I'm Tomu a tiny ARM microprocessor which fits in your USB port. I have two buttons and two LEDs.
We're available on mailing lists and IRC:
- IRC Channel - irc://irc.freenode.net/#tomu - IRC channel for discussing anything related to the project.
- Announcement mailing list - Low traffic list for announcements.
- Discussion mailing list - List for discussing development / new features / etc.
Built out of a 3d printed part + 2 layer "thin" PCB. LCA2018 and Crowd Supply boards are 0.6mm.
The board requirements are very lo-fi:
- 6mil traces
- 6mil clearance
- 0.3mm drill / 0.6mm vias
The important features are:
- Available on Digikey
- QFN24 - 5mm x 5mm package
- Inbuilt 5V to 3V3 regulator.
- Crystal-less USB
These make something which is almost hand solder-able fit into the tiny size.
All parts are available from Digikey, and are readily available from other suppliers.
- 2 x 0402 - 15 Ohm - Digikey
- 2 x 0402 - ~50 Ohm (Depends on LED choice)
- Capacitors - Digikey Capacitors 0402, >1uF
- 2 x Capacitor 1uF 0402
- 1 x Capacitor >10uF 0402
- 2 x LED 0402
- You choice of two different colors (might require adjustment of R1/R2).
- 5mA LEDs are better choice.
- Get highest millicandela rating you can.
- Digikey Search of LEDs in 0402 package
- 1 x EFM32HG309 or EMF32HG308
The PCB is slightly narrower than a USB slot, and is significantly flatter. Tomu is designed to be sandwiched in the USB port alongside a case of some sort. Early prototypes used a business card that had been folded over, however the crowd funding campaign made enough to cut steel and make a case.
Designs are available in the "case/" directory. Cases for earlier versions tend to require higher tolerance on 3D printers.
The aim was to prove that a device which fits in your USB port could be created by hobbists in small quantities extremely cheaply.
TOMU comes from the abbreviation "Tim's Open Micro USB".
What ever you want! If you do create something, please send me the info!
The contents of this repository excluding
third_party folderis released under your choice of the following two licences:
- the "Creative Commons Attribution-ShareAlike 4.0 International License" (CC BY-SA 4.0) full text of this license is included in theLICENSE.CC-BY-SA-4.0 file and a copy can also be found at http://creativecommons.org/licenses/by-sa/4.0/
- the "TAPR Open Hardware License" full text of this license is included in the LICENSE.TAPR file and a copy can also be found athttp://www.tapr.org/OHL