DTM434 DTM435
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9.2 Data transfer with an ID tag
9.2.1 Read UID of the ID tag
The UID (Unique Identification Number) of the ID tag is available in object 0x2180 as soon as an ID
tag is within the reading range of the device. If no ID tag is available, the value 0x0000000000000000
is entered.
If the object is mapped on a TPDO, transmission is event-controlled as soon as an ID tag enters the
reading range or is removed from the reading field.
For 32-bit controllers, the following objects are used instead of object 0x2180: 0x2190 and
0x2191.
9.2.2 Read data from the ID tag via PDO transfer
The transfer of the PDO data from the ID tag is event-controlled. That means that the configured
TPDOs are automatically transmitted by the device when the data change. This is the case, for
example, when a new ID tag is detected in the detection range of the device. The data is automatically
read by the ID tag and transferred by means of the TPDOs via the CAN bus.
The data that was read by the ID tag and assigned to a TPDO is in the objects 0x220A with the sub-
indices 0x01-0x40.
Only that data is read by the ID tag that is assigned to a TPDO. Data objects that are not
assigned are not updated automatically.
There are two objects for each data object that are used for configuration:
•
0x2200 (read start address),
•
0x2201 (read length) with sub-indices matching the data object.
The start address in the user data area of the ID tag and length of the files to be read are set in the
objects.
For 32-bit controllers, the object 0x220B must be used instead of object 0x220A. The maximum
data length is restricted to 32-bit data (4 bytes).
If the configured data length is smaller than the data length of the object used (64 bits or 32
bits), the remaining bits are filled with 0.
Max. 64 bits or 32 bits can be transmitted in one TPDO. For the transmission of larger amounts
of data, further TPDOs are assigned and the corresponding data objects are configured.
9.2.2.1 Example 1
The data range 0x10 to 0x18 (8 bytes) is to be transferred with the 2nd TPDO.
TPDO
Settings
for PDO
mapping:
COB
Object
directory:
Object
index
Object
directory:
Object
sub-
index
Object
directory:
Object
length
2
Node ID + 0x0280
0x220A
0x01
0x40
Object directory
Index
Sub-index
Name (object)
Value
0x2200
0x01
Read start of the address
(start of the address range on
the ID tag to be read)
0x10
0x2201
0x01
Read length (length of the
memory range on the ID tag
to be read; max. 8 bytes)
0x08
