Programming Languages

Ladder Logic(LD)

                             Ladder logic is a programming language that creates and represents a program through ladder diagrams that are based on circuit diagrams. Ladder Diagram (LD) is a graphic representation of boolean equations, combining contacts (input arguments) with coils (output results).

Instruction List(IL)

                              It is a  low level language and resembles assembly.Program control  is achieved by jump instructions and function calls (subroutines with optional parameters). Instruction list (IL)  uses very simple instructions similar to the original mnemonic programming languages developed for PLCs.  

Functional block Diagram(FBD)

                               FBD is a graphical language for programmable Logic controller design ,that can describe the function between Input variables and Output variables .A function is described as a set of elementary blocks. Input and output variables are connected to blocks by connection lines   

               

Structure text(ST)

                             The programming language is text- based ,compared to the graphic-based ladder diagarams 

Sequential Flow Chart(SFC)

                     SFC is Programming method in PLC to execute the logic with step wise.