Tal or Uxntal is a stack-based assembly language designed for the Uxn virtual machine. There are 256 instructions designed to work within a 16-bit addressing space.

@fib ( num* -- numfib* )
	#0001 GTH2k ?{
		POP2 JMP2r }
	SUB2k fib STH2 INC2
	SUB2 fib STH2r
		ADD2
JMP2r

The Uxn specification provides Tal with two 256 bytes circular stacks and 64kb of RAM. The language features support for anonymous functions, and arity checking.

FizzBuzz Implementation

@on-reset ( -> )
	#6400
	&loop ( -- )
		DUP <print-dec>
		#2018 DEO
		DUP #03 DIVk MUL SUB ?{ ;dict/fizz <print-str>/ }
		DUP #05 DIVk MUL SUB ?{ ;dict/buzz <print-str>/ }
		#0a18 DEO
		INC GTHk ?&loop
	POP2
	( exit ) #800f DEO
	BRK

@<print-dec> ( num -- )
	( x0 ) DUP #0a DIV <print-num>
	( 0x ) #0a DIVk MUL SUB
	( >> )

@<print-num> ( num -- )
	#30 ADD #18 DEO
	JMP2r

@<print-str> ( addr* -- )
	LDAk #18 DEO
	INC2 & LDAk ?<print-str>
	POP2 JMP2r

@dict ( strings )
	&fizz "Fizz $1
	&buzz "Buzz $1

Uxn

Uxn is a small stack-based computer with an implementation-first design. It is specialized for building small, low-energy, audio-visual applications. The specification for Uxn fits onto a single page, and its implementation is 100 lines of C. Finally, it powers the personal computing stack called Varvara.