#include "rom.h"
#include "macros.h"
#include "globals.h"

	* = $300		; any address outside of page zero is okay because all code is relocatable

RCD(DEMO)

	CMN
	SET(R0, 9.4662)
	SET(R1, SQRT2)
	LDI(R7, R1)
	MUL(R7, R7, R7)
	PSH(R0)
	BRS(FACTORIAL)
	POP(R4)
	SET(R5, E)
	LDI(R6, R5)
	SET(R1, ZER)
	INR(R1)
	SVI(R1, R6)
	LDI(R0, R1)
	ESC
	BRK
	
BGN(FACTORIAL)

	POP(R1)
	SET(R2, 1)
	MOD(R3, R1, R2)
	SUB(R1, R1, R3)
_1	TST(R1)
	BRZ(_2)
	MUL(R2, R2, R1)
	DCR(R1)
	BRA(_1)
_2	PSH(R2)
	RTN
	
END(FACTORIAL)

END(DEMO)

RDT(_)

	; preset constants
	DEF(PI, 3.14159)
	DEF(E, 2.71828)
	DEF(SQRT2, 1.41421)

	; working space
	RES(2)

END(_)