When specifying the location of the Braille input keys on the standard computer keyboard, you must specify 8 dot definitions, in order, corresponding to dots 1, 2, 3, 4, 5, 6, 7, 8, respectively. For example, the default location is "FDSJKLA;": Braille dot 1 is represented by QWERTY letter "F", dot 2 by letter "D", dot 3 by letter "S", dot 4 by letter "J", dot 5 by letter "K", dot 6 by letter "L", dot 7 by letter "A", and dot 8 by the semicolon key.

The default location does not need to be specified, you can enable it by simply enabling the B option in the driver configuration string without specifying a dot pattern. We do specify it in WTC's shipped settings, however, because doing so clarifies the default behaviour and it is easier to make changes. Its definition, "FDSJKLA<59>", illustrates some important points:

Exactly 8 dots are defined
The letters are in uppercase
The semicolon for dot 8 is specified by embedding its ASCII value

The semicolon needs to be embedded because otherwise it would be interpreted as a substring separator in the driver configuration and the Braille keyboard setup would be terminated prematurely.

You can embed all characters if you wish, but providing the required dots can be represented by a character and you specify it in uppercase where there is a case distinction, there is no need to use character embedding except in one other case, the comma. You can specify certain options relating to the Braille input keyboard as part of the setup, as described elsewhere in this documentation. Options are specified as a string of characters immediately following the "B" directive and separated from the dot definitions by a comma. For this reason, if no options are specified and there is a comma in the dot definitions, the comma must be embedded as "<44>", or the characters preceding it will be interpreted as option settings. An alternative is to follow the "B" immediately by a comma without intervening option letters, then the dot definitions may include a comma literally.

However, not all keys can be represented in this way, even character keys. To illustrate this problem, consider a seemingly straightforward alternative Braille input configuration. The default Braille keyboard location occupies the "home position" on the QWERTY keyboard, which is generally the most convenient arrangement of the Braille dots for the user, but not always, a common preference is the bottom row, using the characters

"VCXM,.Z/"

corresponding to dots 12345678. Attempting to specify this location with

"VCXM<44>.Z/"

(note the comma embedding) will not work, because the characters fullstop and oblique stroke cannot be represented as characters in this context. Instead, you need to specify their "virtual key codes", and the correct dots definition for this alternative positioning of the Braille keys is

"VCXM<44>:BEZ:BF".

The virtual key code can be obtained using the keyboard information utility provide in WTC, on the directory dialling/setup menu. To use virtual key codes in Braille dot definitions, you must quote their hexadecimal representation, exactly 2 symbols, preceded by a colon ":". The colon character indicates to WTC that the next two characters represent the hexadecimal value of the virtual key code for the next Braille dot. There is no conflicting usage here, because the colon cannot represent a dot in character notation. Using virtual key codes for character keys is perfectly acceptable, just not necessary.

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Defining the Dot Positions