Omron CVM1D, Operation Manual

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6-1-3 I/O Refreshing Limitations
In CVM1D PCs, cyclic refreshing is the only method used to refresh the entire I/O
area. The I/O REFRESH instruction (IORF(184)) can be used to refresh specific
ranges of I/O words.
•
The refreshing method cannot be changed to “scheduled refreshing” or “zero-
cross refreshing” in the PC Setup. It is not possible to change these settings
from Programming Devices.
•
Immediate-refreshing variations (with the “!” prefix) cannot be used in duplex
mode. Operation in the active and standby CPUs might differ in duplex mode.
Immediate-refreshing variations can be used in simplex mode.
•
Interrupt Input Units cannot be used. If an Interrupt Input Unit is mounted, it will
be treated as a normal Input Unit.
The interrupt control instructions (MSKS(153), CLI(154), and MSKR(155))
cannot be used in either simplex or duplex mode. These instructions will be
processed as NOP(000) if they are included in the program.
6-1-4 Memory Card Usage Limitations
When Memory Cards are being used in duplex mode, only the Memory Card
mounted in the active CPU Unit is used during operation. A Memory Card
mounted in the standby CPU Unit will be ignored during operation, but the con-
tents of the Memory Card will be downloaded to the CPU Unit at startup if pin 5 of
the standby CPU Unit’s DIP switch is set to ON.
Memory Card read/write operations cannot be performed from the program and
the Memory Card instructions (FILR(180), FILW(181), FILP(182), and
FLSP(183)) cannot be used in the CVM1D. These instructions will be processed
as NOP(000) if they are included in the program.
6-1-5 CPU Processing after Power Interruptions
In CVM1D PCs, a power interruption signal is output when the CPU detects a
power supply voltage below 85% of full power. The momentary power interrup-
tion time is fixed at 0 ms, so power interruptions cannot be processed as mo-
mentary power interruptions. When the power supply voltage returns to the mini-
mum value, PC operation will restart with initialization.
Power OFF Interrupts are not processed.
The following settings cannot be changed in the PC Setup. Changed settings will
be ignored.
Parameter Setting Operation
F:Execute
control 1 S:Error on power
off Fixed at “Do not treat as an error.” Determines whether to stop operation
based solely on the size of the DC
Power Supply’s voltage drop when a
P:Power break Fixed at “Momentary power interruption
time = 0 ms.”
(No momentary power interruptions)
Power Supply’s voltage drop when a
power interruption or voltage drop
occurs, regardless of the length of the
interruption.
G:Execute
control 2 D:Power OFF
interrupt Fixed at “Do not execute Power OFF
interrupt.” When the power supply voltage
returns to minimum values, operation
starts as if power was turned on.
B:Startup hold Fixed at “Do not hold.” The I/O memory will be refreshed
once the PC has stopped.
PC Operation
Section 6-1