Command number, Data length, Data – MagTek USB KB INTELLIHEAD User Manual
Page 22: Result code

USB Keyboard Emulation Swipe Reader
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COMMAND NUMBER
This one-byte field contains the value of the requested command number. The following table
lists all the existing commands.
Value
(Hex)
Command Number
Description
00
GET PROPERTY
Gets a property from the device
01
SET PROPERTY
Sets a property in the device
02
RESET DEVICE
Resets the device
03
GET KEYMAP ITEM
Gets a key map item
04
SET KEYMAP ITEM
Sets a key map item
05
SAVE CUSTOM KEYMAP
Saves the custom key map
DATA LENGTH
This one-byte field contains the length of the valid data contained in the Data field.
DATA
This multi-byte field contains command data if any. Note that the length of this field is fixed at
22 bytes. Valid data should be placed in the field starting at offset 2. Any remaining data after
the valid data should be set to zero. This entire field must always be set even if there is no valid
data. The HID specification requires that Reports be fixed in length. Command data may vary
in length. Therefore, the Report should be filled with zeros after the valid data.
RESULT CODE
This one-byte field contains the value of the result code. There are two types of result codes:
generic result codes and command-specific result codes. Generic result codes always have the
most significant bit set to zero. Generic result codes have the same meaning for all commands
and can be used by any command. Command-specific result codes always have the most
significant bit set to one. Command-specific result codes are defined by the command that uses
them. The same code can have different meanings for different commands. Command-specific
result codes are defined in the documentation for the command that uses them. Generic result
codes are defined in the following table.
Value
(Hex)
Result Code
Description
00
SUCCESS
The command completed successfully.
01
FAILURE
The command failed.
02
BAD PARAMETER
The command failed due to a bad
parameter or command syntax error.