Chapter 5. Ladder and Functional Block Programming
Programs for microprocessor-based systems have to be loaded in machine code, a sequence of binary code numbers to represent the program instructions. However, assembly language based on the use of mnemonics can be used; for example, LD is used to indicate the operation required to load the data that follows the LD, and a computer program called an assembler is used to translate the mnemonics into machine code. Programming can be made even easier by the use of the so-called high-level languages, such as C, BASIC, Pascal, FORTRAN, and COBOL. These languages use prepackaged functions, represented by simple words or symbols descriptive of the function concerned. For example, with C language the symbol ...

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