LD	(HL),A	Store the byte.
		INC	HL	Point to the fifth location.
		LD	(HL),+00	The fifth byte is set to zero.
		POP	HL	Return with HL pointing to the
		RET	first byte on n on the stack

THE 'FLOATING-POINT TO BC' SUBROUTINE
This subroutine is called from four different places for various purposes and is used to compress the floating-point 'last value' into the BC register pair. If the result is too large, i.e. greater than 65536 decimal, then the subroutine returns with the carry flag set. If the 'last value' is negative then the zero flag is reset. The low byte of the result is also copied to the A register.
2DA2	FP-TO-BC	RST	0028,FP-CALC	Use the calculator to make HL
		DEFB	+38,end-calc	point to STKEND-5
		LD	A,(HL)	Collect the exponent byte of
		AND 	A	the 'last value'; jump if it is
		JR	Z,2DAD,FP-DELETE zero, indicating a 'small integer'.
		RST	0028,FP-CALC	Now use the calculator to round
		DEFB	+A2,stk-half	the 'last value' to the nearest
		DEFB	+0F,addition	integer, which also changes it to
		DEFB	+27,int	'small integer' form on the
		DEFB	+38,end-calc	calculator stack if that is pos-
				sible, i.e. if -65535.5 <=
				x <65535.3
2DAD	FP-DELETE	RST	0028,FP-CALC	Use the calculator to delete the
		DEFB	+92,delete	integer from the stack; DE still
		DEFB	+38,end-calc	points to iit in memory (at
				STKEND).
		PUSH	HL	Save both stack pointers.
		PUSH	DE	
		EX	DE,HL	HL now points to the number.
		LD	B,(HL)	Copy the first byte to B.
		CALL	2D7F,INT-FETCH	Copy bytes 2, 3 and 4 to C, E
				and D.
		XOR	A	Clear the A register.
		SUB	B	This sets the carry unless B is
				zero.
		BIT	7,C	This sets the zero flag if the
				number is positive (NZ denotes
				negative).
		LD	B,D	Copy the high byte to B.
		LD	C,E	And the low byte to C.
		LD	A,E	Copy the low byte to A too.
		POP	DE	Restore the stack pointers.
		POP	HL
		RET		Finished.

THE 'LOG (2^A)' SUBROUTINE
This subroutine is called by the 'PRINT-FP' subroutine to calculate the approximate number of digits before the decimal in x, the number to be printed, or, if there are no digits before the decimal, then the approximate number of leading zeros after the decimal. It is entered with the A register containing e', the true exponent of x, or e'-2, and calculates z=log to the base 10 of (2^A). It then sets A equal to ABS INT (Z + 0.5), as required, using FP-TO-A for this purpose.
2DC1	LOG (2^A)	LD	D,A	The integer A is stacked, either
		RLA		as 00 00 A 00 00 (for positive
		SBC	A,A	A) or as 00 FF A FF 00 (for 
				negative A).
		LD	E,A	These bytes are first loaded into
		LD	C,A	A, E, D, C, B and then STK-
		XOR	A	STORE is called to put the
		LD	B,A	number on the calculator stack.