Omron NX701-1620 User Manual page 255

 When the instruction was executed while the DB Connection Service was stopped due to an error
 When the instruction was executed after the DB Connection Service was shut down or while the DB
Connection Service was being shut down
 When the DB Connection name specified in the DBConnectionName input variable is not set in any
DB Connection Settings
 When the DBConnectionName input variable is a text string consisting of NULL characters (16#00)
only
 When a space character is included in the text string specified for the DBConnectionName input
variable
 When the DBConnectionName input variable does not end in NULL.
 When more than 32 DB Connection Instructions were executed at the same time
Sample Programming
This section gives sample programming for the following operations.
 Get the status of the DB Connection when the trigger variable changes to TRUE.
 Change the value of the Warning variable to TRUE when the spool usage has exceeded 80%.
Ladder Diagram
 Main Variables
Name
DB_GetConnectionStatus_instance
Trigger
Operating
OperatingEnd
RS_instance
MyStatus
Warning
GetConnectionStatus_OK
NJ/NX-series Database Connection CPU Units User's Manual (W527)
Data type
DB_GetConnectionStatus
BOOL
BOOL
BOOL
RS
_sDBC_CONNECTION_STATUS
BOOL
BOOL
Initial value Comment
--- Instance of DB_GetConnectionStatus
instruction
FALSE Variable used as a trigger for getting
the status of the DB Connection
FALSE The DB_GetConnectionStatus
instruction is executed when this
variable is TRUE.
FALSE This variable changes to TRUE when
the DB_GetConnectionStatus
instruction is completed.
--- Instance of RS instruction
--- This variable is assigned to the
ConnectionStatus output variable
from
DB_GetConnectionStatus_instance.
FALSE This variable changes to TRUE when
the Spool usage has exceeded 80%.
FALSE This variable changes to TRUE when
the DB_GetConnectionStatus
instruction is completed normally.
Appendix A
A
A-67