Mitsubishi Electric 09R927, Руководство по структурному программированию

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3 Function Construction
3.1 Applied Function Expression and Execution Type
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FXCPU Structured Programming Manual
(Application Functions)
3. Function Construction
This chapter explains the construction of applied functions.
3.1 Applied Function Expression and Execution Type
Applied function and argument
• The name expressing the contents is given to each function.
For example, the function name "SHL (bit shift left)" is given.
• Each function consists of arguments which indicate I/O data used in the function.
_IN ( ) : An argument whose contents do not change even if the function is executed is called
"source", and expressed in this symbol.
*1 ( ) : An argument whose contents change when the function is executed is called "destination",
and expressed in this symbol.
K1 ( ) : Arguments not regarded as source or destination are expressed in "m", "n", etc.
Argument target devices
• The input variable (label or device) specifies the target.
• Bit device themselves such as X, Y, M and S may be handled.
• Bit devices may be combined in a way "KnX", "KnY", "KnM" and "KnS" to express numeric data.
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FX Structured Programming Manual (Device & Common)
• Current value registers of data registers (D), timers (T) and counters (C) may be handled.
• When handling 32-bit data in structured programs, you cannot specify 16-bit devices directly, different from
simple projects.
Use labels when handling 32-bit data.
You can specify 32-bit counters directly, however, because they have 32-bit length. Use global labels
when specifying devices.
When 32-bit data is handled, two consecutive 16-bit data registers D are combined.
For example, when data register D0 is defined as an argument of a 32-bit instruction by a label, 32-bit data
stored in D1 and D0 is handled. (D1 offers high-order 16 bits, and D0 offers low-order 16-bits.)
When the current value register of a timer or counter is used as a general data register, it is handled in the
same way.
SHL_E
EN ENO
*1
D10 D0 _IN
_N K1
s
d
n