homebrew processors and film camera love

Make Your Own – Part 2 – Temp Setup

Make Your Own – Part 2 – Temp Setup

The Theory

The smaller arduino uno, takes the temperatures of the two chemicals, via the DS18B20 temp sensor setup. This is then displayed on the relevant 4 digit display and updated every second. Once the chemicals reach a certain temp, then the arduino sends a pin output signal over a wire to the other arduino. (I have 2 wires, for 2 different temps, eg. one for Mono, one for c41)

Rough Setup Guide

Firstly, setup a standard twin sensor DS18B20 setup on a breadboard with the resistors and connect the Onewire setup to Pin 2 on the Uno. Below is a helpful guide to show the wiring.

This diagram is generic, Green should goto Pin 2, the Red to 5v and the Yellow To Ground

Now get your two 7-segment 4-digit displays and wire them in as the Pin guide, attaching the 5v and GND pins as well

3-Display 1 CLK Pin (Water temp display)
4-Display 1 DIO Pin
5-Display 2 CLK Pin (Chemical temp display)
6-Display 2 DIO Pin

Now open up Arduino IDE on your PC and connect the Uno. You will need the following libraries to get the above to work.

#include <OneWire.h>
#include <DallasTemperature.h>
#include “SevenSegmentTM1637.h”
#include “SevenSegmentExtended.h”

Now to get it running, copy and paste the Temp Arduino code and compile/upload it. If you get any errors, you might need to google them, if you have slightly different setup/hardware.

You should then hopefully have two displays showing the temps of the sensors. If you are getting zero, then you might need to troubleshoot your temp sensors using basic free code off the net.

We will ignore the Pin outputs 8 and 9 for the minute until we get the other bit working as its alot more complicated.

Hopefully you should have something looking like this now, well done if you have, thats the first part done.

Image showing temp setup, the sensors aren’t in view.