Cirronet HopNet 10 Series, Руководство пользователя

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Multipoint Networks
800281 Rev. B HopNet Family of Products 49
This packet carries user data. The handle number is the handle of the receiving
remote. When data is being sent from a remote to the base, no handle number is
required. User data of up to 212 bytes for each remote or 208 bytes for each base
may be carried per data packet, but no more than is specified by the
maximum
data length
parameter. The radio will not break up a packet over multiple hops.
Packets with a data length greater than maximum data length will not be sent and
will be discarded. This parameter is variable and depends on the number of
remotes currently registered.
Handle 63 is reserved for broadcast packets from the base to all remotes.
Acknowledgment requests are not supported for broadcasts. For this reason, it is
a good idea to send broadcast messages several times to increase the odds of
reaching all remotes.
Connect Packet
1110 1001 10HH HHHH RRRR TTTT 00NN NNNN
<3-byte remote ID> (base, receive only)
H : handle number (0-62)
R : receive sequence number (from previous cell)
T : transmit sequence number (from previous cell)
N : network number of the previous base (if roamed)
1110 1001 10HH HHHH RRRR TTTT 00NN NNNN
<3-byte base ID> (remote, receive only)
H : handle number (0-62)
R : receive sequence number
T : transmit sequence number
N : network number of base
Remotes must go through an automatic registration process when roaming from
one base to another, after loss of contact, or when acquiring a base signal for the
first time after power up. The base then assigns the remote a handle value, may
or may not assign it a dedicated time slice depending on the user settings, and
notifies the user application of the new remote with a connect packet.
The network number of the last base the remote was connected to is given to aid
user software in resending orphan packets that may have been sent to the
remote's previous cell. If the remote has been powered up for the first time and
this is the first base contacted, the last base ID will be reported as
80H .
Disconnect Packet (base only, receive only)
1110 1001 11HH HHHH 0111 1111
H : handle number (1-62)
When a remote goes out of range or roams to another cell, the base issues a
disconnect packet to indicate that the remote is no longer available.