A language that uses mnemonics instead of opcodes is "assembly language". Assembly language is any low-level language used in electronic computers, microprocessors, microcontrollers, or other programmable devices. In assembly language, mnemonics are used to replace the opcodes of machine instructions, and address symbols or labels are used to replace the addresses of instructions or operands.
The operating environment of this tutorial: Windows 7 system, Dell G3 computer.
Assembly language is a machine-oriented language that uses mnemonics instead of opcodes and address symbols instead of operands.
As a programming language, machine language has poor flexibility and poor readability. In order to alleviate the discomfort that machine language brings to software engineers, people have upgraded and improved machine language: Replace a specific instruction with some letters and words that are easy to understand and remember. Through this method, it is easy for people to read the completed program or understand the functions the program is performing. Bug fixing and operation and maintenance of existing programs have become easier and more convenient. This language is what we call assembly language. That is, the second generation computer language.
Assembly Language (Assembly Language) is any low-level language used for electronic computers, microprocessors, microcontrollers or other programmable devices, also known as symbolic language. In assembly language, mnemonics are used to replace the opcodes of machine instructions, and address symbols or labels are used to replace the addresses of instructions or operands. In different devices, assembly language corresponds to different machine language instruction sets, which are converted into machine instructions through the assembly process. There is a one-to-one correspondence between a specific assembly language and a specific machine language instruction set, and they are not directly portable between different platforms.
Compared with machine language, assembly language has higher machine relevance and is easier to remember and write, but at the same time it retains the high speed and efficiency of machine language. Assembly language is still a machine-oriented language. It is difficult to understand the programming intention from its code. The designed program is not easy to be transplanted, so it is not as widely used as most other high-level computer languages. Therefore, today, when high-level languages are highly developed, they are usually used at the bottom level, usually for program optimization or hardware operations.
Disadvantages and advantages of assembly language
Assembly language is the fastest and most effective language that the computer provides to the user, and it is also the fastest and most effective language that can utilize all the functions of the computer. Hardware features and the only language that can directly control the hardware. However, because writing and debugging assembly language programs is more complicated than high-level languages, its application is currently not as widespread as high-level languages.
Assembly language is more readable than machine language, but compared with high-level languages, its readability is still poor. However, programs written using it have the characteristics of small storage space usage and fast execution speed, which cannot be replaced by high-level languages. In actual applications, whether to use assembly language depends on specific application requirements, development time and quality.
Advantages
As a second-generation programming language above machine language, assembly language also has many advantages:
You can easily read the memory status and hardware I/O interface status
The code you write can be executed accurately because there are fewer compilation steps
As a low-level language, it is highly scalable
Disadvantages
Because the code is very It is monotonous and has few special instruction characters, which makes the code lengthy and difficult to write.
Because assembly still requires you to call the memory to store data, it is easy for BUG to occur, and it is difficult to debug. Not easy
Even if a program is completed, it will take a lot of time to maintain it later.
Because of the particularity of the machine, the defect of poor code compatibility is caused.
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