Start / stop of cyclic logging with FB_DBCyclicRdWrt
Download "Example Start / Stop of the cyclic log" sample2.zip
In this example the start and stop of the cyclic log out of the PLC will be shown.
Used database type | MS Compact SQL |
Compatible databse type | ASCII, MS SQL, MS Compact SQL, MS Access, MySQL, PostgreSQL, DB2, Oracle, InterBase/Firebird |
Used function blocks | FB_DBCyclicRdWrt |
Integrated libraries | "TcDatabase.lib", "TcSystem.lib","TcBase.lib","TcStandard.lib" |
Download data list | FB_DBCyclicRdWrt_Sample.pro, CurrentConfigDataBase.xml, TestDB_Cyclic.sdf |
In this example the cyclic log function will be started or stopped by toggling of the bStartStop variable.
At a positive edge at the bExecute input the cyclic log operation starts. At a negative edge this will be stoped.
Variable declaration (PRG DataTypes)
PROGRAM DataTypes
VAR
DBSrv_DT_INT : INT;
DBSrv_DT_UINT : UINT;
DBSrv_DT_DINT : DINT;
DBSrv_DT_UDINT : UDINT;
DBSrv_DT_REAL : REAL;
DBSrv_DT_LREAL : LREAL;
DBSrv_DT_BYTE : BYTE := 16#A1;
DBSrv_DT_BOOL : BOOL;
DBSrv_DT_MYSTRUCT : ST_MyStruct;
DBSrv_DT_ARRAY : ARRAY [0..19] OF UDINT;
DBSrv_DT_WORD : WORD;
DBSrv_DT_DWORD : DWORD;
END_VAR
Structure ST_MyStruct
TYPE ST_MyStruct :
STRUCT
iValue1 : INT;
iValue2 : UINT;
iValue3 : BOOL;
iValue4 : REAL;
END_STRUCTEND_TYPE
Variable declaration
PROGRAM MAIN
VAR
fbDBCyclicRdWrt1: FB_DBCyclicRdWrt;
bCyclic : BOOL :=TRUE;
bBusy_Cyclic : BOOL;
bErr : BOOL;
nErrID : UDINT;
sSQLState : ST_DBSQLError;
END_VAR
PLC Program
DataTypes;
fbDBCyclicRdWrt(
sNetID := ,
bExecute := bCyclic,
tTimeout := t#15s,
bBusy => bBusy_Cyclic,
bError => bErr,
nErrID => nErrID,
sSQLState => sSQLState);
To use this example, you need to pass over the NetID of the ADS device (on which the TwinCAT Database Server is installed) to the input sNetID.
If you start the program and set the bCyclic variable to TRUE, all variables will be logged, that are declared in the symbol group of the XML-configuration data.
 | All the Microsoft SQL Compact databases that are declared in the XML configuration file must exist. They are not generated automatically. |