Siemens SIMOREG DC Master 6RA7028-6DS22 Operating Instructions Manual page 174

Start-Up
The following transfer function is also available:
PKW Request Broadcast
A parameter job (request) is processed simultaneously by all slaves on the bus. The node
address is not used to generate the CAN identifier because this must be set identically on all
slaves utilizing the PKW Request Broadcast function. This common identifier is set in CB
parameter 9 (U719). The corresponding parameter response is made with the CAN identifier
for PKW Response described above.
Notes regarding PKW transmission:
The length of the job and the response is always 4 words. Jobs which apply to all indices of a
parameter (e.g. "Request all indices") are not possible.
As a general rule, the low-order byte (in words) or the low-order word (in double words) is
transferred first. SIMOREG 6RA70 does not use double word parameters itself, these jobs
can only be executed where access is available to technology board parameters (e.g. T400).
The CBC or CB2 does not respond to a parameter request job until the drive data are
available. This normally takes 20 ms. The response times will be longer only if change (write)
jobs including storage of the value in the EEPROM are received from other sources (e.g.
serial basic converter interface), resulting in a delay in job execution.
In certain system states (e.g. initialization states), parameter processing is greatly delayed or
does not take place at all.
The master may not issue a new parameter request job until any current parameter job has
been acknowledged.
Fault and alarm messages:
Alarm A083 (Error Warning)
Errored telegrams are being received or sent and the error counter on the supplementary
board has exceeded the alarm limit.
Errored telegrams are ignored. The data most recently transferred remain valid. If the errored
telegrams contain process data, fault message F082 with fault value 10 may be activated as
a function of the telegram failure time set in U722. No fault message is generated for PKW
data.
Alarm A084 (Bus Off)
Errored telegrams are being received or sent and the error counter on the supplementary
board has exceeded the fault limit.
Errored telegrams are ignored. The data most recently transferred remain valid. If the errored
telegrams contain process data, fault message F082 with fault value 10 may be activated as
a function of the telegram failure time set in U722. No fault message is generated for PKW
data.
7-32
SIEMENS AG
SIMOREG DC Master Operating Instructions
02.00
6RX1700-0AD76