EZ Automation EZTouch I/O Flex, Инструкция по эксплуатации

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EZTouchPLC
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Index and Value Registers (Word)
The Index Register data type is represented by an “XR” prefix (e.g. XR1, XR2
etc.). There are 4 XR memory locations available in
EZTouchPLC
. “XR” is a
Read-Write data type and it is mainly used to point to the correct address of “R”
registers. The pointed-to “R” registers data value is stored in “#R” registers.
Value Register data type is represented by a “#R” prefix (e.g. #R1, #R2 etc.).
There are 4 #R memory locations available in
EZTouchPLC
. “#R” is a Read-Write
data type and it is mainly used to read/write value of “R” registers as pointed
out by “XR” registers.
Both XR and #R registers are used in conjunction with each other and provide a
convenient way of addressing R registers.
Example:
Let's assume data values: R59=9874, R8000=32
If XR1=59
Then #R1=9874 (the actual data value of R59)
If XR2=8000
Then #R2=32 (the actual data value of R8000)
XR contains the address of the operand (or specifies a register that contains the
effective address), #R is used to read or write the actual operand. Indirect
addressing is often combined with pre- or post-increment (or decrement)
addressing. This allows the address of the operand to be increased or decreased by
the specified number either before or after using it. Proper usage of XR variables
often saves a lot of programming.