User Manual
Table Of Contents
- LRP76 Long Range Passive Reader/Writer
- Table of Contents
- Getting Started
- Mechanical Specifications
- Power and Electrical Interface
- Configuration Menu
- Standard RFID Interface
- 5.1 Introduction
- 5.2 Command Timeout Values
- 5.3 Address Blocks
- 5.4 ABx Error Codes
- 5.5 Command Descriptions
- 5.6 ABx Standard Commands
- 5.6.1 Command 4 (04 Hex): Tag Fill
- 5.6.2 Command 5 (05 Hex): Block Read
- 5.6.3 Command 6 (06 Hex): Block Write
- 5.6.4 Command 7 (07H): Read Tag Serial Number
- 5.6.5 Command 8 (08 Hex): Tag Search
- 5.6.6 Command D (0D Hex): Start/Stop Continuous Block Read
- 5.6.7 Command E (0EH) Read SN and Data
- 5.6.8 Command F (0FH) Start/Stop Continuous Read SN and Data
- 5.7 ABx Fast Commands
- 5.7.1 ABx Command Packet Structure
- 5.7.2 Command 4 (04 Hex): Tag Fill
- 5.7.3 Command 5 (05 Hex): Block Read
- 5.7.4 Command 6 (06 Hex): Block Write
- 5.7.5 Command 7 (07H): Read Tag Serial Number
- 5.7.6 Command 8 (08 Hex): Tag Search
- 5.7.7 Command D (0D Hex): Start/Stop Continuous Block Read
- 5.7.8 Command E (0EH) Read SN and Data
- 5.7.9 Command F (0FH) Start/Stop Continuous Read SN and Data
- Technical Specifications
- Models and Accessories
- ASCII Chart
Standard RFID Interface
18 LRP76 Long Range Passive Reader/Writer
For practical reasons (wakeup time, overhead) timeout values less
than 30 ms have negligible affects on LRP76 behavior. Therefore, the
examples given in this manual present the timeout range as 1EH to
FFFEH (30 to 65,534 ms).
Specifying a long timeout will not necessarily affect the time required
to complete a command, but merely instructs the LRP76 how long to
attempt the command before aborting. The timeout error is returned
only if the command can not be successfully executed. For example,
when the tag is not currently in the field.
Using a zero timeout value is not permitted and will return a syntax
error (21H).
NOTE:During write commands, the tag must remain in the field until
either the command completes successfully, or the timeout
period has expired. If a write command is initiated with a tag in
the antenna's active field and then the tag leaves the field
before the command has completed or times out, data may be
lost or corrupted. It is recommended that you use the longest
timeout value permitted by the application.
For applications where the tag positioning may not be controlled and
the tag movement cannot be limited to the antenna field, longer
timeouts and retries should be utilized in the application program. This
will ensure the highest success rates.
If an application demands the tag to travel at high speeds and retries
can not be utilized, it may be required to synchronize the tag travel
speed with the command timeouts. Use of a presence sensor may be
required to ensure that the LRP76 cannot timeout while the tag is
passing by. Many factors need to be considered for high speed
applications such as; address range, command type, tag and antenna
models, and the installation environment. Please contact Escort
Memory Systems' application support team for help with your
application.
5.3 Address Blocks
All read/write operations between the tag and the LRP76 are based
on 4-byte block transfers. Each operation, whether it invokes a single
data byte or 48 bytes, will read/write in multiples of four bytes.
This fact impacts timing issues in two cases:
• When the number of data bytes is not a multiple of 4.
• When the read or write does not start on one of the first block bytes
(0, 4, 8 and so on).