The Atreus is meant to be complementary to the Ergodox as something
smaller, cheaper, and more travel-friendly. The case measures 25x11cm
and lacks even a number row, relying heavily upon the fn key. There is
-no PCB in this design, requiring [[http://deskthority.net/workshop-f7/brownfox-step-by-step-t6050.html][a manual matrix wiring approach]].
+no PCB in this design, requiring [[http://wiki.geekhack.org/index.php?title=Hard-Wiring_How-To.html][a manual matrix wiring approach]].
However, given that there are only 4 rows and 11 columns, this isn't
as daunting as it could be. It also allows for quicker iteration on
design changes since alterations only require cutting a new case.
for non-modifier thumb keys.
**** Recommended switch types for bottom row
-- shift: red
-- super: red
-- tab: blue
-- bksp: green
-- ctrl: black
-- fn: black
-- space: green
-- alt: black
-- enter: blue
-- esc: blue
-- page up: blue
-- page down: blue
+
+- red: shift, super
+- black: fn, ctrl, alt
+- green: space, backspace, enter?
If you don't bother with the spring replacement step mentioned above,
use blues instead of greens and blacks instead of reds. Or just use
*** Microcontroller
-I'll be using a Teensy 3 since I have one on hand, but an [[https://www.adafruit.com/products/1315][Arduino
-Micro]] or [[http://www.pjrc.com/teensy/index.html][Teensy 2]] would work too.
+An [[https://www.adafruit.com/products/1315][Arduino Micro]] or [[http://www.pjrc.com/teensy/index.html][Teensy 2]] is recommended.
*** Keycaps
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.
+*** Screws
+
+Seven M3 machine screws hold the whole thing together. The length of
+the screws depends on the thickness of the materials you use for the
+case.
+
** Case
Layered laser-cut acrylic; see [[file:case.svg][case.svg]].
the spacer that goes under the fourth, which is the plate on which the
switches are mounted. These should be cut in 4.5mm.
+On a 100W Epilog laser, the 3mm layers cut in about a minute and a
+half. I did a run with 6mm acrylic of the other layers which took
+nearly 6 minutes, but with the recommended 4.5mm thickness it should
+be closer to four or five.
+
** Firmware
-TODO: Uhhh...
+My [[https://github.com/technomancy/tmk_keyboard/tree/atreus][fork of the tmk firmware]] has support for the Atreus
+layout. Currently only supports software-dvorak--the default layer is
+all qwerty, but the punctuation keys send keycodes assuming that the
+qwerty->dvorak transformation will be applied to them, so they don't
+make sense otherwise.
-** BOM
+** Recommended Bill of Materials
- 37 MX Blues @ $1.00
- 5 MX Blacks @ 0.80
- 42 diodes @ $0.052
- Base keycap set: $18.00
- Teensy 2: $16
-- Acrylic materials: $11 (cheaper if transparent acrylic is used)
-- Acrylic laser cutting: $18 at $3/min
+- Acrylic materials: $11
+- Acrylic laser cutting: 6 at $3/min (varies by thickness of acrylic)
+
+=(+ 37 (* 5 0.8) (* 42 0.052) 18 16 11 (* 3 6))= -> 106.18 plus tax/shipping
+
+- Digikey (switches and diodes) US shipping: $5.32
+- Signature Plastics (keycaps) shipping: $8.00
+- PJRC (teensy) shipping: $3.03
-=(+ 37 (* 5 0.8) (* 42 0.052) 18 16 11 18)= -> 106.18 plus shipping and cutting
+** Cost-saving Options
-- Digikey (switches and diodes) shipping: $5.32 in the US
-- Signature Plastics (keycaps) shipping: ??
+There are a few ways to get the cost under $100. Using all black
+switches brings the total to $98, but I strongly recommend against
+this unless you're already familiar with the feel of the various
+Cherry switches. Using wood for the case will reduce both the
+materials cost as well as the amount of time needed to cut the
+case. Replacing the colored acrylic with transparent might also save a
+few dollars.
** License