Counting graphic keys

In an attempt to rationalize many different keyboard layouts, the ISO/IEC 9995 international standard specifies the layout of a harmonized keyboard that has 48 graphic keys and the space bar in the alphanumeric zone.

Guideline E1

Create a keyboard with at least 48 graphic keys and the SPACE key to support entry of Latin based characters.

Although the keyboard for the USA can contain only 47 graphic keys, almost all manufacturers produce a 48-key keyboard to avoid the added costs of designing new keyboard layouts for other countries. For a product to avoid being unduly restricted, the logic that deals with keyboard direct output must be compatible with keyboard layouts having at least 48 graphic keys. You can design a product to use one or more keyboards.