Siemens SIMATIC TIWAY 1 - Manual (Page 16)

OPERATION AND APPLICATION
UNILINK HOST ADAPTER 2–6
USER MANUAL
2.3.2 Network Manager Function
Acting as the network primary, the Network Manager function is responsible
for controlling the message traffic on the TIWAY I network as shown in Figure
2–5. It receives the requests from HIUs and stores them in a NM buffer, routes
them to the designated secondary devices, and returns the secondary response
to the HIU that issued the request. There can be only one adapter configured
with the Network Manager function in any particular TIWAY I network.
This function will only process Network Manager commands. These commands
control the TIWAY I network operations, return network statistical information
and handle the background monitor and redundant media switching
operations. All network requests and responses are queued in the Network
Manager buffers area.
NM
Manages the message traffic on
the TIWAY I network.
Uses memory for:
Network Buffers
Network Stations
Figure 2–5 Network Manager Function