User's Manual

COBALT UHF-SERIES CHAPTER 5: COMMAND PROTOCOLS
PAGE 52 OF 140
5.4.2 ABx Fast - Command Packet Structure
The packet structure of all ABx Fast RFID commands contains certain basic
elements, including Command Header, Command Size, Command ID and
Command Terminator. Packet element and parameter availability depends on the
command being performed.
COMMAND PACKET ELEMENT CONTENT SIZE
COMMAND HEADER
:
The first two bytes of an ABx Fast command.
0x02, 0x02 2 bytes
COMMAND SIZE
:
This two-byte integer defines the number of bytes in the
packet (excluding Header, Command Size, Checksum
and Terminator).
0x0007 +
(number of
bytes of
additional data)
2-byte integer
COMMAND ID:
This single-byte value indicates the RFID command to
execute.
0x06
(Write Data)
1 byte
START ADDRESS
:
This two-byte integer indicates the location of tag
memory where a read or write operation shall begin.
0x0000 2-byte integer
BLOCK SIZE
:
This two-byte integer represents the number of bytes
that are to be read from or written to the RFID tag.
0x0001 2-byte integer
TIMEOUT VALUE
:
This two-byte integer indicates the maximum length of
time for which the controller will attempt to complete the
command. Measured in milliseconds, this value can
have a range of 0x0001 to 0xFFFE or between 1 and
65,534 msecs.
0x07D0
(0x07D0 =
2000 x .001 =
2 seconds)
2-byte integer
ADDITIONAL DATA
:
This parameter uses one byte to hold a single character
for fill operations and supports the use of multiple bytes
when several characters are needed for write
commands (when applicable).
0x00 1 or more
bytes
CHECKSUM
:
This optional parameter holds a single-byte checksum
(only applicable when using ABx Fast with Checksum).
Optional 1 byte (when
applicable)
COMMAND TERMINATOR
:
The single-byte command packet terminator is always
0x03 for ABx Fast.
0x03 1 byte
Table 5-6: ABx Fast - Command Packet Structure