Bitwise operations are operations used to perform manipulations on bit patterns or binary numbers, which include working with individual bits. This quick, simple action, directly supported by the processor, is used to manage values for comparisons and calculations.
Basis of Computing
The binary digital system uses only two digits - 0 and 1. Computers work in binary format, which means that they store data and perform calculations using only zeros and ones.
Although a single binary digit can be used to represent True (1) (true) or False (0) (false) in the logic, several binary digits can be used to store large numbers and perform complex functions. In fact, any number can be represented in binary format.
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The terms “bits” and “bytes” are often confused and even used interchangeably, because they sound the same and both are abbreviated by the letter “B”. However, if spelled correctly, bits are truncated in lowercase "b", and bytes are truncated in upper case - "B". It is important not to confuse these two terms, since any measurement in bytes contains eight times as many bits. For example, a small 4 KB text file contains 4,000 bytes or 32,000 bits.Typically, files, storage devices, and storage capacity are measured in bytes, and data transfer rates are measured in bits. For example, an SSD memory card can have a capacity of 240 GB, while downloading can be carried at a speed of 10 Mbps. In addition, bits are also used to describe processor architecture, such as a 32-bit or 64-bit processor.
Pascal bitwise operations
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When an interrupt is triggered, it usually sets a bit in the status register, so that one service procedure can determine the exact cause of the interrupt. Testing individual bits allows you to quickly decode an interrupt source.On many embedded systems, the total available RAM may be 64, 128, or 256 bytes. In this environment, a single byte is usually used to store several data elements and Boolean flags, and then bit operations are used to set and read them.