3 The [[http://ergodox.org][Ergodox]] keyboard is an absolutely fantastic design; I use it every
4 day at my office. However, I like to work from coffee shops and other
5 locations frequently, and I thought I might try my hand at designing
6 something a little more portable. The great thing about assembling
7 my Ergodox is that it taught be there's really nothing magical about
8 it; it's just a piece of circuitry with a bunch of switches read by a
9 microcontroller that speaks the USB HID interface.
11 The Atreus is meant to be complementary to the Ergodox as something
12 smaller, cheaper, and more travel-friendly. The case measures 25x11cm
13 and lacks even a number row, relying heavily upon the fn key. There is
14 no PCB in this design, requiring [[http://deskthority.net/workshop-f7/brownfox-step-by-step-t6050.html][a manual matrix wiring approach]].
15 However, given that there are only 4 rows and 10 columns, this isn't
16 as daunting as it could be.
20 See [[file:layout.txt][layout.txt]] for the key positions. Only a handful of punctuation
21 marks (and no digits) available unshifted, and all the modifiers are
24 I type in Dvorak but prefer to do the remapping in software rather than
25 hardware so I don't have to change layouts when I switch to my
26 laptop's internal keyboard.
32 I strongly prefer the feel and sound of [[http://www.digikey.com/product-detail/en/MX1A-E1NW/CH197-ND/20180][Cherry MX blue]] switches for typing.
34 However, I like having linear switches on the modifier keys (ctrl,
35 alt, super, shift, and fn). [[http://www.wasdkeyboards.com/index.php/products/keyboard-parts/cherry-mx-red-keyswitch-mx1a-l1nn-linear.html][Cherry MX red switches]] are nice and light
36 but are difficult to find. Cherry black switches are cheaper and
37 easier to source, but may be too heavy, especially for keys under
40 This layout has five modifiers and 35 non-modifiers.
44 In order to avoid ghosting, each switch needs a [[http://www.digikey.com/product-detail/en/1N4148TR/1N4148FSTR-ND/458811][diode]].
48 I'll be using a Teensy 3 since I have one on hand, but an [[https://www.adafruit.com/products/1315][Arduino
49 Micro]] or [[http://www.pjrc.com/teensy/index.html][Teensy 2]] would work too.
53 This [[http://keyshop.pimpmykeyboard.com/product/dsa-pbt-blank-sets][DSA-shaped base set]] has 52 1x keys plus a few extras we won't use.
57 Layered laser-cut acrylic; see [[file:case.svg][case.svg]]. 2mm for the bottom layer, 6mm for the others.
68 - Base keycap set: $18.00
71 =(+ 35 10 (* 40 0.052) 18 16)= -> $81.08 plus shipping and acrylic
73 - Digikey shipping: $5.32 in the US
74 - WASD (red switches) shipping: ??
75 - Signature Plastics shipping: ??
76 - Acrylic materials: ??
77 - Acrylic laser cutting: ??
81 Copyright © 2014 Phil Hagelberg
83 Released under the [[http://www.ohwr.org/projects/cernohl/wiki][CERN Open Hardware License 1.2]]