Microhard Systems MHX-900, Руководство по эксплуатации

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18 MHX-900 Operating Manual: Chapter 3 Configuration Options
S Register 113 - Retransmissions (Master Point to
Multipoint)
In a multipoint system, the Master does not receive acknowledgments from
Slaves, and therefore has a slightly modified parameter called
Retransmissions. The Master will retransmit each data packet exactly the
number of times defined by the Retransmissions parameter. The Master
retransmits once per hopping interval until the limit is reached.
S Register 114 - Address Header
A packet parameter unique to Master - Point-to-Multipoint is the Address
Header parameter. The allowable settings are:
*1 Disabled
2 Binary
3 Text
When the Master receives a packet from a Slave, it has the option of
attaching an address header at the beginning of each packet.
Option 2 will attach two bytes of binary data that represent the Slave Unit
Address. The first byte is MSB.
Option 3 will attach five bytes of data that represent the text version of the
Slave Unit Address. The Maximum Packet Size includes the Address
Header. For example, if the Maximum Packet Size is set to 128 and the
Text Address Header option is selected, then the Master will tell the Slave
to send a maximum of 123 bytes.
No address header is attached when Option 1) is used. In this case, it is up
to the equipment connected to the Slave to attach an address header of some
sort so that the Master equipment can determine the source of the data
transmission.
S Register 115 - Packet Repeat Interval
A parameter that is specific to the Slave in multipoint operation is the
Repeat Interval .
The allowable settings are:
1 1...1
2 1...3
3 1...7
4 1...15
5 1...31
6 1...63
7 1...127
*8 1...255
This parameter defines a range of random numbers that the Slave will use as
the next slot in which it will attempt to send the packet. For example, if
Option 3 (1...7) is selected, and the random number generator picks 5, then
the Slave will transmit after five time slots. A Slave will transmit a
maximum of once per hopping interval. The Slave will transmit more
frequently when a Repeat Interval with a smaller range is selected. Choose
1) for the most frequent repeats and choose 8) for the least frequent repeats.