The codes for the various digit keys and SYMBOL SHIFT can now be found.

		SUB	+10	Reduce the range to give +20 to
				+29.
		CP	+22	Separate the '@' character
		JR	Z,03B2,K-@-CHAR	from the others.
		CP	+20	The '-' character has also to be
				separated.
		RET	NZ	Return now with the 'final
				codes' +21, +23 to +29.
		LD	A,+5F	Give the '-' character a
		RET		code of +5F.
03B2	K-@-CHAR	LD	A,+40	Give the '@' character a code
		RET		of +40.