Functional overview, Products in the environment, Product compatibility – ProSoft Technology MVI56-S3964R User Manual
Page 53: 3964r protocol overview, The 3964r protocol in general, E 53)
Reference MVI56-S3964RT
♦ TControlLogix PlatformT
TSiemens 3964R ProtocolT
ProSoft Technology, Inc.
Page 53 of 78
While in 3964R with RK512 mode on PRT1 and PRT2, evaluation of the
header information DB (data block), DW (data word) and coordination bytes 9
and 10 is possible
Communication activity and diagnostics are available through LEDs and
acknowledgment telegrams
Ladder Logic
Ladder logic programming in the ControlLogix processor is required in order to
enable and support the Siemens 3964R protocol functionality. The ladder
program handles the encoding/decoding of data transferred from the module as
well as the initiation of protocol-specific functionality in the module. Example
ladder programs are provided with the module to simplify the implementation of
the module in the user application.
5.2 Functional
Overview
5.2.1 Products in the Environment
The 3964R protocol can be installed in all local ControlLogix chassis with at least
one controller.
You can obtain more information about ControlLogix and the ControlLogix
environment through your Rockwell Automation branch office.
Product Compatibility
The communication between the MVI56 and the ControlLogix processor is
realized through the module's Input/Output Images.
5.2.2 3964R Protocol Overview
The 3964R Protocol in General
The 3964R protocol defined by Siemens is used for bi-directional data exchange
between two peers through a bit-serial point-to-point connection. This protocol
may be additionally embedded in the RK512 telegram level. If 3964R is used with
RK512, each participant can send jobs to its partner and has read (DB-FETCH)
and write access (DB-SEND) to the partner's data. The data exchange is realized
in the form of messages and response messages. The maximum user data
volume is 512 byte per job and 128 byte per message.
3964R without RK512 allows only block wise sending and receiving of data. The
detailed handshake procedure through messages and response messages is not
applicable in this case.
April 17, 2008