| The Citect device driver for
communications to the S7-300 and S7-400 range of PLCs uses the
Siemens S7 SAPI functions, and tests using the CP5412A2 have been
successful. The CP5412A2 has allowed communications directly to the
MPI port on the processor at 187kbaud, and to the communications
processor, the CP342-5DP at 1.5Mbaud.
The CP5411 however has a design feature that requires PC memory
reserved between 15Meg and 16Meg in RAM. As most standard PCs on
the market these days do not support the exclusion of this area of
memory, the PC would need to have less than 15Meg installed and
would likely be limited to a total of 12Meg of RAM, insufficient
for most Windows operating systems and almost impossible to obtain.
(We have been notified that Siemens Nixdorf PCs allow the exclusion
of this area of memory. As most of our customers do not use these
PCs the following comments are still applicable) As a result,
although the Citect driver will support the use of the CP5411, Ci
Technologies will not support the use of the CP5411 in the near
future (however this situation may change without notice).
Customers choosing to use the CP5411 with a Citect system will be
solely responsible for this course of action.
The CP5412A2 also presents the greatest performance, and we are
recommending this card as a basis for low and medium speed
communications, with Ethernet for high speed communications (not
tested at this stage).
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