Siemens SIMATIC TIWAY 1 User Manual page 37

OPERATION AND APPLICATION
The BROADCAST NETWORK DATA TRANSFER command will send the
Primitive to all logically connected secondary devices on the network and is
provided for backward compatibility with the original TIWAY I Host Adapter.
The Broadcast/Poll sequence is more efficiently handled with macros discussed
in Paragraph 2.10. Unlike the SEND NETWORK DATA command, the
responses from the secondaries do not automatically return. If the command is
accepted, the command code will be returned, then your applications software
MUST issue a POLL command to each secondary to collect the Primitive
response.
You should
NETWORK DATA TRANSFER command if your
network
Transmitters (ITTs) as secondary devices or
you could loose responses. Also, sending a
BROADCAST NETWORK DATA TRANSFER
command when your adapter is configured as
either an MHIU or an HIU will cause an
network HDLC error to be logged even though
the information was received. This error will
be included in the statistics from the READ
SECONDARY DIAGNOSTICS, REPORT HIU
STATUS, REPORT
SECONDARY STATISTICS and the REPORT
NETWORK
STATISTICS commands.
The POLL command can only be used by an adapter configured as an
MHIU/EHA, however, the broadcast/poll sequence can be implemented in other
operating modes with macros. Example 2–1 is a typical sequence for the
broadcast/poll commands.
CAUTION
not issue the
contains Intelligent
NETWORK
MANAGER
2–27
BROADCAST
Tank
MANAGER
NETWORK
UNILINK HOST ADAPTER
USER MANUAL