Omron CVM1 Series, Operation Manual

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Ladder Programming Precautions Section 3-4
Example 2:
An existing C1000H/C2000H PLC is set to multi-level mode operation, link #1,
node address 0, and 64 Link Relay bits/Unit, so LR 32 to LR 35 are used as
the transfer area.
In the replacement CVM1/CV-series PLC, use CIO 1032 to CIO 1035 as the
transfer area. Since the Unit is node 0 (polling node), the Number of LR Bits
must be set on the Unit’s DIP switch.
3-4-2 PC Link Status Area
The location of the Status Area used to monitor the PC Link system’s opera-
tion is also different in the C1000H/C2000H and CVM1/CV-series. In the
C1000H/C2000H PLCs, the Status Flags were always in SR 247 to SR 250,
but in the CVM1/CV-series PLCs, the CPU Bus Unit is used for the Status
Flags.
The location of the CPU Bus Unit Status Flags depends on the unit number
set with the Unit Number Setting Switches (UNIT NO.) on the front of the
CVM1-LK401.
The CPU Bus Unit unit number can be set between 00 and 15. Refer to 3-3-1
Setting the Unit Number .)
PC Link Error and
PLC Run Flags
The read-only Status Area contains flags that indicate the operating status of
the PC Link and each PLC connected to the PC Link system.
Flag Allocation in Single-
level Mode The following table shows the location of the PLC Run Flags and PC Link
Error Flags, based on the PLC model and PC Link Unit’s unit number.
Example:
In this example, the existing PC Link system is made up of 8 PLCs and the PC
Link Unit being replaced is node 0 (the polling node). The C1000H/C2000H
flags are as follows:
• The PC Link Error Flags for nodes 1 to 7 are in SR 25009 to SR 25015.
• The PLC Run Flags for nodes 1 to 7 are in SR 25001 to SR 25007
In the CVM1/CV-series PLC, the Status Area depends on the unit number (N).
When the unit number is set to 0, the word CIO 1500 + 25
×
N + 3 = CIO 1503
is equivalent to SR 250 in the C1000H/C2000H. Consequently, change any
ladder program occurrences of SR 250 to CIO 1503.
UNIT
No.
×
10
1
×
10
0
0
0
PLC Run Flags ON when the corresponding PLC is operating normally.
OFF when the corresponding PLC is stopped.
PC Link Error Flags ON when there is a transfer error or a power interruption in the
corresponding PC Link Unit.
OFF when the PC Link Unit is operating normally.
C1000H/
C2000H
CVM1/CV Series PC Link Error Flags PLC Run Flags
(N = Unit number) Bit 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
SR 247 CIO 1500 + 25
×
N 31 30 29 28 27 26 25 24 31 30 29 28 27 26 25 24
SR 248 CIO 1500 + 25
×
N + 1 23 22 21 20 19 18 17 16 23 22 21 20 19 18 17 16
SR 249 CIO 1500 + 25
×
N + 2 15 14 13 12 11 10 9 8 15 14 13 12 11 10 9 8
SR 250 CIO 1500 + 25
×
N + 3 7 6 5 4 3 2 1 0 7 6 5 4 3 2 1 0