Omron SYSMAC CP Series, Руководство пользователя

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5 I/O Memory
5-4
CP2E CPU Unit Software User’s Manual(W614)
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Counter Area (C)
There are two parts to the Counter Area: the Counter Completion Flags and the Counter Present
Values (PVs).
Up to 256 counters with counter numbers C0 to C255 can be used.
These words retain their content when the PLC is turned ON or the operating mode is switched
between PROGRAM mode and RUN or MONITOR mode.
Automatically retained in the built-in non-volatile RAM even if the power supply is interrupted.
• Counter Completion Flags
Each Counter Completion Flag is accessed as one bit using the counter number.
A Completion Flag is turned ON when the set value of the counter is reached.
• Counter PVs
Each counter PV is accessed as one word (16 bits) using the timer number.
The PVs count up or down as the counter operates.
Refer to 5-7 Counter Area (C)
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Index Registers (IR)
Index registers (IR0 to IR15) are used to store PLC memory addresses (i.e., absolute memory
addresses in RAM) to indirectly address words in I/O memory.
Refer to 5- 8 Index Regi s ter s (IR)
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Data Registers (DR)
Data registers (DR0 to DR15) are used together with Index Registers. When a Data Register is input
just before an Index Register, the content of the Data Register is added to the PLC memory address
in the Index Register to offset that address.
Refer to 5-9 Data Regi s ter s (DR)
System Areas contain bits and words with preassigned functions.
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Auxiliary Area (A)
The words and bits in this area have preassigned functions.
Refer to A-2 Auxiliary Area Allocation s by Addre ss
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Condition Flags
The Condition Flags include the flags that indicate the results of instruction execution, as well as the
Always ON and Always OFF Flags.
The Condition Flags are specified with global symbols rather than with addresses. For example: P_on
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Clock Pulses
The Clock Pulses are turned ON and OFF by the CPU Unit ’ s internal timer.
The Clock Pulses are specified with global symbols rather than with addresses. For example: P_0_02
System Areas