User Manual

September 2001 S6350 Reader Reference Guide

3.1.2 Response Packet Format (Reader to Host)

Field Name SOF

Field Size 1 byte

Field Value 01

hex

Purpose Start of Frame

Field Name Length

Field Size 2 byte LSB first

Field Value Packet dependent

Purpose Describes the length of the whole packet including SOF

Field Name Node Address

Field Size 2 byte LSB first

Field Value 0000

hex

Purpose always 0000

hex

Field Name Command flags

Field Size 1 byte

Field Value Varies by command

Purpose Specifies the action just taken by the reader

Field Name Command

Field Size 1 byte

Field Value Varies by command

Purpose Specifies the action just taken by the reader

Field Name Data

Field Size 0 to 23 bytes

Field Value Command dependent

Purpose Contains the parameters and data for the command just processed

Field Name BCC

Field Size 2 bytes

Field Value 16 bit LRC of the preceding packet including the SOF

Purpose Allows the host to validate the correct reception of the response

packet

3.1.3 Command Flags Request

The command flags in the request packet control the actions of the reader. The meanings of the

bits are defined below.

Bits 0-3 Reserved for future use and should be set to ‘0’ for upward

compatibility.

Bit 4 Is the address flag and if set, the command is only performed on

transponders whose address matches the data section of the packet.

Bits 5-7 Reserved for future use and should be set to ‘0’ for upward

compatibility.