Omron CVM1-CLK21, Operation Manual

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105
Checking Data Link Status Section 5-4
3. When the data link status area is set in the IR, CIO, or LR Area, the data
link status will be instantaneously set to 0 when the mode of the PC’s CPU
Unit is changed.
The flags in the data link status operate as follows:
The Data Link Participation Flag and the PC Status Flag can be used to see if
the system has started normally. These flags, however, cannot be used to
detect communications errors. Use the Communications Error Flag and PC’s
CPU Unit Error Flag to detect errors.
If the Local Node Data Link Participation Flag is OFF, the previous status will
be maintained as the data link status and may not be correct. Make sure that
the Local Node Data Link Participation Flag is ON before checking data link
status.
Note The following Local Node Data Link Participation Flags are available.
CS/CJ-series, CVM1, CV-series PCs:
Bit 15 in 1500 + 25 x unit 6
C200HX/HG/HE PCs: SR 25205
CQM1H-series PCs: IR 9015
The data link status storage area is set as follows:
Name Function
Data link participation The corresponding flag will turn ON if the node has never
participated in the data link normally. The flag will not turn
OFF once it has turned ON even if the node is no longer par-
ticipating in the data links.
Communications
error The corresponding flag will turn ON if continuous data link
data cannot be received from the node, e.g., due to a cable
break. The flag will turn OFF again if normal data is received.
PC’s CPU Unit error The corresponding flag will turn ON if the CPU Unit has a
fatal error, non-fatal error, or watchdog timer error. The flag
will turn OFF again if the node returns to normal.
The status of this flag is based on data sent from the node
and will not turn ON if data cannot received, e.g., due to a
Communications Error. Make sure that the Communications
Error Flag is OFF before checking this flag.
PC status The corresponding flag will turn ON if the user program is
being executed in the CPU Unit. It will turn OFF is the user
program is not being executed.
The status of this flag is based on data sent from the node
and will not turn ON if data cannot received, e.g., due to a
Communications Error. Make sure that the Communications
Error Flag is OFF before checking this flag.
Data link
mode
PC and
operating level
First data link
status word
Setting range Default status
Automatic CS/CJ-series PC Specify in
DM 30000 + 100
×
N + 7
16 words between
CIO 000 and 6640 CIO 1500 + 25
×
N + 7 to 22
C200HX/HG/HE
Level 0 Specify in DM 6407 16 words between
IR 000 and IR 220 or
IR 300 to IR 496 IR 239 to IR 241 (see note b))
C200HX/HG/HE
Level 1 Specify in DM 6427 IR 243 to IR 245 (see note b))
CVM1 or CV-
series PC Specify in DM 2000
+ 100
×
N + 7
16 words between
CIO 000 and 2540 CIO 1500 + 25
×
N + 7 to 22
CQM1H-series
PC Specify in DM 6407 16 words between
IR 000 and IR 232 IR 91 to IR 93 (see note b))