Omron CP1L-EL20DR-D, Руководство по эксплуатации

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Overview of I/O Memory Area Section 4-1
Counter PVs
The PVs are read and written as words (16 bits). The PVs count up or down
as the counter operates.
Condition Flags These flags include the Arithmetic Flags, such as the Error Flag and Equals
Flag, which indicate the results of instruction execution as well as the Always
ON and Always OFF Flags. The Condition Flags are specified with symbols
rather than addresses.
Clock Pulses The Clock Pulses are turned ON and OFF by the CPU Unit’s internal timer.
These bits are specified with symbols rather than addresses.
Task Flag Area (TK) A Task Flag will be ON when the corresponding cyclic task is in executable
(RUN) status and OFF when the cyclic task hasn’t been executed (INI) or is in
standby (WAIT) status.
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 mem-
ory. The Index Registers can be used separately in each task or they can be
shared by all tasks.
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. The Data Registers can be used separately in each task or they
can be shared by all tasks.
4-1-3 Clearing and Holding I/O Memory
Note 1. Mode changed from PROGRAM to RUN/MONITOR or vice-versa.
2. The PLC Setup’s IOM Hold Bit Status at Startup setting determines wheth-
er the IOM Hold Bit’s status is held or cleared when the PLC is turned ON.
Area
Mode changed
1 Fatal error generated
PLC power turned ON
Execution of FALS Other fatal errors PLC Setup set to
clear IOM Hold Bit
status
2
PLC Setup set to
hold IOM Hold Bit
status
2
IOM Hold
Bit OFF
IOM Hold
Bit ON
IOM Hold
Bit OFF
IOM Hold
Bit ON
IOM Hold
Bit OFF
IOM Hold
Bit ON
IOM Hold
Bit OFF
IOM Hold
Bit ON
IOM Hold
Bit OFF
IOM Hold
Bit ON
CIO
Area I/O Area Cleared Retained Retained Retained Cleared Retained Cleared Cleared Cleared Retained
Serial PC Link Area
Internal I/O Area
Work Area (W) Cleared Retained Retained Retained Cleared Retained Cleared Cleared Cleared Retained
Holding Area (H) Retained Retained Retained Retained Retained Retained Retained Retained Retained Retained
Auxiliary Area (A) Status treatment depends on address.
Data Memory Area (D) Retained Retained Retained Retained Retained Retained Retained Retained Retained Retained
Timer Completion Flags (T) Cleared Retained Retained Retained Cleared Retained Cleared Cleared Cleared Retained
Timer PVs (T) Cleared Retained Retained Retained Cleared Retained Cleared Cleared Cleared Retained
Counter Completion Flags (C) Retained Retained Retained Retained Retained Retained Retained Retained Retained Retained
Counter PVs (C) Retained Retained Retained Retained Retained Retained Retained Retained Retained Retained
Task Flags (TK) Cleared Cleared Retained Retained Cleared Cleared Cleared Cleared Cleared Cleared
Index Registers (IR) Cleared Retained Retained Retained Cleared Retained Cleared Cleared Cleared Retained
Data Registers (DR) Cleared Retained Retained Retained Cleared Retained Cleared Cleared Cleared Retained