© Microhard Systems Inc.
45
5.0 Network Topologies
Example:
5 Slaves, configured with PMP defaults (&F2). Unit Addresses: 3, 7, 10, 15, and 21.
UA 3 has some data, 7 has no data, 10 has data, 15 is powered-off, and 21 has data but its
RF connection is very intermittent due to an intermittent outdoor antenna connection.
Master has been configured as PMP default Master (&F1). Clean RF environment.
Changes to be made to the Master:
S244=1
S251=3
ATT0=3
ATT1=7
ATT2=10
ATT3=15
ATT4=21
ATT5=0 (this terminates the list)
The Master will ‘poll’ (give the opportunity to transmit) the Slave with UA 3. This Slave will
transmit all of its data and then inform the Master of same.
On the next hop, the Master will sequence to the next modem, UA 7. Slave 7 will inform the
Master it has no data and on the next hop, the Master will sequence to UA 10.
Slave 10 will transmit its data and inform the Master when complete.
The Master then polls unit 15, no response. On the next hop interval, the Master will poll unit
15 again: no response. It will poll one more time on the following hop interval and, with no
response, will move on to poll UA 21 which has data and sends it to the Master—but due to
the faulty outdoor antenna connection, the Master does not receive the message from the
Slave indicating that it has sent all of its data, so the Master will wait for the value of S251 (3
hops) for such a message from the Slave before moving on to begin the cycle again at UA 3.
