User's Guide

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13.3 Ethernet Transmission
A data transmission layer has been used for communication to our reader over Ethernet, just like in serial
communication.
The data transmission layer over Ethernet is a much more simple solution here since the TCP/IP protocol already has a
data security layer. As TCP/IP is a stream protocol, only the packet beginning and packet end are necessary.
There are 3 frame types in the protocol used in the Generation 3 readers.
If no data have been received for 100 milliseconds within a frame, the received part frame is dismissed. The payload (D1
to Dn) is identical to the Generation 2 payload.
13.3.1 Ethernet Transmission Generation 2 Readers
Frame Set-up
A frame looks as follows:
Start + data block + end
The start is made up of
0xAA 0xBB 0x01 0x01
, whereby the rst 1 is the Datetransmit byte and the second 1 is a Stu-
byte. The end is made up of
0xAA 0xCC
. If the byte
0xAA
appears in the KBRP frame, it must be doubled (
0XAA
0xAA
0xAA
).
Port
The TCP communication port is the port 4007.
Example
The frame
ASyncGetEPCs
is shown here as an example. The ID for this command is
0x0111
, which makes the frame
look as follows:
0xAA 0xBB 0x01 0x01 0x11 0x01 0xAA 0xCC
Extended Block Structure
If a data block to be transmitted exceeds 16kB, it is necessary to subdivide into several 16-kB blocks. These blocks
receive a block number, and the rst block contains the total data length. It is necessary to conrm the reception of
each block by means of an answer.
First block:
Start + block number always 0 + 4-byte total data length + data block + end
All other blocks:
Start + block number + data block + end
Answer to conrm the reception:
Start + block number + end
The start consists of
0xAA 0xBB 0x0E 0x01
. The end consists of
0xAA 0xCC
. If the
0xAA
occurs in the KBRP frame, it is
necessary to double it:
0xAA
0xAA 0xAA
.