We'll start with an assembled SmartMatrix Shield. For the pictures in this guide we used a SmartMatrix Shield with female connector to plug the Shield directly into the panel, the terminal block power option, and we added the diode and cut the Teensy VUSB trace to power the Teensy from the external power supply. You can use the other assembly options listed in the SmartMatrix Shield assembly instructions if you prefer.
To make for a lower profile install, you might want to swap out the straight male pins for the expansion header with right angle pins if you have them, like we did in this guide.
Refer to the instructions here to assemble the shield.
If you want to install the optional microSD card for playing animated GIFs, refer to the instructions in the SmartMatrix Animated GIF Player guide. Follow all the instructions in the tutorial and make sure you are able to play GIFs. The Arduino sketch in this tutorial will read GIFs from the same directory on the microSD card.
You can insert the three pins of the IR sensor into the the female-female Jumper Wires, but the connection will likely be a little loose.
To make for a more secure connection, use needle nose pliers to bend the end of the sensor pins back on themselves to double up the thickness.
After the ends of the pins are bent back, use the pliers to flatten the ends out as much as possible.
Now when you insert the pins into the jumper wires, the connection will be snug, and it may not be possible to pull the pins out again without damaging the jumper wires
You may need to use the pliers to push the sensor pins into the crimps on the cable as it's now a tight fit.
The sensor connects to power (3V3), ground, and the IR signal connects to an input pin (18). Use the rounded side of the sensor and this picture to identify the three pins.
Connect the sensor to the SmartMatrix Shield, and mount the sensor with the dome side facing out so it can receive signals from the IR remote. You can mount the sensor on the side of the panel or in another location it is likely to receive the infrared light from the remote. If you are mounting the panel inside an enclosure, you may want to use a longer cable to bring the IR sensor out of the enclosure. I used black gaffers tape to mount the sensor in the picture.
If you added a microSD reader following our earlier tutorial on the SmartMatrix Animated GIF Player, you will find the 3V3 and GND pins are already occupied. You could make custom cables to share the 3V3 and GND pins with two other connections, but that's a lot of extra work. Instead we will use the AGND pin in place of GND, and the VIN pin instead of 3V3. AGND connects to GND inside the Teensy 3.1 through an inductor. VIN will be between 4-5V instead of 3.3V, but both the Teensy 3.1 and IR sensor are 5V compatible, so there shouldn't be any problem running the sensor from VIN.