Project.... 3D printer Bluetooth USB serial terminal adapter


Hey everyone,

I made a 3D printer Bluetooth USB serial terminal adapter using a Teensy 4.0 as a USB host and a nRF52840 for the Bluetooth radio. It works well except when running a M503 command. I haven't been able to work out the buffer on the nRF52840 to get more than 1024 bytes though.

The complete project is on Thingiverse. There is also a short video on Youtube showing it in operation.

If anyone has criticism or input to improve the code - it's always appreciated.
Looks like a fun project.

Right now my 3d printer is dead and my two KickStarter dontations aappear like they may never ship.

Probably should just try to fix my Printerbot... Just the USB connector broke off it.
The wiring is kind of rough. I was trying to make the adapter small, but it makes it tedious to do the wiring. If it helps you, or anyone, I'm picky enough that I actually measured the wires. Lol. It would be really easy to wire it without the enclosure.

The wires are 26 ga. w\ silicone insulation. The red power wires are 40, 50 & 60mm, the black ground wires are 40 & (2) 60mm, the USB data lines are (2) 50mm and the serial lines are (2) 40mm.
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Nice project, but other than size, and power usage what's the bonus over using octo pi on a raspberry pi?
Imo, it's just cheaper if you only want a simple way to control the printer. I only use Marlin. I was trying to find a different route other than an esp32.
Yes, there is a way for your non-Bluetooth printer to become a Bluetooth label printer. Simply look for a USB Bluetooth Printer Adapter in electronic stores. It can cost up to $20. The adapter can be designed to be plugged into the printer's USB Type-A port.