标题: Memory Wave: I Mapped My Mental Progress [打印本页] 作者: AmeeCollea 时间: 2025-9-5 23:46 标题: Memory Wave: I Mapped My Mental Progress
In DOS memory management, extended memory refers to memory above the primary megabyte (220 bytes) of tackle space in an IBM Pc or suitable with an 80286 or later processor. The time period is primarily used under the DOS and Windows working programs. DOS applications, working in actual mode or virtual x86 mode, cannot instantly entry this memory, but are in a position to do so by an application programming interface (API) known as the Prolonged Memory Specification (XMS). This API is applied by a driver (similar to HIMEM.SYS) or the working system kernel, which takes care of memory administration and copying memory between standard and extended memory, by quickly switching the processor into protected mode. On this context, the term "prolonged memory" might refer to both the whole of the extended memory or only the portion out there by way of this API. Extended memory will also be accessed directly by DOS programs operating in protected mode utilizing VCPI or DPMI, two (completely different and incompatible) methods of utilizing protected mode below DOS.
