Specifications

Advanced Configuration Features
134
31004624 8/2009
RTP Response Block Words Definitions
The following list shows RTP response block words:
The toggle+CMD echo bytes are located at the end of the register range to let you
validate the consistency of the data wrapped within these bytes (in case RTP
response block words are not updated in a single scan). The NIM updates the status
byte and the 4 data bytes (if applicable) before updating the toggle+CMD echo
bytes in Modbus register 45303 and 45306 to equal the value of the toggle+CMD
byte of the corresponding RTP request. You must first check that both toggle+CMD
bytes match the toggle+CMD byte in the RTP request block before making use of
the data inside the RTP response block.
WARNING
UNINTENDED EQUIPMENT OPERATION
Write all bytes in the RTP request before you set the toggle+CMD and
toggle+length bytes to the same new value.
Failure to follow these instructions can result in death, serious injury, or
equipment damage.
Modbus
Address
Upper Byte Lower Byte Data Type Attribute
45303 status (the most significant
bit is used to indicate
whether RTP service is
enabled: MSB=1 means
enabled)
toggle + CMD
echo
unsigned 16 RO
45304 data byte 2 data byte 1 (LSB) unsigned 16 RO
45305 data byte 4 (MSB) data byte 3 unsigned 16 RO
45306 - toggle + CMD
echo
unsigned 16 RO
NOTE: The RTP response block is also presented in the manufacturer specific area of the
CANopen fieldbus as an object with a dedicated index of 0x4100 and sub-index 1 to 4
(data type = unsigned 16, attribute = RO).