User's Manual

ManualsBrandsOmron Corporation, RFID Business Development Department ManualsElectronicsRF ID Reader

5-3 Command-Response Format

5-3

5-19

5-3-1 Command Frame Structure

The Reader/Writer continuously receives signals from STX through ETX, and executes the command

when the correct node number is received (*1). If, after receiving an STX signal, another STX signal is

received before an ETX signal is received, the second STX signal is given command priority.

Node No. Command Code Option BCC

STX "" "" ETX

1 2 2 1 1

Name Description

STX

Indicates the beginning of a communication frame (text). Expressed by

ASCII code 02h.

Node No.

Indicates the Reader/Writer to communicate with by its node No. This

number can be set within the range between 00 and 31 decimal.(*1)

Command Code

Indicates the command that the Reader/Writer executes. For the

command codes that are available, refer to Command Code List in 5-3-

Option

Makes specified optional settings or specifies read/write data. For

details, refer to the format of the appropriate command.

ETX

Indicates the end of a communication frame (text) Expressed by ASCII

code 03h.

BCC

Stands for Block Check Character (hereinafter referred to as "BCC").

The result of the horizontal parity calculation from immediately after

STX through ETX is expressed using one character. You can enable or

disable the BCC command using the communications port setting

command.For BCC calculation method, refer to 5-3-8 Example BCC

Calculation.

：COM2 is a port for setup and can communicate without depending on a node No.

5-3-2 Response Frame Structure

Node No. Retry Flag Command Code Response code Text data BCC

STX "" "" "" "" ETX

1 2 1 2 2 1 1

Name

Description

Node No. Indicates the node No. that has been assigned to the Reader/Writer.

Retry Flag

This flag will be set to "0" when ACK/NACK control has been disabled.

In ACK/NACK control, a response will be re-transmitted with the

retry flag set to "1" if, after returning a response, ACK has not been

received within a pre-determined period of time or if NACK has been

received.

Command code Indicates the code of the command that the Reader/Writer executed.

Response Code

Indicates the result of command execution.

Refer to 5-3-7 Response Code List for different response codes.

Text data

Sent in response to specific commands. For the content, refer to the

frame structure of each command.

：The contents of STX, ETX, and BCC are the same as those in command frames.