MagTek USB KB INTELLIHEAD - Manual (Page 46)

USB Keyboard Emulation Swipe Reader
38
SET KEYMAP ITEM COMMAND
Command number:
0x04
Description: This command is used to set a key map item of the active key map. The
active key map is determined by the active key map property. Data from a
magnetic stripe card is a sequence of ASCII characters. These ASCII
characters are mapped to key strokes and these key strokes are sent to the
host to represent the ASCII character. The key map maps a single ASCII
character to a single USB key usage ID and USB key modifier byte. The
key usage ID and the key modifier byte are transmitted to the host via
USB to represent the ASCII character. The ASCII value is the value of
the ASCII character to be transmitted to the host. See an ASCII table for
the values of the ASCII character set. The USB key usage ID is a unique
value assigned to every keyboard key. For a list of all key usage IDs see
Appendix A. The key modifier byte modifies the meaning of the key
usage ID. The modifier byte indicates if any combination of the right or
left Ctrl, Shift, Alt or GUI keys are pressed at the same time as the key
usage ID. For a list and description of the key modifier byte see
Appendix B. Once a key map item is modified, the changes take affect
immediately. However, the changes will be lost if the device is reset or
power cycled. To make the changes permanent, the save custom key map
command must be issued. To use the new custom key map after a reset or
power cycle, the active key map property must be set to custom.
Starting with the firmware release with software ID 21042812F01, when
both the key usage ID and the key modifier byte are set to 0xFF for a
given ASCII value, the ALT ASCII code is sent instead of the key map
values. The ALT ASCII code is a key press combination consisting of the
decimal value of the ASCII character combined with the ALT key
modifier. For example, to transmit the ASCII character ‘?’ (063 decimal),
keypad ‘0’ is sent combined with left ALT key modifier, next keypad ‘6’
is sent combined with the left ALT key modifier, last keypad ‘3’ is sent
combined with the left ALT key modifier.