Chapter 5 Using Overlay Keyboards

5.2 Choosing an Overlay Keyboard

Different keyboards are available in different sizes and with different features. Most keyboards need special software in which case you cannot consider the keyboard without also considering its accompanying software and the curriculum software that it needs to access. Software is discussed later on; we’ll look at the ‘basics’ of the keyboards first.

Size

The size of the keyboard and overlay area is important:

Larger keyboards (e.g. A3 size) are useful for:

•group work where several children can use it at once;

•designing overlays with lots of keys, showing larger pictures and text;

•use by children who have difficulty targeting small keys.

The smaller keyboards may be more suitable for young children and those who have limited range of movement.

The British-made Concept Keyboards take A3 or A4 size overlays which are convenient for making up overlays since paper is readily available. The North American devices have different overlay sizes so you have to buy special paper from the keyboard suppliers or cut the overlay to shape.

Number of Individual Keys

The keys on most of the keyboards are approximately 1 or 2 cm square. This means the overlay picture areas are big and ‘blocky’ – fine for letters and word banks but not so good for detailed pictures or maps. Informax has 4096 individual keys so that very fine detailed overlays can be designed.

Computers, Connections & Keyguards

Different keyboards work with different computers and need different plugs and leads. These are described in more detail later. Keyguards are helpful for children who press keys by mistake (see Chapter 3 Accessing the Keyboard for more information about keyguards).

Cost

The prices given in the Table 5-1 are for the keyboard only. The Concept keyboards need software as well (see Table 5-2 for driver software prices).

Overlay Keyboards

‘Concept’ Keyboards

•‘Old blue’ Concept Keyboard

These keyboards were originally designed for the BBC micro in the early 1980s, and are still commonly used in schools. They have a flat ribbon cable which plugs into the User or Parallel port on BBCs. They can also be plugged into RM Nimbus 186, RM 386 ‘M’ series and Acorn machines fitted with optional User Ports. The keyboards were available in A4 or A3 sizes with 128 keys. A large amount of good educational software was written for the Concept Keyboard, and much of it is still in use. The Concept Keyboards can also operate the more recent software written for Concept Universal boards.

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