Write-in votes may be cast on voting equipment for any person whose name does not appear on the ballot as a candidate for the office being voted, subject to this section and the provisions of § 24.2-644 not in conflict with this section. Each write-in vote shall be entered in the receptacle or area designated on the machine for the office being elected. A write-in vote shall be cast in its appropriate place, in accordance with the instructions for that equipment, or it shall be void and not counted. Except on machines that provide a means to enter a name electronically, each write-in vote shall be entered by the voter in his own handwriting or hand printing.