Which language uses mnemonics such as LD and ST?

Which language uses mnemonics such as LD and ST?

• A. Instruction List
• B. Ladder Diagram
• C. Function Block Diagram
• D. Structured Text

Answer: (A)

Mnemonics like LD and ST come from an instruction-based, low-level PLC language that mirrors assembly-style coding. This style is Instruction List, one of the IEC 61131-3 languages. In Instruction List you write simple operations as codes: LD loads a value into the accumulator, and ST stores it to a destination. This contrasts with the other languages, which are graphical or higher-level textual forms and use different syntax rather than opcode-like mnemonics. So, the language that uses LD and ST is Instruction List.

Mnemonics like LD and ST come from an instruction-based, low-level PLC language that mirrors assembly-style coding. This style is Instruction List, one of the IEC 61131-3 languages. In Instruction List you write simple operations as codes: LD loads a value into the accumulator, and ST stores it to a destination. This contrasts with the other languages, which are graphical or higher-level textual forms and use different syntax rather than opcode-like mnemonics. So, the language that uses LD and ST is Instruction List.