Appendix
Communication with MotionBus/system bus (CAN)
Process data transfer
449
EDBCSXS064 EN 4.0
Identifier
User data (8 bytes)
Control word
00
hex
00
hex
00
hex
00
hex
00
hex
00
hex
11 bits
LOW
byte
HIGH
byte
Fig. 13−4
Structure of process data input telegram (RPDO)
Process data output telegram (TPDO)
ƒ
The process data output telegram reports status information from the controller.
Status information can be as follows:
– Current status of the controller
– Status of the digital inputs
– States about internal analog values
– Fault/error messages
This information enables the higher−level host system (PLC) to respond accordingly.
ƒ
The status word 1 is transmitted in byte 1 and 2 of the user data.
ƒ
In byte 3 and 4 of the user data, the extended status word 2 can be optionally
transferred.
Identifier
User data (8 bytes)
Status word 1 Status word 2
(optional)
00
hex
00
hex
00
hex
00
hex
11 bits
LOW
byte
HIGH
byte
LOW
byte
HIGH
byte
Fig. 13−5
Structure of process data output telegram (TPDO)