Balluff BDG F-NH Series, Configuration Manual

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Triggered by a manufacturer specific event (change of position value):
To use this transmission type, sub-index 2 has to be FEh and the event timer in sub-index 5 has to be disabled
(00h), e.g.:
600h+ID 8 2Fh 00h 18h 02h FEh 00h 00h 00h
CAN-ID DLC Command Object L Object H Sub-
Index
Byte0 Byte1 Byte2 Byte3
Table 8.52: Parametrization of PDO1 Sub-Index 2
600h+ID 8 2Bh 00h 18h 05h 00h 00h 00h 00h
CAN-ID DLC Command Object L Object H Sub-
Index
Byte0 Byte1 Byte2 Byte3
Table 8.53: Parametrization of PDO1 Sub-Index 5
After resetting, the encoder’s PDO1 will be in asynchronous mode and be sent out if the measuring value
changes.
•
The use of this setting may cause heavy bus load. Therefor we recommend the
use of synchronous or timer triggered transmission.
8.5.4 Variable PDO-mapping
Variable PDO-mapping means that the PDO payload can be configured by the user. This mapping must match
between encoder and receiver. The maximum payload for a PDO is 8 bytes. The mapping is also limited by the
size of the objects to be mapped. E.g. you can map the "position value" (4 bytes), the "speed value" (2 bytes) and
the "acceleration" value (2 bytes) into the same object. Due to the fixed size of a CAN frame this produces less
bus load than transmitting the three objects by 3 individual PDOs. This table shows a possible PDO mapping:
Object no Sub-Index Datatype Size Description
6004h 00h Unsigned32 4 Byte Position value
6030h 01h Integer16 2 Byte Speed value
6040h 01h Integer16 2 Byte Acceleration value
Table 8.54: Example of a mapping-table
The data 1, 2 und 3 (see mapping, Fehler! Verweisquelle konnte nicht gefunden werden. ) are spread over the
PDOs 8 payload bytes. The current payload is 4byte + 2 byte + 2byte = 8 byte. So the PDO is used with 100%
efficiency!
The resulting PDO has this structure:
PDO1:
180h+ID 8 1d 1c 1b 1a 2b 2a 3b 3a
CAN-ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
Table 8.55: Structure of PDO1 (content -> Fehler! Verweisquelle konnte nicht gefunden werden. )
1a, 1b, 1c, 1d = 4 bytes of information 1; 2a, 2b = 2 bytes of information 2; 3a, 3b = 2 bytes der information 3.