SIEMENS STL programming for machine Builders in TIA Portal (PART1)
Siemens STL (Statement List) programming is a low-level, text-based language used in Siemens PLCs within the STEP 7 and TIA Portal environments. Because it closely resembles assembly language, STL provides precise control over CPU operations, memory management, and logic execution. It is particularly valuable for applications that require detailed manipulation of Boolean logic, advanced arithmetic operations, or optimized execution speed. While languages like Ladder Logic (LAD) and Function Block Diagram (FBD) are more common for general development due to their readability, STL remains a powerful tool for engineers who need deeper insight into how PLC instructions are executed at the instruction level.
In this lesson, you will learn all the programming elements needed to become proficient in expert-level STL programming. We begin with the fundamentals suited for beginners, ensuring you understand the structure, syntax, and logic flow of STL. From there, the lesson gradually progresses into more advanced topics, helping you gain the confidence and technical skill required to write efficient and reliable STL programs.
By the end of this lesson, you will know how to use STL programming to perform small automation tasks and control simple machines. You will also become familiar with STL functions and function blocks, equipping you with the knowledge needed to design control strategies for medium-sized machinery and even more complex industrial systems. This structured approach will help you transition from basic instruction handling to creating robust, scalable automation solutions.
Curriculum
- 17 Sections
- 151 Lessons
- 62 Weeks
- PART0 | How to manage the Course1
- PART1 | Binary Logic Operation in STL Programming15
- 2.1QEA00 | How is the STL program executed?
- 2.2QEA01 | Basic Functions in Binary Operation
- 2.3QEA02 | Timing Diagram for Binary Operation
- 2.4QEA03 | RLO Negating instruction
- 2.5QEA04 | Nested and complex binary operations in STL (P1)
- 2.6QEA05 | Nested and complex binary operations in STL (P2)
- 2.7QEA06 | Assignment and Flip-Flops timing diagrams
- 2.8QEA07 | Set and Reset Priority in STL
- 2.9QEA08 | Nesting Statement as Intermediate Bit Buffer (Flip-Flop)
- 2.10QEA09 | Edge detection
- 2.11QEA10 | Exercise | STL to FBD conversion
- 2.12QEA11 | Exercise | Extensive Nested STL to FBD conversion
- 2.13QEA12 | Exercise | Complete a Timing Diagram of an STL Logic
- 2.14QEA14 | Exercise | Override selector Block | Min Max selection
- 2.15QEA15 | Exercise | Voter 1OO2 signal quality checks
- PART2 | Move Functions9
- 3.1QEB00 | Load and Transfer instructions
- 3.2QEB01 | Accumulator instructions
- 3.3QEB02 | SFC 20 BLKMOV (Copy memory area)
- 3.4QEB03 | SFC 21 FILL (Initializing a memory area)
- 3.5QEB04 | SFC 81 UBLKMOV (Uninterruptible copying of variables)
- 3.6QEB05 | MOVE_BLK for S7-1500
- 3.7QEB06 | Serialize and Deserialize for S7-1500
- 3.8QEB10 | Exercise | Focus on Accumulator instructions
- 3.9QEB11 | SPARE
- PART3 | Timer Functions14
- 4.1QEC00 | S5 Time data type
- 4.2QEC01 | Pulse Timers for SIMATIC controllers
- 4.3QEC02 | Extended Pulse Timers for SIMATIC controllers
- 4.4QEC03 | On-Delay Timers for SIMATIC controllers
- 4.5QEC04 | Retentive On-Delay Timers for SIMATIC controllers
- 4.6QEC05 | Off-Delay Timers for SIMATIC controllers
- 4.7QEC06 | IEC Timer Functions
- 4.8QEC10 | Exercise | Develop IEC timer to meet Allen Bradley specifications (AB Migration)
- 4.9QEC11 | Exercise | Develop IEC timer with Reset and Remaining Time (AB Migration)
- 4.10QEC12 | Exercise | Control Panel Temperature Monitor | Timer application
- 4.11QEC14 | Exercise | Pulse Generation Variable Period
- 4.12QEC15 | Exercise | How to make an On-Delay Timer with a Pulse Timer
- 4.13QEC16 | Exercise | How to make an Off-Delay Timer with a Pulse Timer (Unsolved)
- 4.14QEC17 | Exercise | How to detect a watchdog failure in a communication data using timers?(Unsolved)
- PART4 | Counter Functions6
- PART5 | Digital Functions | P114
- 6.1QEF00 | Comparison Functions
- 6.2QEF01 | Arithmetic Functions
- 6.3QEF02 | Arithmetic Functions | Chain Calculation
- 6.4QEF03 | Arithmetic Functions | Adding Constants to Accumulator 1
- 6.5QEF04 | Math Functions
- 6.6QEF05 | Conversions Functions
- 6.7QEF06 | Shift Functions and their applications
- 6.8QEF07 | Word Logic
- 6.9QEF08 | Status Bits | Binary Flags
- 6.10QEF09 | Status Bits | Digital Flags
- 6.11QEF10 | Program Flow Control | Jump Functions
- 6.12QEF11 | Binary Result and EN/ENO
- 6.13QEF12 | Jump Distributor
- 6.14QEF14 | Loop in STL
- PART6 | Digital Functions | Examples11
- 7.1QEG00 | Exercise | Allen Bradley LIM | Limit Test Function
- 7.2QEG01 | Exercise | Air Pressure at Altitude Calculation
- 7.3QEG02 | Exercise | BCD to INT with | BCD Validation test
- 7.4QEG03 | Exercise | Extract Real value to several bytes
- 7.5QEG04 | Exercise | Visualize CC1 manipulation in Shift/Rotate functions
- 7.6QEG05 | Exercise | Division result test by using status bits
- 7.7QEG06 | Exercise | My Dint Counter
- 7.8QEG07 | Exercise | Binary Result | Report block internal problems
- 7.9QEG08 | Exercise | Develop My Off-Delay Timer
- 7.10QEG09 | Exercise | The Factorial Calculation with Loop
- 7.11QEG10 | Exercise | SPARE
- PART7 | Pointers , Indirect Addressing and Miscellaneous Topics10
- 8.1QEH00 | End of year Pulse | Time of Day Interrupts
- 8.2QEH01 | End of year Pulse | Use SFC1
- 8.3QEH02 | DCS PLC Time Synchronization
- 8.4QEH03 | Override Block Min and Max Selector
- 8.5QEH04 | Pointers | Basic structure of a generic memory area in S7 architecture
- 8.6QEH05 | Pointers | Area internal pointer structure
- 8.7QEH06 | Pointers | Starting Example for pointer applications
- 8.8QEH07 | Pointers | Area pointer syntax | How to use it in STL
- 8.9QEH08 | Pointers with address registers
- 8.10QEH09 | Exercise | Pointers for analog input processing
- PART10 | Industrial Dryer Control System Design18
- 9.1QEP00 | Control Philosophy of Dryer
- 9.2QEP01 | Program Call Structure
- 9.3QEP02 | Restart Behavior
- 9.4QEP03 | Cyclic Interrupt | Machine impulse Generation
- 9.5QEP04 | General Routines | Main Organization Block | Memory to Outputs
- 9.6QEP05 | Valve Manipulation with Sequence | Machine Pulse
- 9.7QEP06 | Block for calling valve status and HMI report (ENGINE)
- 9.8QEP07 | Block for calling valve simulations (ENGINE)
- 9.9QEP08 | Template Block for valve simulations-FC only (CORE)
- 9.10QEP09 | Template Block for valve status monitoring and HMI report (CORE)
- 9.11QEP10 | Statistics | Template block for Worst Valve | Template Cascade Counter
- 9.12QEP11 | Statistics | Number of cycles and number of starts
- 9.13QEP12 | Statistics | Report Worst Valve due to Failure rate
- 9.14QEP14 | Statistics | Runtime Meter Calculation
- 9.15QEP15 | Function Test | HMI Development in WinCC Professional
- 9.16QEP16 | Function Test | Worst Valve Report
- 9.17QEP16 | HMI Development in WinCC Professional (P2)
- 9.18QEP_SPARE
- PART11 | Main Motor Control and Runtime meter9
- 10.1QES00 | Permissive and conditions to start main motor
- 10.2QES01 | Start Commands | Electrical Pulse| Counting number of starts
- 10.3QES02 | Main Motor Run status and Stop signal
- 10.4QES03 | Warm-Cold start up conditions
- 10.5QES04 | Main Motor Runtime meter
- 10.6QES05 | Main Motor Restart Blocking Bit
- 10.7QES06 | Function Test for Main Motor Control and Runtime meter
- 10.8QES07 | WinCC Professional Project for Main Motor Control and Runtime meter
- 10.10QES08 | Exercise Unsolved | Explain Speed Simulation Section
- PART12 | Analog Channel Failure Evaluation | Hardware Diagnostics in STL8
- 11.1QET00 | Analog Input – Output configuration
- 11.2QET01 | UDT (PLC Data Type) Definition
- 11.3QET02 | OBs for Analog Input – Output Channel failure
- 11.4QET03 | Reading Data Records with SFC59 (RD_REC)
- 11.5QET04 | Program Development (P1)
- 11.6QET05 | Program Development (P2)
- 11.7QET06 | Analog Channel Failure Shut-Down Signal
- 11.8QET07 | Unsolved Exercise | Implement 1oo2 Analog Voter in STL (Prosafe RS Style)
- PART14 | Industrial HVAC Chiller for N2 Generation8
- 12.1QEV00 | SIEMENS STL Programming| Chiller Control Philosophy (P1)
- 12.2QEV01 | SIEMENS STL Programming| Chiller Control Philosophy (P2)
- 12.3QEV02 | SIEMENS STL Programming| Fans, Coolers, Heaters, separation Control Philosophy
- 12.4QEV03 | SIEMENS STL Programming | Chillers Control in STL
- 12.5QEV04 | SIEMENS STL Programming | Heaters Control in STL
- 12.6QEV05 | SIEMENS STL Programming | Oil Coolers Control in STL
- 12.7QEV06 | SIEMENS STL Programming | Condenser Fan Control in STL
- 12.8QEV07 | SIEMENS STL Programming| Condensed Water Separation level control in STL
- PART15 | Exercise | Migration Machine from Allen-Bradley to SIEMENS STL (North America and Australia)11
- 13.1QEW00 | Exercise | ESTOP logic versus Control Circuit Supply Health logic
- 13.2QEW01 | Exercise | Oil Pump A/B Status Management
- 13.3QEW02 | Exercise | Timer On Delay and 1 second impulse
- 13.4QEW03 | Exercise | Setpoint update in each minute | Minute Impulse
- 13.5QEW04 | Exercise | Vibration monitoring logic
- 13.6QEW05 | Exercise | Slide Control Valve Minimum Position Detection
- 13.7QEW06 | Exercise | Oil Separator Heater Interlock Timer
- 13.8QEW07 | Exercise | Oil Header and Oil Difference Pressure Trip
- 13.9QEW08 | Exercise | Make a Pulse Timer with On Delay Timer
- 13.10QEW09 | Exercise | Compressor Auto Unload flag
- 13.11QEW11 | Exercise | Hot Gas to Evaporator Valve controlled by suction pressure(Unsolved)
- PART16 | Exercise | Chemical Treatment Plant control in SIEMENS STL - TIA Portal7
- 14.1QEW20 | Exercise | Single Pump Operation and reusable Faceplate development
- 14.2QEW21 | Exercise | Double Pump in Oily Water sump
- 14.3QEW22 | Exercise | Neutralization and cooling system
- 14.4QEW23 | Exercise | Electrical Pump Logic in STL
- 14.5QEW24 | Exercise | How to reuse logic , HMI Screen and Faceplates for pumps
- 14.6QEW25 | Exercise | Governing logic for Double Pump operation in STL
- 14.7QEW26 | Exercise | Neutralization Logic in STL (Unsolved)
- PART19 | STL Interview Questions5
- 15.1QEX00 | STL Interview Questions | Binary Logic Operation | Unsolved
- 15.2QEX01 | STL Interview Questions | Timer Application | Cycle Break Injection
- 15.3QEX02 | STL Interview Questions | Counter Application | Cycle counting level control
- 15.4QEX03 | STL Interview Questions | Lean Analog smoothening functionality
- 15.5QEX04 | STL Interview Questions | Pinion Spray Off STL Logic
- PART20 | QUIZ1
- PART21 | SPARE4