8.7.11 Command Identifier 0X53: Bulk Read - Balluff BIS U-4A7-082-01C-07-S4 Betriebsanleitung

BIS U-4A7-082- _1C-07-S4
Industrial RFID system - Read/write head
8
System integration (continued)

8.7.11 Command identifier 0x53: Bulk Read

Read user data from several data carriers located in the
detection range of the antenna. Via the data carrier
selection, all data carriers in the detection range can be
read out or only a subset previously selected with the
Select command.
The memory area to be read is defined via start address
and number of bytes.
Initially, the command reports only the number of data
carriers that have been detected. The requested data is
then read out and transmitted to the controller.
If detected data carriers are removed from the detection
range of the antenna before they are read out or if they
cannot be read out successfully, the data are marked as
invalid by a check byte.
Command:
Subaddress Meaning
0x00 1st bit string
0x01 Command
recognition
0x02 Start
address
(Low Byte)
0x03 Start
address
(High Byte)
0x04 Number of
bytes
(Low Byte)
0x05 Number of
bytes
(High Byte)
0x06 Data carrier
selection
0x07 Max. Tags
... None
0x1F 2nd bit
string
If execution is successful, the response is passed to the
input buffer in the following format:
Response:
Subaddress Meaning
0x00 1st bit string
0x01 Number of
tags
0x02 Number of
bytes (Low
Byte)
0x03 Number of
bytes (High
Byte)
54 english
Functional description
0x53: Bulk Read.
Start address from which
to read.
Start address from which
to read.
Number of bytes to be
read from start address.
Number of bytes to be
read from start address.
All = 0/Selected = 1
Maximum number of tags.
No meaning
If the 1st and 2nd bit
strings match, valid data is
present.
Functional description
Number of tags found
Bytes transferred per tag.
Bytes transferred per tag.
Subaddress Meaning
0x04 Data 1 [0]
... Data 1 [1]
... Data 1 [...]
... Check byte 1 In the last byte of the
... Data 2 [0]
... Data 2 [1]
... Data 2 [...]
... Check byte 2 In the last byte of the
... ...
... Data n [0]
... Data n [1]
... Data n [...]
... Check byte n In the last byte of the
0x1F 2nd bit string If the 1st and 2nd bit
Functional description
Transmission of the
1st byte read from the
1st data carrier.
Transmission of the 2nd
byte read from the 1st
data carrier.
Further data of the
1st data carrier.
1st data carrier, a check
byte is transmitted which
indicates whether the read
data are valid:
0x00: Data valid
0xFF: Data invalid
Transmission of the
1st byte read from the
2nd data carrier.
Transmission of the
2nd byte read from the
2nd data carrier.
Further data of the
2nd data carrier.
2nd data carrier, a check
byte is transmitted which
indicates whether the read
data are valid:
0x00: Data valid
0xFF: Data invalid
...
Transmission of the
1st byte read from the
nth data carrier.
Transmission of the
2nd byte read from the
nth data carrier.
Other data of the nth data
carrier.
nth data carrier, a check
byte is transmitted which
indicates whether the read
data are valid:
0x00: Data valid
0xFF: Data invalid
strings match, valid data is
present.