TwinCAT provides internal system information via the Tc2_System library. You can check if the current cycle is the very first one by looking at the system task info.
IF bFirstScan THEN // Perform Initialization Tasks here iTargetVelocity := 1500; bMachineReady := FALSE; END_IF // All other machine logic goes here... // The very last line of the program: bFirstScan := FALSE; Use code with caution. 2. Using FB_GetCurTaskIndex (The Pro Method)
Never make your First Scan bit a RETAIN or PERSISTENT variable. It needs to reset every time the PLC power cycles.
Ensuring your sequences (SFC) start at "Step 0."
TwinCAT provides internal system information via the Tc2_System library. You can check if the current cycle is the very first one by looking at the system task info.
IF bFirstScan THEN // Perform Initialization Tasks here iTargetVelocity := 1500; bMachineReady := FALSE; END_IF // All other machine logic goes here... // The very last line of the program: bFirstScan := FALSE; Use code with caution. 2. Using FB_GetCurTaskIndex (The Pro Method)
Never make your First Scan bit a RETAIN or PERSISTENT variable. It needs to reset every time the PLC power cycles.
Ensuring your sequences (SFC) start at "Step 0."