Hey and welcome to our Ultimate Triggertrap Arduino Shield page. On this page, you will learn what the different parts of the Triggertrap Shield are, and we’ll show you how to assemble your own.
What is a ‘shield’? How does it work?
The Triggertrap Shield for Arduino is a fully featured Triggertrap, except with a couple of differences. For one thing, you have to have an Arduino in order to use it: This version of the Triggertrap is a ‘shield’. Basically, that means that it rides ‘piggyback’ on an Arduino rapid prototype board. This is great, because you can use your Arduino for all sorts of awesome projects. When you want to use it as a Triggertrap, simply load the Triggertrap software onto the Arduino, place the Triggertrap shield on your Arduino, and you’re ready to go!
The Triggertrap Shield is a great project for everybody who wants to learn more about electronics, too: It’s relatively easy to build, and we’re providing you with full instructions for how to do it on this page. We’ve been contacted by high school electronics teachers, after-school electronics clubs, and more than a few dads (and one mom, too! Go electronics moms!) who all wanted to use the Triggertrap to teach their kids/students/themselves more about electronics. Awesome!
If you ended up here by accident, and are looking for somewhere to buy the shield, try the Triggertrap Shop!
Table of Contents:
- What is a shield? How does it work?
- Table of contents (you’re looking at it…)
- Which Arduino works with the Triggertrap?
- What are all these parts?
- Checking the part list
- Identifying your parts (with photos!)
- Assembling your shield (step-by-step)
- Assembling your shield (Timelapse Video)
- Putting the software onto your Arduino
Which Arduino works with the Triggertrap?
The Triggertrap should work on any Arduino or Arduino-clone that uses an ATmega328 microprocessor. If you have an Arduino, take a close look at the processor chip; it’ll probably either say ATmega128 or ATmega328. You want the latter.
What are all these parts?
When you get your Triggertrap Shield, you’ll find a baggie full of parts, and if you’re new to electronics, that can be a little bit daunting. Don’t worry, we’ll talk you through it. After all, it’s meant to be as much fun building your Triggertrap Shield as it is to use it. So, let’s take you through the parts as they are installed on the Triggertrap Shield one by one. We’ll do that in a video, so I can talk you through it.
Let’s take a closer look, then:
If the video moves too fast, or if you feel like i’m mumbling too much (or if you don’t fancy skipping around to find the one part you’re wondering about), I’ve also created an ‘interactive image’ over on Flickr, which has all the parts marked.
Checking the Part List
Your Triggertrap should come with:
1x PCB (Printed Circuit Board)
1x Momentary Tactile Button (large)
4x Momentary Tactile Button (small)
1x RCA socket (for [AUX] on the PCB)
1x 3.5mm stereo mini jack socket (for [CAM] on the PCB)
1x short length of heat-shrink tubing (for the laser sensor)
1x Optocoupler Integrated Circuit (8 pins, marked with LTV826 – for [IC1] on the PCB)
1x Register Bus Integrated Circuit (16 pins, marked 4094N – for [IC2] on the PCB. This is the one that covers the NoMi logo.)
Sensors and output
1x Laser Sensor Photo Diode (for [LASER] on the PCB)
1x Ambient Light Sensor Photo Diode (For [PQ1 LIGHT] on the PCB)
1x IR Emitter Light Emitting Diode (for [IRLED] on the PCB)
1x LCD display (goes in the pins next between R3 and the Register Bus)
1x Microphone (for [MIC] on the PCB)
2x 510R resistor (green brown brown – for [R1] and [R2] on the PCB)
1x 47k resistor (yellow violet orange – for [R13] on the PCB)
3x 10k resistor (brown black orange – for [R8], [R10] and [R11] on the PCB)
3x 5k1 resistor (green brown red – for [R3], [R9] and [R14] on the PCB)
2x 68R resistor (blue gray black – for [R5] and [R6] on the PCB)
2x 100k resistor (brown black yellow – for [R7] and [R12] on the PCB)
1x 1N4148 diode (for [R4] on the PCB)
*** PLEASE NOTE: In this guide, there are several photos of the Diode installed the wrong way. Please pay extra close attention: When you install the diode into R4, the black markings on the diode should point TOWARD the R3 resistor next to it.
1x MOSFET transistor (marked bs170 – for [Q1] on the PCB)
1x PNP transistor (marked BC548B – for [Q2] on the PCB)
1x 100uF capacitor (for [C9] on the PCB)
11x 100nF ceramic capacitor (for [C1] – [C8] and [C10] – [C12]
1x 8×2 pin header (for the LCD screen)
2x 8×1 pin header (For the LCD side of the Shield)
2x 6×1 (for the buttons-side of the Shield)
Identifying your parts (with photos!)
So, when you are building your Triggertrap, it’s a good idea to use the above list, because it shows both the parts and where they need to go. However, I recognise that some of you may not be completely comfortable with identifying parts by their names, so let’s go through it one more time, this time with photos:
PCB (Printed Circuit Board)
Momentary Tactile Buttons (large and small)
3.5mm stereo mini jack socket
Short length of heat-shrink tubing (The one you get will be a little shorter than this)
Optocoupler Integrated Circuit (marked with LTV826)
Register Bus Integrated Circuit (16 pins, marked 4094N)
Sensors and output
Laser Sensor Photo Diode (note the absence of tabs on its legs) – it will also come in a baggie marked ‘Laser Sensor’, so that makes things a bit easier.
Ambient Light Sensor Photo Diode (note the little tabs on its legs) – this one will come in a baggie marked Light Sensor.
IR Emitter Light Emitting Diode (Note it faces sideways)
Resistors & Diode
Resistors look like this; refer to the color codings in the parts list to know which is which.
There’s also one Diode, which looks like this little fella.
MOSFET transistor (It’ll be marked with bs170)
PNP transistor (marked BC548B)
100nF ceramic capacitor
Pin Headers look like this. In your Triggertrap Shield kit, they should already be cut to the right sizes for you.
Assembling your shield (Step-by-step photo guide)
First of all, start by making sure that you have all the parts, and that they are easily available. Call me a n00b, but I quite like doing it like the above: All the parts neatly arranged (click on that image for a higher resolution version of that photo, if you’d like to take a closer look.
Right, the fun all starts with the PCB. This is the base for all the components, so spend a bit of time looking at it…
… From both sides. On this side, you’ll see that all the components are outlined.
And if you take a closer look, you’ll see that all the components are marked with numbers, such as R8, C4, IC2 etc. Now, if you remember back up there on the parts list, I listed all the different parts, and where they go on the PCB. Your job, in assembling this board, is going to be pretty easy: Match the right part with the right place on the board, and simply solder them in place! Simples!
Before you begin, there’s a couple of additional things you’re going to need:
- A soldering iron. You don’t need a fancy one, but since we are working with integrated circuits, it’s a good idea to get one that doesn’t get too hot.
- Some soldering tin. Lead free, if possible; lead fumes aren’t good for your brain
- Some soldering skills. If you’ve never done this before, head over to the fabulous article How to Solder over on Instructables, and fill your boots. It is probably a good idea to try to solder a few things before you attack the Triggertrap shield, but to be honest, I’m a complete soldering novice myself (this project is the first time I’ve ever soldered IC’s, for example), and it isn’t particularly difficult.
- A pair of wire cutters, to cut off the excess metal from the parts you’re soldering in.
- Needle-nose pliers, because these parts are tiny, and sometimes pliers are better than fingers.
- Some anti-static measure. I use a wrist strap that’s connected to ground. Some people also work on an anti-static mat as their surface. Always a good idea, but I haven’t got one here in Argentina, so I’m using my wrist strap and keeping my fingers crossed.
Right, let’s get started. It doesn’t really matter what order you use to get the components soldered in place, but I find it easiest to start with the lowest-profile components. That way, you can place them in the PCB, and flip the whole thing over; when you do, the table holds the components in place as you solder them. Simple! Since the capacitors are the smallest, I’m going to start with them…
Capacitors – the small capacitors we use can be soldered in place either direction. The big capacitor ([C9]) needs to be soldered in a particular orientation, but we’ll get to that later.
Bend the legs so they make an ‘U’-shape, and stick both legs through the PCB.
As you stick any component into the PCB, check the following:
- Is your component in the right place? (check that you have the right component for the right number on the PCB).
- Is your component in the right place? (check that you have the right component for the right number on the PCB). Yes, check it twice.
- Is your component the right way around? Some components can only be soldered in place one way, because that’s the way the components work.
When you’ve placed a few of them into the PCB, flip it over. I like to bend the legs outward a little bit, so they are held in place easier, as you can see from the images above.
Now, simple solder them in place, using your finest soldering skills…
Look at those beautiful tiny little solder points! Beautiful.
And when you’re done soldering, cut off the extra lengths of the legs of the components with some wire cutters.
Will you look at that! All the little yellow capacitors are in place. Fabulous. With a bit of luck, yours will look neater than mine, too.
Time to add the resistors.
Resistors: There are a whole load of them, and they all have different values, so make sure you double-check the resistor values. Resistors can go into the PCB either direction.
All the resistors are in place. Beautiful!
One thing to be aware of:
The socket marked [R4] is not a resistor. it’s a diode. Diodes are directional (that’s kind of the point of them), so make sure that the dark side of the diode points towards the resistor next to it, like in the photo above.
Right, now, let’s add the first fun part to our PCB: the ambient light sensor! It goes into the hole with the little circle, marked PQ1-LIGHT.
Heads up: This component is directional, and it can look very similar to the laser sensor, but they are different, so don’t get them mixed up!
The ambient light sensor has little tabs on the legs, and has an angular shape inside.
The ambient light sensor has to be placed into the PCB with the angle ‘pointing’ toward the PQ1 Light text on the PCB.
Place it into its socket, solder it in place, and cut off the excess legs as you have been doing with the other components.
Time to do the laser sensor. This one is a little bit more tricky, because we’re going to solder it in place first, and then bend it so it’s laying down. Make sure you give it a couple of mm extra space.
Again, you will probably only have one of these left now, but to identify the laser sensor, check this out:
The laser sensor has a little ‘anvil’ shape, rather than an angle. The top of this sensor makes a little arrow (in this picture, it is pointing to the right). This little arrow needs to point away from the ambient light sensor you just installed – be careful to get it the right way around, because if you put it in the wrong way, it won’t work! To clarify: The cathode – that’s the short leg of the laser sensor – should be on the side of the ambient light sensor.
Now, to make sure the laser sensor is purely directional, we’re going to block out all the other light. Find the little piece of black tubing. It should be about 14mm in length – but don’t worry if it is a little bit longer. I’m cutting of a piece here because mine is longer than it needed to be.
Simply slide the heat-shrink tubing over the laser sensor like this… and it should now look a little bit like this:
Use your soldering iron to ‘pet’ the heat shrink tubing carefully. You’ll notice it shrinks in size, and starts ‘hugging’ the sensor. That’s what you want – brilliant! Make sure it covers the bottom of the sensor as well – the only opening you want is the one at the top.
Now, simply bend the sensor down (carefully!) towards the PCB.
When it is bent into place, it should look a little bit like this
Mine was still a little bit too long, so I trimmed it to the edge of the PCB – but you don’t really have to do that.
Next, I’m going to install the two transistors. These have to be placed onto the PCB in a particular way, but if you take a look at the white markings, you’ll see it’s pretty obvious which way they should go.
Bend the middle leg backwards, and place the two remaining legs in parallel. All three legs go into your PCB, like this:
Now, the two transistors can look similar, but they are not the same – take extra special care that you have the right transistor in the right place.
The NPN transistor will be marked with BC548B, and goes in [Q2].
The MOSFET transistor will be marked with 2N 7000, and goes in [Q1]
Solder them both as usual, and trim off the legs.
Right, your PCB should now look a little bit like this!
Let’s add in the IR transmission LED as well. This one is also directional, but it’s sort of obvious which way it needs to go: One side has a little bulge on it, which needs to point outwards.
Next, put the microphone in place. Again, it should be soldered in the right way around, but it’ll be obvious from the white markings which way it needs to go.
Now, let’s do the last capacitor. As you may have remembered, this one is directional. The PCB has both + and – marked on it, so simply take a closer look at it. One of the legs will be clearly marked with + or -, so simply make sure it’s pointing the right way, and place it through the PCB.
To minimise the height of our Triggertrap shield, we’re going to bend this one, much like we did with the laser sensor, so leave about 3mm worth of extra room for the capacitor to bend.
Place it through the PCB as usual. Solder it into place, but don’t cut the legs yet!
Carefully bend the capacitor down . If it lays down neatly like this:
Good job! now you can cut the legs off it. If you didn’t get it quite right, simply loosen the solder again, pull the capacitor up a little, and try again.
Now, let’s add the buttons. These can go into the PCB either direction, and should simply click into place. Apply gentle but firm pressure to the buttons, and you’ll feel them click into their sockets neatly.
When they are all in place, flip the board over, and solder them so they stay put.
Be-a-utiful! This is starting to look an awful lot like a Triggertrap Shield!
Now, we’re going to add the 3.5mm socket. You’ll notice that this one doesn’t have any legs; that’s because it’s a SMT component; or Surface Mount Technology. A lot of hobbyist electronics tinkerers seem to be afraid of these things, but trust me, there’s nothing to it. Simply align the little notches at the bottom of the socket with the holes in the PCB…
And add a little dash of solder on top of the pads. Because the PCB is pre-treated, you should see that the solder flows gently, leaving beautiful, square blobs of solder, and the device firmly in place. How awesome is that?
When it’s soldered in place, it should look a little bit like this. Gorgeous.
Next, I’m adding the RCA socket. It’s a bit chunky, so you may use a little bit of force to get this thing to go where you want it.
When it’s there, simply solder it into place. Remember that you don’t have to fill the solder holes completely; simply make sure there’s a good connection between the RCA socket and the PCB.
And you’ll end up with something like this. Smooth job.
Now, sit back and pat yourself on the back. Only a few components left to go!
The next thing we’ll be putting into place is the register bus. This needs to go into the socket in a particular direction, there’s a small D-shaped notch at one end of the chip. Match that notch up with the same notch that’s marked on your PCB, and you can’t go wrong.
Hold the Integrated Circuit (IC) firmly in place, and bend one of the legs in each end so it is held in place. It makes it easier to solder it.
Now, when you are soldering IC’s, bear in mind that they can be heat sensitive, so you don’t want to hold your soldering iron on the chip for ages. Light and quickly does it, and try to use only as much solder as you need:
Just like with the camera socket, the pads on the PCB are treated, so you should see the solder flow in beautiful, oblong little shapes. Cool, eh?
Gorgeous. Good work.
Now, let’s add the Optocoupler. This one also has to be soldered in in a particular direction. Do you see that little white dot next to “Aref” on the PCB? Your opto will also have a little dot on it. Place them next to each other, and that’s the direction it needs to go. Easy!
Good stuff. Again, I’m using the same trick with bending one leg on each end of the chip to hold it in place, and then I”m carefully soldering it into place.
Now, let’s add the pin-headers that connect the Triggertrap shield to your Arduino.
The easiest way to make sure that the pin headers perfectly match up, is to grab an Arduino, and use it as a template. Also in this photo: My rather awesome carbon fibre ring.
So, place the pin headers into your arduino…
… Should look a little bit like this.
Carefully place the shield over the arduino, and make sure all the pinheaders align with the holes.
Push it down into place. Perfect!
Now, simply solder all the pinheaders into place.
And the final result should look a little like this.
Now, take the shield off the Arduino, carefully.
Congratulations, you now have an Arduino shield!
The final step is to add the remaining pinheaders into the LCD screen…
… And to solder the screen into place on the Triggertrap Shield.
Now, go get yourself a cold beer. You deserve it.
Assembling your Shield (Video)
I am still looking at creating a full-on instruction video; for now, I think the step-by-step photographic guide is probably easier to follow. Below, a timelapse where my head is in the way of the camera a lot (sorry!)
Grab the software
The final step is to get the software for your Triggertrap Shield for Arduino. It’s open-source, of course, and available from Github. You can either download it or fork it, and then just upload it to your Arduino the way you normally do.
If you’re having problems, it’s down to the Arduino in this case, so check out the Arduino FAQ for more information!