MagTek USB MagnePrint Swipe Reader with Encryption - Manual (Page 52)

USB MagnePrint Swipe Reader with Encryption
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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.
Data structure:
Request Data:
Offset Field Name Description
0 ASCII value Value of the ASCII character to be set in
the key map. This can be any value
between 0 and 127 (0x7F). For example,
to set the key map item for ASCII
character ‘?’ (card data end sentinel) use
the ASCII value of ‘?’ which is 63 (0x3F).
1 Key Usage ID The value of the USB key usage ID that is
to be mapped to the given ASCII value.
For example, for the United States
keyboard map, usage ID 56 (0x38)
(keyboard / and ?) is mapped to ASCII
character ‘?’. To change this to the ASCII
character ‘>‘ use usage ID 55 (0x37)
(keyboard . and >).