Hey everyone!
I want to share a project I'm currently working on - a payload injector with the form factor of a Switch game cart!
As I seem to always forget to bring my phone, cable, OTG adapter or dongle with me, and I'm not a big fan of AutoRCM, I started thinking - wouldn't it be great if I could just store my jig and dongle inside my Switch? I don't really like the idea of opening my switch and soldering to it for warranty/resale reasons, and my card slot is always empty because, well, we live in the age of digital. Thus, DragonInjector was born.
This project is based on the open source Trinket M0 and has three main goals:
1) Everything must fit inside the dimensions of a standard Nintendo Switch game cart. This includes the RCM Jig.
2)
Anything not necessary for the operation of the dongle will be removed for space/power savings. This thing needs to run for weeks on a CR1616. Goodbye LDO, APA-102 LED and always-on power LED! Added the APA-102 and the LDO back after switching the power source to a super capacitor! For all intents and purposes this is now a funny-shaped Trinket M0 and fully compatible with any code written for it.
3) Needs to have a 90's hacker movie name and logo.
I did not want to compromise on usability and convenience, so I deemed the reset button, power switch and status LED as "necessary". The cap for the USB plug will also function as the RCM jig holder. To be clear, this project does
NOT allow you to inject your payload through the cart slot. Without heavy modifications to your Switch this is unfortunately impossible. Here's what it DOES let you do:
- Store your payload dongle inside your Switch game cart slot.
- Always have your RCM jig on you as it's stored in the cap.
- Inject your payload with a USB Type C connector so no adapters are needed.
- Charge it up with the card slot or any USB Type C port thanks to the supercap power source. Charging via the card slot means you can even charge it from the Switch while docked!
- Forget it even exists until you need it.
- One screw holds the board in and removing it will give you access to the SWD and SWC pads so you can reprogram it for whatever you like, including non-Switch stuff if you want.
One nice thing I discovered is that the 3.3v in the game card slot turns off when your Switch is off or in sleep mode, meaning the dongle will charge while you're playing but won't sap your battery when you're not. The average battery drain is estimated at half a percent average for every hour the Switch is on, but this should go down as the cap charges so a fully charged dongle will likely pull much less than that. I'll put real world numbers here once testing is done.
Project milestones are as follows:
1) Make schematic/design board with Eagle and Fusion360 DONE.
2) Order parts and PCB's DONE.
3) Model enclosure to have exact dimensions and features of Switch game cart DONE.
4) Soldering, programming and testing of board - Waiting on parts.
5) Print the case on my FDM 3D printer. PETG for board enclosure, FLEX for cap/RCM jig. DONE. Went SLA for the prototype. Prints in the mail!
6) Tweaking. Add cool factor. DONE! I'll let you decide if it looks
cool enough.
7) Assembly and testing.
This project is licensed under the Creative Commons Attribution-ShareAlike 4.0 licence. Once I have a working prototype I'll share the Eagle files, gerbers, models and parts list. For those that aren't familiar, this means you can do pretty much anything you want with the designs as long as you link back to the original licence on my GitHub. If you're not comfortable soldering 0603 resistors by hand, assuming the testing goes well I'll be selling these on tindie for around $23 USD ($30 CAD). I'll also sell the populated PCB without the case if you want to print your own, as well as the RCM jig since it works best with the precision of an SLA or SLS printer and those aren't so common yet.
I had some fun and made up a sort of product poster you can find under the spoiler. It'll show you what it looks like and explain the more important details. I'll do up a second one closer to release with usage instructions and stuff. If people like the poster, I'm toying with the idea of getting some blank cartridge cases and making some nice "retail-looking" cases for them with similar fancy graphics. Leave a comment below if this is something you think you'd like to see, but it definitely won't be part of the first batch.
Thanks to everyone for all the support so far!
As ppl wil probably change payload from time to time still, there is no point of specific payload stickers IMO ;]
@
Psionic Roshambo:
