MaxStream XStream X09-001 Series, Руководство по эксплуатации продукта

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XStream™ OEM RF Module – Product Manual v5.x00 [2006.02.24]
4.1. Addressing
Each RF packet contains addressing information that is used to filter incoming RF data. Receiving
modules inspect the Hopping Channel (HP parameter), Vendor Identification Number (ID
parameter) and Destination Address (DT parameter) contained in each RF packet. Data that does
not pass through all three network security layers is discarded.
Figure 4 ‐ 01. Filtration layers contained in the RF packet header
4.1.1. Address Recognition
Transmissions can be addressed to a specific module or group of modules using the DT
(Destination Address) and MK (Address Mask) parameters. The transmitting module dictates
whether the packet is intended for a specific module (local address) or multiple modules (global
address) by comparing the packet’s DT parameter to its own MK parameter.
Figure 4 ‐ 02. Local Packets vs. Global Packets (Transmitting Module)
TX_DT = Transmitter Destination Address
TX_MK = Transmitter Address Mask
Note: When TX_DT = 0xFFFF (default), RF packets are global and are
received by all modules within range. (Receivers do not send ACKs.)
A receiving module will only accept a packet if a packet is addressed to it (either as a global or
local packet). The RX module makes this determination by inspecting the destination address of
the RF packet and comparing it to its own address and mask. The Destination Address of the TX
module is logically “ANDed” with the Address Mask of the RX module.
Figure 4 ‐ 03. Address Recognition (Receiving Module)
TX_DT = Transmitter Destination Address
RX_DT = Receiver Destination Address
RX_MY = Receiver Source Address
NOTE: For more information regarding addressing and masks, refer to Application Note ‘XST-
AN004b’. (Located on the MaxStream CD and on the web: www.maxstream.net)
© 2006 MaxStream, Inc. Confidential and Proprietary 36
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