Microcode

The microcode is the binary code of a microinstruction or a microinstruction sequence of a microprogram . The microcode can be seen as the “ machine language ” of the microprogram control unit for controlling the arithmetic and logic unit in a processor . In reality, some processors allow overwriting of the microcode defined during production and stored in a read-only memory (microprogram memory ) at the time of initialization . This is usually done by reloading a microcode stored in the BIOS . In this case, the reloaded microcode is retained until the processor is switched off; H. the micro-programming is reversible. A microcode update can be combined with a BIOS update. Under Linux the package contains the microcode for Intel processors, the package the microcode for AMD processors. intel-ucodelinux-firmware

The generation of microcode to control a virtual computing unit is conveyed in a didactic way with the microcode simulator MikroSim .

literature

• HP Gumm, M.Sommer: Introduction to Computer Science . 8th edition. Oldenbourg, 2009, ISBN 978-3-486-58724-1 .
• K. Wüst: Microprocessor technology: Fundamentals, architectures and programming of microprocessors, microcontrollers and signal processors . 3. Edition. Vieweg + Teubner Verlag, 2008, ISBN 978-3-8348-0461-7 .
• H. Bähring: Mikrorechner-Technik, Volume 1, Microprocessors and Digital Signal Processors . 3. Edition. Springer, 2002, ISBN 3-540-41648-X .
• H. Bähring: Microcomputer technology, Volume 2, buses, memories, peripherals and microcontrollers . 3. Edition. Springer, 2002, ISBN 3-540-43693-6 .
• Uwe Brinkschulte, Theo Ungerer: Microcontrollers and microprocessors . Springer, 2002, ISBN 3-540-43095-4 .

Individual evidence

1. ↑ ArchWiki: Microcode

Web links

• Microcode simulator MikroSim 2010 . 0/1 SimWare. Retrieved October 3, 2010.
• P6 Family Processor Microcode Update, Feature Review . J. Molina, W. Arbaugh. 2000. Retrieved October 3, 2010.
• A Brief History of Microprogramming . M. Smotherman. 2010. Retrieved October 3, 2010.
• Computer Structures: Principles and Examples, Part 2, REGIONS OF COMPUTER SPACE, Section 1, MICROPROGRAM-BASED PROCESSORS, page 151 ff . McGraw-Hill Computer Science Series. Retrieved October 3, 2010.
• Intel (R) 64 and IA-32 Architectures Software Developer's Manual, Volume 3A: System Programming Guide, Part 1, Chapter 9.11: "Microcode update facilities" . Intel Cooperation. December 2009. Retrieved October 3, 2010.
• Intel Microcode Update Utility . Retrieved September 30, 2012.
• A microcode reliability update is available that improves the reliability of systems that use Intel processors . Retrieved October 3, 2010.
• BIOS Update required when Missing Microcode message is seen during POST . Intel Cooperation. Retrieved October 3, 2010.