USB type-A dongle based on the nRF52840 microcontroller. Meant to run the COB firmware.
| Filename | Latest commit message | Latest commit date |
|---|---|---|
| 1_Library.pretty | ||
| .gitignore | ||
| fp-info-cache | ||
| fp-lib-table | ||
| LEARNING.md | ||
| LICENSE | ||
| output.kicad_jobset | ||
| README.md | ||
| rf-dongle-jig.jpg | ||
| rf-dongle.jpg | ||
| rf-dongle.kicad_pcb | ||
| rf-dongle.kicad_prl | ||
| rf-dongle.kicad_pro | ||
| rf-dongle.kicad_sch | ||
RF Dongle
USB type-A dongle based on the nRF52840 microcontroller.
This dongle is meant to run the COB firmware, though technically you can flash whatever you want on it.
Current state
What works
- The dongle can be programmed through the SWD pads exposed on the back of the PCB.
- Debugging the microcontroller while it runs also works, through the same SWD pads.
- LEDs and reset buttons work.
- The chip antenna works and has a good range. I haven't tested its limit, but I tried both sending and receiving packets across a room (5-ish meters with a wall in between) and it worked fine and that's more than enough for my application.
- USB power is working, the device gets detected by the host, and it can enumerate as a HID device (haven't tried other USB 2.0 classes, but they should in theory work).
What needs improvement
- The USB connector (PCB trace) is quite thin, and in some USB ports it doesn't make a solid connection. One workaround is to add some tape on the underside of the PCB to increase its thickness. Need to figure out a neater solution though.
Pics
This is the manufactured PCB (at this commit). The component pads are designed to make it easier to hand solder the components, which is what I did.
Below is the test jig I'm using to program and debug the dongle. I hacked this together with a perforated board, a few pogo pins, and battery connectors I had lying around.
Contributing
If you (unlike me) know what you're doing, and have tips for my circuit design, please create an issue and tell me about it 🙏
Learning
If you're curious about my learning journey with this project, I've documented that here.