RACOM RipEX2, Руководство пользователя

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The PR2000 protocol is implemented in a fully transparent manner. The original protocol frames are
transported over the RipEX network in their entirety.
7.1.3.3.11. Siemens 3964(R)
The 3964 protocol is utilized by the Siemens Company as a Point-to-Point connection between two
controllers. Meanwhile it has developed into an industry standard that can be found on many devices
as a universal communications interface. 3964R is the same as 3964, in addition it only uses BCC
(Block Check Character). 3964(R) handles only the link layer (L2 in OSI model), hence RipEX uses a
similar way to read “SCADA address” as in UNI protocol.
There is a handshake STX(0x02) – DLE(Ox10) on the start of communication and DLE+ETX – DLE
on the end. This handshake is performed by RipEX locally, it is not transferred over the RipEX network.
Communication goes as follows:
LocalRTU -> STX -> LocalRipEX
LocalRipEX -> DLE -> LocalRTU
LocalRTU -> DATA+DLE+ETX+BCC -> LocalRipEX
LocalRipEX -> DATA -> RemoteRipEX*
LocalRipEX -> DLE -> LocalRTU
RemoteRipEX -> STX -> RemoteRTU
RemoteRTU -> DLE -> RemoteRipEX
RemoteRipEX -> DATA+DLE+ETX+BCC -> RemoteRTU
RemoteRTU -> DLE -> RemoteRipEX
* only this packet is transferred over the RipEX network, all the other ones are handled locally.
87 © RACOM s.r.o. – RipEX2 Radio modem & Router
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