Regulate Temperature with a Raspberry Pi Pico — Part 2: Assembly
In Part 1 of this article series I showed you what hardware components you needed to build a temperature regulator, that can control two relays. In this next part of the series I will show you how to assemble all of the hardware components together.
We will assemble the components in the following order:
- Expansion Board and Pico Microcontroller
- Pico HATs (Dual Relay and OLED Display)
- Breadboard, Temperature Sensor and Resistor
- Breadboard and Expansion Board Wiring
Expansion Board and Pico Microcontroller
Take and expansion board and the Pico microcontroller, paying close attention to which side the micro USB connector is on. On the expansion board itself you should see an image indicating which side the micro USB connector should be:
Carefully slot the Pico onto the expansion board:
NOTE: Most expansion boards should at least show the number of each pin in case there is no image of a micro USB connector.
Pico HATs
Next take the Dual relay HAT and the 1.3" OLED Display HAT, again paying close attention to which side the micro USB images are on:
Carefully slot the Relay HAT and Display HAT onto the expansion board:
NOTE: It doesn’t matter which expansion slot you use on the expansion board, so long as the HATs are facing the correct way.
Breadboard, Temperature Sensor and Resistor
What we want to do is connect the temperature sensor and resistor on the breadboard as per this wiring diagram:
The wiring on the breadboard should look similar to this:
Breadboard and Expansion Board Wiring
Next connect three jumper wires (Black, Yellow, and Red) onto the breadboard, corresponding with the sensor wires as shown here:
Then on the expansion board connect the jumper wires as follows:
- Connect the Black wire onto a ground (-) pin
- Connect the Red wire onto a 3V3 (+) pin
- Connect the Yellow wire onto a GP16 (16) pin
NOTE: Some of the GPIO pin numbers are used by the HATs by default, so we’ve chosen a specific GPIO pin number (16) for the temperature sensor so it doesn’t clash.
The wiring should look similar to this:
Finally we can connect the micro USB to USB cable, to the Pico microcontroller:
In Part 3 of this article series, I will show you how to copy the required code files from my GitHub repo onto the Pico microcontroller to make it all run.
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