DEFB	+01,exchange	sa,sb,sa,sb
		DEFB	+31,duplicate	sa,sb,sa,sb,sb
		DEFB	+E0,get-mem-0	sa,sb,sa,sb,sb,sa
		DEFB	+A0,stk-zero	sa,sb,sa,sb,sb,sa,0
		DEFB	+C1,st-mem-1	(mem-1 is set to zero)
		DEFB	+02,delete	sa,sb,sa,sb,sb,sa
		DEFB	+38,end-calc

(Here sa denotes X+Z and sb denotes Y - Z*SIN (PI/A)).

		INC	(mem-2-1st)	Incrementing the exponent byte
				of mem-2 sets mem-2 to
				2*Z*SIN(PI/A).
		CALL	1E94,FIND-INT1	The last value X+Z is moved
		LD	L,A	from the stack to A and copied
				to L.
		PUSH 	HL	It is saved in HL.
		CALL	1E94,FIND-INT1	Y - Z*SIN (PI/A) goes from the
		POP	HL	stack to A and is copied to H.
		LD	H,A	HL now holds the initial point.
		LD	(COORDS),HL	It is copied to COORDS.
		POP	BC	The arc-count is restored.
		JP	2420,DRW-STEPS	The jump is made to DRAW.

(The stack now holds X+Z, Y - Z*SIN (PI/A), Y - Z*SIN (PI/A), X+Z).

THE DRAW COMMAND ROUTINE
This routine is entered with the co-ordinates od a point X0, Y0, say, in COORDS. If only two parameters X, Y are given with the DRAW command, it draws an approximation to a straight line from the point X0, Y0 to X0+X, Y0+Y. If a third parameter G is given, it draws an approximation to a circular arc from X0, Y0 to X0+X, Y0+Y turning anti-clockwise through an angle G radians.
     The routine has four parts:
  i. Just draws a line if only 2 parameters are given or if the diameter of the implied circle is less than 1;
 ii. Calls CD-PRMS1 at 247D-24B6 to set the first parameters;
iii. Sets up the remaining parameters, including the initial displacements for the first arc;
 iv. Enters the arc-drawing loop and draws the arc as a series of smaller arcs approximated by straight lines, calling the line-drawing subroutine at 24B7-24FA as necessary.
Two subroutines, CD-PRMS1 and DRAW-LINE, follow the main routine. The above 4 parts of the main routine will now be treated in turn.
i.   If there are only 2 paramaters, a jump is made to LINE-DRAW at 2477. A line is also drawn if the quantity Z=(ABS X + ABS Y)/ABS SIN(G/2) is less than 1.  Z lies between 1 and 1.5 times the diameter of the implied circle. In this section mem-0 is set to SIN (G/2), mem-1 to Y, and mem-5 to G.

2382	DRAW	RST	0018,GET-CHAR	Get the current characater.
		CP	+2C	If it is a comma,
		JR	Z,238D,DR-3-PRMS	then jump.
		CALL	1BEE,CHECK-END	Move on to next statement if
				checking syntax.
		JP	2477,LINE-DRAW	Jump to just draw the line.
238D	DR-3-PRMS	RST	0020,NEXT-CHAR	Get next character (the angle).
		CALL	1C82,EXPT-1NUM	Angle to calculator stack.
		CALL	1BEE,CHECK-END	Move on to next statement if
				checking syntax.
		RST	0028,FP-CALC	X, Y, G are on the stack.
		DEFB	+C5,st-mem-5	(G is copied to mem-5)
		DEFB	+A2,stk-half	X, Y, G, 0.5
		DEFB	+04,multiply	X, Y, G/2
		DEFB	+1F,sin	X, Y, SIN (G/2)
		DEFB	+31,duplicate	X, Y, SIN (G/2), SIN (G/2)