(1) The lowest-level instructions that directly control a microprocessor. A single machine-language instruction typically translates into several microcode instructions.
In modern PC microprocessors, the microcode is hardwired and can’t be modified. Some RISC designs go one step further by completely eliminating the microcode level so that machine instructions directly control the processor. At the other end of the spectrum, some mainframe and minicomputer architectures utilize programmable microcode. In this case, the microcode is stored in EEPROM, which can be modified. This is called microprogramming.
(2) Some people use microcode as a synonym of firmware.
The term microcomputer is generally synonymous with personal computer (PC), or a computer that depends on a microprocessor. Microcomputers are designed to be used by individuals, whether in the form of PCs, workstations or notebook computers. A microcomputer contains a central processing unit (CPU) on a microchip (the microprocessor), a memory system (typically read-only memory […]
A highly integrated chip that contains all the components comprising a controller. Typically this includes a CPU, RAM, some form of ROM, I/O ports, and timers. Unlike a general-purpose computer, which also includes all of these components, a microcontroller is designed for a very specific task — to control a particular system. As a result, […]
Developed by IBM and available in 1999, a microdrive is an extremely small hard disk that can fit in a CompactCard memory slot, enabling digital cameras designed to use CompactFlash memory cards to gain larger storage capabilities.
Also called a splitter or DSL filter, microfilter is a small device that plugs into the telephone cable that provides service on the premise. The microfilter, which is installed on-site by your provider, splits the telephone line into a normal RJ11 telephone line and an ADSL line which is then used by the ADSL modem […]
- microfloppy disk
)An old moniker for the small, 3.5-inch floppy disks. PCs support two types of microfloppies: double-density microfloppies hold 720K. high-density microfloppies can store 1.44MB (megabytes). For Macintosh computers, which have always used microfloppies, there are three sizes: Single-sided standard microfloppies hold 400K. Double-sided standard microfloppies hold 800 K. Double-sided, high-density microfloppies hold 1.44 megabytes.