own three point three fourth power source.
So depending on how you want to power the controller, you can just short these two jumpers and you'll
be able to provide appropriate power.
If he's a jumper wire to shorten these two terminals, then you'll be powering your MCU from the external
five-fold pin.
Otherwise it will be powered by the three point three volt pin.
Let's move over to the right side of the dog.
Going to zoom out a little so we can see the whole lot.
OK, here we go.
So there's a couple of different ways to power the circuit.
I've got the barrel jacks, which up here and also crude terminals where you connect motor battery to
the motor battery is meant to provide at least five volts of power, but no more than nine volts, which
will feed directly into the motor.
You can see that the crude terminals here fall is where you connect the motor.
The motor, of course, is what powers the pump.
Alternatively, what you can do is you can also use the same power source that powers the motor to also
power the microcontroller unit.
So there's a jumper here that can enable that connectivity.
Apart from that, whether you use the J3 connector for the motor power source or the barrels, which
is the same thing, you can use one or the other, but of course, not both at the same time.
Below that, we've got the simple circuit for the motor that powers the water pump.
I've got a Shawqi diode here and a small capacitor.
The capacitor is here to try and dampen down any electrical noise that comes from the motor while it's
spinning.
And then this short circuit diode prevents back Karyn's from passing onto the rest of the circuit when
the motor is no longer powered by just is free spinning as it's slowing down.
That could produce current, that can damage other part of the circuit and especially the microcontroller.
So you've got this diode here to prevent that from happening.
And then down the bottom of this part of the circuit, we've got a tip.
One hundred and twenty two transistor, which I'm using as a switch.
The combination of the 330 ohm and the 20 kilogram pulled down resistor right here allow us to turn
this switch on with a very small amount of Charente coming from Tapio three to.
And that's about it with this circle, as you can see, it's fairly simple, you can easily implement
it on a breadboard or you can go for a proper piece of be designed.
That is, as I said, and I'm going to show you what that looks like in a later lecture in this section.