GE GFK-2958E, Руководство пользователя

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Chapter 8 Commissioning
GFK-2958E RSTi-EP User Manual 352
8.3.2 Configuring Module Data Areas
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To configure module data areas: Right-click the Module node in the Hardware
Configuration , and select Configure . The Parameter Editor window for the module displays.
The values for read-only parameters are supplied from the GSD text file that defines the PROFIBUS
module's characteristics. Most devices have one data area with inputs, outputs or both. Some
devices have multiple data areas that are shown as additional rows.
Data Area Parameters
Area This value is an index beginning at 1. Read-only.
Type Specifies whether the data is input or output as well as type, digital or analog. Value can be Digital In,
Analog In, Digital Out, or Analog Out.
Ref Address Specifies the memory area that is used to map the data area. Regardless of the reference type used,
input areas are considered as consumed and cannot overlap, while output areas are considered as
produced and may overlap.
Allowable Ranges: %AI, %AQ, %I, %Q, %G, %R, %W, %T, %M.
If the number of bytes is odd, analog memories are not allowed and selections are limited to: %I, %Q,
%G, %M
Length Specifies the length of the reference. Includes the entire data area by default. If set to 0, the data area
is not mapped.
For discrete memories, the allowable range is [0, 8, 16, …, X]
For analog memories, the allowable range is [0, 1, 2, …, X]
Swap Bytes The swap bytes field is used to manipulate the byte order. Because PROFIBUS devices often do not
follow the standard, the ability to change byte ordering is provided. The analog areas travel in MSB
and should be swapped if LSB is required.
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If Type is Digital and the module has an odd number of bytes, Swap Bytes is set to False (no
swapping) and read-only.
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If Type is Digital and the module has an even number of bytes, default is set to False. Setting
Swap Bytes to True causes the LSB and MSB to be swapped before the data is mapped into PLC
memory.
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If Type is Analog, default is set to False. Setting Swap Bytes to True causes the LSB and MSB to be
swapped before the data is mapped into PLC memory.
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For EP-5111, EP-5112, EP-5212, EP-5442 and EP-5422 modules, user should set Swap Bytes to
true. In application if the user want to access the DWORD for these modules, use SWAP_DWORD
function block.