User Guide

Table Of Contents
Allegro/Title-21 Tag Commands
71
Read Request (28h; C003h)
The Read Request command reads data from the specified area of the specified tag. This
command contains the following request fields:
Read Request Fields
Examples
An example command format is:
Field Value Description
TM OpCode 0x28 TM OpCode for tag modification operations
Timeout [2 bytes] Indicates how long the command should spend
attempting the operation, in milliseconds.
TM Options 0x00 Reserved for Future Use.
Transaction Type Code 0xC003 Allegro/Title-21 code indicating operation to per-
form.
Options [1 byte] Command specific options.
• Determines whether the AntiPlayBack/BIST
data will be included in the response.
Start Page Number [2 bytes] Indicates which page of the tag is to be read.
Page Count [1 byte] Number of pages to read.
Tag ID [4 bytes] Optional, based on value of Options parameter.
Indicates the ID of the tag to operate on.
User Password/
Global Password
[4/8 bytes] Optional, based on the value of the Options param-
eter. The password to operation on the tag, if
required.
FF 0C 28 ?? ?? 00 C0 03 ?? ?? ?? ?? ?? ?? ?? ?? ?? ??
SOH Length TM
OpCode
Timeout
(ms)
TM
Option
Transaction
Type Code
Option Page
Number
Page
Count
Tag ID CRC