Editing Zilog Z80 (section)

{{Short description|8-bit microprocessor}}
{{Use mdy dates|date=May 2024}}
{{Infobox CPU
| name = Zilog Z80
| hide_subheadings = 
| image = Zilog Z80.jpg
| alt = A close-up of a silver computer chip with a gold square on a white background. The chip has text on it that says "ZILOG Z80 CPU DALLAS 7623".
| caption = A Z80 manufactured in June 1976
<!----------------- General Info ----------------->
| produced-start = July 1976
| produced-end = June 2024
| soldby = [[Zilog]]
| designfirm = [[Federico Faggin]], [[Masatoshi Shima]]
| manuf1 = Zilog, [[Mostek]], [[Synertek]], [[Società Generale Semiconduttori|SGS]], [[NEC]], [[Sharp Corporation|Sharp]], [[Toshiba]], [[Rohm]], [[GoldStar]], [[Hitachi]], [[National Semiconductor]],{{efn|Only in CMOS, National made no NMOS version, according to Oral History with Federico Faggin}} and others
| cpuid = <!-- CPUID or PVR value -->
| code = <!-- numerical identifier for the CPU (product code) -->
<!----------------- Performance ------------------>
| slowest =  2.5
| fastest = 8
| slow-unit = MHz
| fast-unit = MHz{{efn|CMOS variants went up to 20&nbsp;MHz and binary compatible derivatives went up to 50&nbsp;MHz}}
| fsb-slowest = <!-- Slowest FSB speed -->
| fsb-fastest = <!-- Fastest FSB speed -->
| fsb-slow-unit = <!-- Unit for slow speed. Default: MHz -->
| fsb-fast-unit = <!-- Unit for fast speed. Default: MHz -->
| hypertransport-slowest = <!-- Slowest HyperTransport speed -->
| hypertransport-fastest = <!-- Fastest HyperTransport speed -->
| hypertransport-slow-unit = <!-- Unit for slow speed. Default: GT/s -->
| hypertransport-fast-unit = <!-- Unit for fast speed. Default: GT/s -->
| qpi-slowest = <!-- Slowest QPI (QuickPath Interconnect) speed -->
| qpi-fastest = <!-- Fastest QPI speed -->
| qpi-slow-unit = <!-- Unit for slow speed. Default: GT/s -->
| qpi-fast-unit = <!-- Unit for fast speed. Default: GT/s -->
| dmi-slowest = <!-- Slowest DMI (Direct Media Interface) speed -->
| dmi-fastest = <!-- Fastest DMI speed -->
| dmi-slow-unit = <!-- Unit for slow speed. Default: GT/s -->
| dmi-fast-unit = <!-- Unit for fast speed. Default: GT/s -->
| data-width = 8 bits<ref name="Zilog 2005" />
| address-width = 16 bits<ref name="Zilog 2005" />
| virtual-width = <!-- Virtual address bus width in bits -->
<!-------------------- Cache --------------------->
| l1cache = <!-- Level 1 cache size -->
| l2cache = <!-- Level 2 cache size -->
| l3cache = <!-- Level 3 cache size -->
| l4cache = <!-- Level 4 cache size -->
| llcache = <!-- Last Level cache size -->
<!------- Architecture and classification -------->
| application = Embedded, desktop, handheld<!-- Handheld because it was used in the Game Boy and Game Gear devices. -->
| size-from = [[4&nbsp;μm process]]<!-- First fabrication size -->
| size-to = <!-- Second fabrication size -->
| microarch = <!-- Microarchitecture of the CPU -->
| arch = Z80{{efn|Backwards compatible with Intel 8080}}
| instructions = <!-- Instruction sets -->
| extensions = <!-- Extensions to the instructions -->
| numinstructions = <!-- Number of instructions -->
<!----------- Physical specifications ------------>
| transistors = 8,500
| numcores = <!-- Number of cores (2 for dual-core) -->
| amountmemory = <!-- Amount of system RAM for SoC or SiP -->
| gpu = <!-- Integrated GPU -->
| co-processor = <!-- A [[co-processor]](s) used together -->
| pack1 = 40-pin [[Dual in-line package|DIP]]
| pack2 = 44-pin [[Plastic leaded chip carrier|PLCC]]
| pack3 = 44-pin [[QFP]]
| sock1 = <!-- (1..9) Names of the sockets that the CPU was made for -->
<!--------- Products, models, variants ----------->
| core1 = <!-- (1..9) Names of the cores -->
| pcode1 = <!-- (1..9) Product code names -->
| model1 = <!-- (1..9) Model names -->
| brand1 = <!-- (1..9) Marketing names of the CPU -->
| variant = <!-- Variants in the same family and generation -->
<!------------------  History  ------------------->
| predecessor = [[Intel 8080]]
| successor = {{hlist | [[Zilog Z180|Z180]] | [[Zilog Z280|Z280]] | [[Zilog eZ80|eZ80]] }}
<!------------------  Support status ------------------->
| support status = <!-- Current support status -->
}}

The '''Zilog Z80''' is an [[8-bit computing|8-bit]] microprocessor designed by [[Zilog]] that played an important role in the evolution of early personal computing. Launched in 1976, it was designed to be [[Backward compatibility|software-compatible]] with the [[Intel 8080]], offering a compelling alternative due to its better [[Integrated circuit|integration]] and increased performance. Along with the 8080's seven [[Processor register|registers]] and flags register, the Z80 introduced an alternate register set, two 16-bit index registers, and additional instructions, including [[bit manipulation]] and block copy/search.

Originally intended for use in [[embedded system]]s like the 8080, the Z80's combination of compatibility, affordability, and superior performance led to widespread adoption in [[video game]] systems and [[home computer]]s throughout the late 1970s and early 1980s, helping to fuel the [[personal computing]] revolution. The Z80 was used in iconic products such as the [[Osborne 1]], [[TRS-80|Radio Shack TRS-80]], [[ColecoVision]], [[ZX Spectrum]], Sega's [[Master System]] and the ''[[Pac-Man]]'' arcade cabinet. In the early 1990s, it was used in portable devices, including the [[Game Gear]] and the [[TI-83 series]] of graphing calculators.<ref>{{Cite web |title=Chip Hall of Fame: Zilog Z80 Microprocessor - IEEE Spectrum |url=https://spectrum.ieee.org/chip-hall-of-fame-zilog-z80-microprocessor |access-date=2024-11-22 |website=spectrum.ieee.org |language=en}}</ref><ref>{{Cite web |last=Edwards |first=Benj |date=2024-04-22 |title=After 48 years, Zilog is killing the classic standalone Z80 microprocessor chip |url=https://arstechnica.com/gadgets/2024/04/after-48-years-zilog-is-killing-the-classic-standalone-z80-microprocessor-chip/ |access-date=2024-11-22 |website=Ars Technica |language=en-US}}</ref>

The Z80 was the brainchild of [[Federico Faggin]], a key figure behind the creation of the Intel 8080. After leaving Intel in 1974, he co-founded Zilog with [[Ralph Ungermann]]. The Z80 debuted in July 1976, and its success allowed Zilog to establish its own [[Semiconductor fabrication plant|chip factories]].{{sfn|Faggin|Shima|Ungermann|2007}} For initial production, Zilog licensed the Z80 to U.S.-based [[Synertek]] and [[Mostek]], along with European [[second-source]] manufacturer, [[Società Generale Semiconduttori|SGS]]. The [[Semiconductor intellectual property core|design]] was also copied by various Japanese, Eastern European, and Soviet manufacturers gaining global market acceptance as major companies like [[NEC]], [[Toshiba]], [[Sharp Corporation|Sharp]], and [[Hitachi]] produced their own versions or compatible clones.

Long after more advanced processors were introduced, the Z80 continued to be used in embedded systems, remaining in production until June 2024, nearly five decades after it began. Zilog also continued to enhance the basic design of the Z80 with several successors, including the [[Zilog Z180|Z180]], [[Zilog Z280|Z280]], and [[Zilog Z380|Z380]], with the latest iteration, the [[Zilog eZ80|eZ80]], introduced in 2001 and available for purchase {{as of|2025|lc=y}}.<ref name="discontinuation">{{Cite web |last=Edwards |first=Benj |date=April 22, 2024 |title=After 48 years, Zilog is killing the classic standalone Z80 microprocessor chip |url=https://arstechnica.com/gadgets/2024/04/after-48-years-zilog-is-killing-the-classic-standalone-z80-microprocessor-chip/ |access-date=May 23, 2024 |website=Ars Technica |language=en-us |archive-date=May 12, 2024 |archive-url=https://web.archive.org/web/20240512234211/https://arstechnica.com/gadgets/2024/04/after-48-years-zilog-is-killing-the-classic-standalone-z80-microprocessor-chip/ |url-status=live }}</ref>