User's Manual

30
Chapter 5 Communication Frame
5-1 Overview of Communication Frame
Ter mi -
nator
Page Specification
Header field Data field
＠
ADR A/H
Commu-
nication
Mode
Status
Command CR
(Parameter)
·············
6 1 3 2
1 1
The frame format is comprised of the header field of 3 bytes starting by @, the data field represented by ASCII
characters and the terminator <CR> (ASCII code (0D) h).
Name
Frame
length
(Byte)
Description Page
@ (1)
Start of communication
(40) h
ADR (1)
Reader No.
Hexadecimal notation O - F expressed in ASCII.
Header field
Status (1)
Controls, by a flag, the communication status
between the host and RF interface described in
4-6.
Fixed header
field, 3 bytes
4-6
Command (2)
Indicates an operation instruction to the host or RF interface
(4-5).
The communication control command does not execute RF
interface communications.
A header of 4 bytes as given below is further added to the RF
interface communication control command.
4-5
A/H (1)
Specify the format of data to be written on the tag.
Specify ’2’ for hex format and’3’ for ASCII format.
Communication Mode (1) Select the form of the RF interface communications (4-4). 4-4
Data field
Page Specification (6) Specify pages for communication with the tag (4-3). 4-3