Reading Keyboard Input in 0x10c's DCPU-16 Assembly

The as of yet undocumented DAT op code can also be used to read keyboard input by simply referencing dat 0. Here's the code from Notch's pastebin:

; Reading characters from the keyboard

; by Markus Persson

#macro nextkey(target) {

 push(i)

 set i,[keypointer]

 add i,0x9000

 set target,[i]

 ife target,0

jmp end

 set [i],0

 add [keypointer], 1

 and [keypointer], 0xf

:end

 pop(i)

}

:keypointer

dat 0