INTERSEGMENT CALL

                                          

An intersegment call, also known as an intersegment, jump or far jump, is a type of function call or jump instruction in computer programming. It is used to transfer program control from one segment of memory to another in segmented memory architectures.

In early computer systems, such as the x86 architecture, memory was divided into segments to overcome limitations of the 16-bit address space. Each segment had a base address and a limit, and addresses within a segment were specified as an offset from the base address. To access data or code in a different segment, an intersegment call or jump was used.

The intersegment call instruction typically involves specifying the target segment and the offset within that segment where the desired code or data resides. When the instruction is executed, the program control is transferred to the specified segment, and the code or data at the specified offset is executed or accessed.

Modern computer architectures, like x86-64, have moved away from segmented memory models and use a flat memory model, where the entire memory is addressed using a single linear address space. As a result, intersegment calls are less common in contemporary programming, but they may still be encountered in legacy systems or specialized programming scenarios.

It's worth noting that the specifics of intersegment calls can vary depending on the architecture and programming language being used. The details provided here are based on a general understanding of intersegment calls in segmented memory architectures.