For the main processor,you will need a Feather M0 Bluefruit BLE. This will allow you to do switch control on an iOS device such as iPhone or iPad. If for some reason you choose not to do the BLE switch control, you could substitute a different Feather M0 or M4, however IRLib does not support nRF52832 or nRF52840 devices, so that is not a viable option.
For display, the 2.4 inch TFT FeatherWing is used.
Although the Feather has a built-in charger, we decided not to use it. Instead we are including a Power Boost 1000c. This allows you to keep an iPhone or iPad charged using the remote's battery. It's not sufficiently powerful enough to charge a dead iPhone or iPad while simultaneously running the remote, but it does keep the device topped up if it is already charged. On a normal day, I have no trouble going all day without recharging. If I am going to do live streaming on the phone or shooting lots of video, I sometimes need to recharge or plug-in a supplemental battery.
To preserve your battery life if you are not using the device for a long period and not charging it, you should have a power switch.
In my day-to-day usage of the device, I plug it in every night. After a while, the micro USB B connector on the power boost failed even though it is one of the most sturdy micro USB connectors I've ever seen. To make it easier to charge the device, we include a 2.1 mm barrel jack as an option.
This 4400mAh Li-Ion battery will provide plenty of power to operate the remote all day long and to keep your iPhone or iPad topped up.
We will assemble the case using M3 brass heat set inserts such as these below. You also need four M3 screws. We recommend flat head Phillips screws but rounded screws of any kind would work as well as long as they are M3 size. They are available from a variety of sources including your local hardware store or from this or other online suppliers.
These heat-set inserts will be melted into the 3D printed plastic case. We recommend you obtain one of these adapters for your soldering iron that will make it easier to press these inserts into place.
Although we prefer the brass inserts and the M3 screws, we also provide an alternative case that can be fastened together with #6-20 sheet metal screws which can be obtained from hardware stores or the source below. When not using the brass inserts and the M3 screws, we prefer sheet metal screws over machine screws because they have a pointed tip that taps into the plastic rather well.
The TFT display mounts into the case using four 2.5 mm screws. It could also be attached to a case using hot glue or CA glue. Additionally, you will need glue to attach the 2.1 mm barrel jack into the case. We will also secure the battery in the case using tape or hot glue.
The case is designed with a 1/4"-20 T-nut that makes it easy to mount the remote on any 1/4"-20 camera mount or other such bracket. We use one that is 3/4" diameter with 4 prongs. Here are 2 sources or you may find them at your local hardware store. Alternatively you can come up with your own mounting system. Mine is mounted with Velcro onto another bracket.
The Receiver
If you're going to use the device to emulate mouse or keyboard on a PC or laptop, you will need to create a receiver dongle using a Trinket M0.
You also need a TSOP infrared receiver such as this one for the dongle.
You will also need an IR transmitter board which is described separately in the link below. It will have its own parts list. The IR board has a number of assembly options so you should also see the section in this tutorial titled Infrared Board Assembly for more details.
Connections to Other Devices
A variety of techniques can be used to activate this device. In this tutorial, we will describe how to connect 3 assistive technology (AT) switches using standard 3.5 mm (1/8 inch) mono jacks. You can obtain such jacks at this link.
Wiring it all up
Finally, you will need connecting wire. A soft silicone stranded wire will be handy to use in most instances, however some of the wires will have to be solid-core because they need to plug-in to the socket of the TFT display board. Alternatively, you can use a soft silicone wire and solder on a piece of stiff wire or a single pin header. It's good to use a variety of colors so that you can keep things sorted out while you are working on the device and troubleshoot any mistakes easily.
