Karasu 14-key combination-stroke keyboards
ASCII rendering of table version on
http://fu.cd5k.net/vrs/kbd/
By Bytemoth - CC BY-SA 4.0

Layout:
[ ] [C] [I] [2] [bksp] [ALTE]
[/n] [M] [V] [X] [shf] [MATH]
[ ] [ spacebar ] [tab] [CAPS]

Keys:
/n - Return/Enter
C - +100 (Navigation Lock)
I - +1
2 - +2
bksp - Backspace
ALTE - Alternate character set lock
M - +1000 (Menu/Escape)
V - +4
X - +10
shf - Shifted character set toggle
MATH - Mathematics character set lock
CAPS - Shifted character set lock

Keypress chart (explained below):
keys  1 2 4 A 3 5 B 6 C E 7 D F G H    CAPS  1 2 4 A 3 5 B 6 C E 7 D F G H
-----------------------------------    -----------------------------------
ABCD  e t a o i n s h r d u c m w f    ABCD  E T A O I N S H R D U C M W F
ALTE  g y p ? b k [ j ] ` z ' , . _    ALTE  G Y P ! B K < J > ~ Z " ; : |
MATH  1 2 4 0 3 5 ( 6 ) / 7 + - * =    MATH        @   $ { ^ } % & #

1-H (17) are typed by simultaneously pressing the various combinations of I, 
II, V, and X (+1, +2, +4, and +10). The M key is Menu or Escape except in 
Navigation Lock, which is toggled with C. Navigation Lock converts the 
following keys: I/M/V/X to up/left/down/right, ALTE/MATH to PgUp/PgDn, 
Tab/CAPS to Home/End, II+Tab/II+CAPS to Start/EOF.