User Manual

September 2001 S6350 Reader Reference Guide
28
Request Packet Format
Standard reader Request Packet Format (See Section 3.1)
ISO Command
Data
Header Packet
Length
Node
Address
Command
Flag
Command
Config.
Byte
Data
Checksum
‘01
hex
’ LSB MSB LSB MSB Flags ‘60
hex
’ XX
hex
Data Byte 1 Byte 2
Byte 0 bytes
1 - n
1 byte 2 bytes 2 bytes 1 byte 1 byte
1 byte n
bytes
2 bytes
Request Packet Description
Field Length Description
Header 1 byte Defines the start of the packet (01
hex
).
Packet Length 2 bytes Defines the length of the packet, including checksum.
Node Address 2 bytes Defines the Node address of the reader.
Command Flags 1 byte Defines how a command will be executed.
Command 1 byte Defines the command for the reader to execute (60
hex
for
ISO 15693-3 commands)
Data 0 - n
bytes
Defines the data required by the reader for a command.
Checksum 2 bytes Byte 1 is an XOR checksum of all elements from the
header to the last byte
Response Packet Format for ISO/IEC 15693-3
Similar to the request packet, the response packet consists of the header, packet length, node
address, command flags, reader command (60
hex
), ISO/IEC 15693-3 command/data bytes 0 to
some number “m” and the checksum.
The ISO Response Data packet can come in one of two possible generic formats: (a) One for
the ISO Inventory Response, and (b) all other ISO responses. These will be highlighted in the
following sections.
Note:
With the exception of the ISO Inventory Response packet, the format
for each standard response packet is the same.
The Error Byte (ISO Response Data Byte 0)
There are three possible reader errors that can be generated in response to an ISO 15693
command. This error code will be returned within the Error Byte (Byte 0) of the ISO
Response Data. The error codes are as follows:
01
hex
Transponder not found
02
hex
Command not supported
04
hex
Invalid flags