The HD64180 is a Z80 -based embedded microprocessor developed by Hitachi with an integrated memory management unit (MMU) and on-chip peripherals. It appeared in 1985. The Hitachi HD64180 "Super Z80" was later licensed to Zilog and sold by them as the Z64180 and with some enhancements as the Zilog Z180 .
112-554: The HD64180 has the following features: The HD64180 has a pipelined execution unit which processes most instructions in fewer clock cycles than the Z80 . The most improved instruction group comprises the block instructions; for example those such as LDIR, CPIR, INIR and OTDR. This instruction type takes 21 transition states to execute per iteration; on the HD64180 it takes 14 t-states. The on-chip DMAC makes block memory transfers possible at
224-601: A MOS Technology 8502 . Zilog was later producing a low-power Z80 suitable for the growing laptop computer market of the early 1980s. Intel produced a CMOS 8085 (80C85) used in battery-powered portable computers, such as the Kyocera -designed laptop from April 1983, also sold by Tandy (as TRS-80 Model 100 ), Olivetti, and NEC. In following years, however, CMOS versions of the Z80 (from both Zilog and Japanese manufacturers) would dominate this market as well, in products such as
336-657: A 16-bit address register HL. In the 8080, this pairing was added to the BC and DE pairs as well, while HL was generalized to allow use as a 16-bit accumulator, not just an address register. The 8080 also introduced immediate 16-bit data for BC, DE, HL, and SP loads. Furthermore, direct 16-bit copying between HL and memory was now possible, using a direct address. The Z80 orthogonalized this further by making all 16-bit register pairs, including IX and IY, more general purpose, as well as allowing 16-bit copying directly to and from memory for all of these pairs. The 16-bit IX and IY registers in
448-476: A European second-source manufacturer SGS . The design was also copied by several Japanese, Eastern European and Soviet manufacturers. This won the Z80 acceptance in the world market since large companies like NEC , Toshiba , Sharp , and Hitachi started to manufacture the device (or their own Z80-compatible clones or designs). The Z80 continued to be used in embedded systems for decades after its introduction, with ongoing advancements. The latest addition to
560-474: A byte and two T-states for each occurrence. This naturally makes the index register unavailable for any other use, or else the need to constantly reload it would negate its efficiency. Fairchild Semiconductor Fairchild Semiconductor International, Inc. was an American semiconductor company based in San Jose, California . It was founded in 1957 as a division of Fairchild Camera and Instrument by
672-405: A copyright on their assembly mnemonics, a new assembly syntax had to be developed for the Z80. This time a more systematic approach was used: These principles made it straightforward to find names and forms for all new Z80 instructions, as well as orthogonalizations of old ones, such as LD BC,1234 . Apart from naming differences, and despite a certain discrepancy in basic register structure,
784-473: A day later, Faggin and Ungermann were kicking around ideas based on "integrated logic" when Ungermann said "how about Zilog?" Faggin immediately agreed, stating they could say it was the "last word in integrated logic". When they met the next day and both immediately recalled it, the company had its name. The first samples were returned from Mostek on March 9, 1976. By the end of the month, they had also completed an assembler -based development system . Some of
896-500: A high-level design, adding several concepts of his own. In particular, he used his experience on NEC minicomputers to add the concept of two sets of processor registers so they could quickly respond to interrupts . Ungerman began the development of a series of related controllers and peripheral chips that would complement the design. Through this period, Shima developed a legendary reputation for being able to convert logic concepts into physical design in realtime; while discussing
1008-466: A low-cost product like this would not be able to compete with a design from a company with its own production lines, like Intel. They then began considering a more complex microprocessor instead, initially known as the Super 80, with the main feature being its use of a +5 V bus instead of the more common −5, +5 and 12 V used by designs like the 8080. The new design was intended to be compatible with
1120-475: A lower cost and with greater performance and reliability, making other transistors obsolete. One such casualty was Philco 's transistor division, whose newly built $ 40 million plant to make their germanium PADT process transistors became nonviable. Within a few years, every other transistor company paralleled or licensed the Fairchild planar process. Hoerni's 2N1613 was a major success, with Fairchild licensing
1232-458: A method using only the 8080-model registers. The Z80 also introduced a new signed overflow flag and complemented the fairly simple 16-bit arithmetics of the 8080 with dedicated instructions for signed 16-bit arithmetics. The 8080-compatible registers AF, BC, DE, HL are duplicated as a separate register file in the Z80, where the processor can quickly (four t-states, the least possible execution time for any Z80 instruction) switch from one bank to
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#17327987032501344-480: A new CEO other than Noyce. In response, Noyce discreetly planned a new company with Gordon Moore , the head of R&D. They left Fairchild to found Intel in 1968 and were soon joined by Andrew Grove and Leslie L. Vadász , who took with them the revolutionary MOS Silicon Gate Technology (SGT), recently created in the Fairchild R&;D Laboratory by Federico Faggin who also designed the Fairchild 3708,
1456-460: A proposed feature, he would often interrupt and state how much room that would take on the chip and veto its addition if it was too large. The first pass at the design was complete by April 1975. Shima had completed a logic layout by the beginning of May. A second version of the logic design was issued on August 7 and the bus details by September 16. Tape-out was completed in November and converting
1568-527: A rate faster than the LDIR/LDDR instructions. The on-chip generator for wait states makes it possible to access too-slow hardware on a selective basis using a device filter, as is done for the TRS-80 Model 4 's balky keyboard. The on-chip ASCI makes it possible to implement additional RS-232 serial ports. The HD64180 will not execute the "undocumented" Z80 instructions, particularly the ones that access
1680-422: A regular encoding (common with the 8080) is that each of the 8-bit registers can be loaded from themselves (e.g. LD A,A ). This is effectively a NOP . New block transfer instructions can move up to 64 kilobytes from memory to memory or between memory and I/O peripheral ports. Block instructions LDIR and LDDR ( l oa d , i ncrement/ d ecrement, r epeat) use HL to point to the source address, DE to
1792-506: A relative address ( JR instead of JP ) using a signed 8-bit displacement. Only the zero and carry flags can be tested for these new two-byte JR instructions. (All 8080 jumps and calls, conditional or not, are three-byte instructions.) A two-byte instruction specialized for program looping is also new to the Z80: DJNZ ( d ecrement j ump if n on- z ero) takes a signed 8-bit displacement as an immediate operand. The B register
1904-566: A superfund. Superfund site cleanup ended in 1998. In 1997, the reconstituted Fairchild Semiconductor was reborn as an independent company, based in South Portland, Maine , with Kirk Pond as CEO. On March 11, 1997, National Semiconductor Corporation announced the US$ 550 million sale of a reconstituted Fairchild to the management of Fairchild with the backing of Sterling LLC, a unit of Citicorp Venture Capital. Fairchild carried with it what
2016-530: A system not using interrupts) it can be used as simply another 8-bit data register. The instructions LD A,R and LD A,I affect the Z80 flags register, unlike all the other LD (load) instructions. The Sign (bit 7) and Zero (bit 6) flags are set according to the data loaded from the Refresh or Interrupt source registers. For both instructions, the Parity/Overflow flag (bit 2) is set according to
2128-484: A team of Fairchild managers in preparation to defect to Plessey , a British company. Lamond had recruited Sporck to be his own boss. When negotiations with Plessey broke down over stock options, Lamond and Sporck succumbed to Widlar's and Talbert's (who were already employed at National Semiconductor) suggestion that they look to National Semiconductor. Widlar and Talbert had earlier left Fairchild to join Molectro, which
2240-453: A three-year term. On April 13, 2005, Fairchild announced appointment of Mark Thompson as CEO of the corporation. Thompson would also be President, Chief Executive Officer and a member of the board of directors of Fairchild Semiconductor International. He originally joined Fairchild as Executive Vice President, Manufacturing and Technology Group. On March 15, 2006, Fairchild Semiconductor announced that Kirk P. Pond would retire as Chairman at
2352-553: A total of $ 10 million for the entire industry being spent in all of 1975 (equivalent to $ 57 million in 2023). Someone from Exxon contacted the still-unnamed company, and arranged a meeting that eventually led to them providing an initial $ 500,000 funding in June 1975 (equivalent to $ 2.8 million in 2023). With funding being discussed, and a design to be built, Shima joined in February 1975. Shima immediately set about producing
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#17327987032502464-428: A variable base address (as in recursive stack frames ) and can also reduce code size by removing the need for multiple short instructions using non-indexed registers. However, although they may save speed in some contexts when compared to long/complex "equivalent" sequences of simpler operations, they incur a lot of additional CPU time (e.g., 19 T-states to access one indexed memory location vs. as little as 11 to access
2576-521: A week in order to meet the tight schedule given by the financial investors. The Z80 offered many improvements over the 8080: The Z80 took over from the 8080 and its offspring, the 8085 , in the processor market and became one of the most popular and widely used 8-bit CPUs. Some organizations such as British Telecom remained loyal to the 8085 for embedded applications, owing to their familiarity with it and to its on-chip serial interface and interrupt architecture. Likewise, Zenith Data Systems paired
2688-553: Is decremented, and if the result is nonzero, then program execution jumps relative to PC; the flags remain unaltered. To perform an equivalent loop on an 8080 requires separate DEC and conditional jump (to a two-byte absolute address) instructions (totalling four bytes), and the DEC alters the flag register. The index register (IX/IY, often abbreviated XY) instructions can be useful for accessing data organised in fixed heterogenous structures (such as records ) or at fixed offsets relative
2800-510: Is in context unless carefully commented. Thus it is advisable that exchange instructions be used directly and in short discrete code segments. The Zilog Z280 instruction set includes JAF and JAR instructions which jump to a destination address if the alternate registers are in context (thus officially recognizing this programming complication). As on the 8080, 8-bit registers are typically paired to provide 16-bit versions. The 8080 compatible registers are: The new registers introduced with
2912-591: Is often referred to as the "alternate register set" (by some, the "primed" register file since the apostrophe character is used to denote them in assembler source code and the Zilog documentation). This emphasizes that only one set is addressable at any time. However, the 8-bit accumulator A with its flag register F is bifurcated from the "general purpose" register pairs HL, DE and BC. This is accomplished with two separate instructions used to swap their accessibilities: EX AF,AF' exchanges only register pair AF with AF', while
3024-561: Is the ZX81 , which lets it keep track of character positions on the TV screen by triggering an interrupt at wrap around (by connecting INT to A6). The interrupt vector register , I , is used for the Z80 specific mode 2 interrupts (selected by the IM 2 instruction). It supplies the high byte of the base address for a 128-entry table of service routine addresses which are selected via an index sent to
3136-414: Is used as the byte counter. The Z80 can input and output any register to an I/O port using register C to designate the port. (The 8080 only performs I/O through the accumulator A, using a direct port address specified in the instruction; a self-modifying code technique is required to use a variable 8080 port address.) The last group of block instructions perform a CP compare operation between
3248-564: The EXX instruction exchanges the three general purpose register pairs HL, DE and BC with their alternates HL', DE' and BC'. Thus the accumulator A can interact independently with any of the general purpose 8-bit registers in the alternate (or primed) register file, or, if HL' contains a pointer to memory, some byte there (DE' and BC' can also transfer 8-bit data between memory and accumulator A). This can become confusing for programmers because after executing EX AF,AF' or EXX what were previously
3360-671: The 8008 8-bit microprocessor, Fairchild developed the Fairchild F8 8-bit microprocessor, which was according to the CPU Museum "in 1977 the F8 was the world's leading microprocessor in terms of CPU sales." In 1976, the company released the first video game system to use ROM cartridges, the Fairchild Video Entertainment System (or VES) later renamed Channel F , using the F8 microprocessor. The system
3472-729: The Amstrad NC100 , Cambridge Z88 and Tandy's own WP-2. Perhaps a key to the initial success of the Z80 was the built-in DRAM refresh, at least in markets such as CP/M and other office and home computers. (Most Z80 embedded systems use static RAM that do not need refresh.) It may also have been its minimalistic two-level interrupt system, or conversely, its general multi-level daisy-chain interrupt system useful in servicing multiple Z80 IO chips. These features allowed systems to be built with less support hardware and simpler circuit board layouts. However, others claim that its popularity
Hitachi HD64180 - Misplaced Pages Continue
3584-586: The CP/M operating system and Intel's PL/M compiler for 8080 (as well as its generated code), would run unmodified on the new Z80 CPU. Masatoshi Shima designed most of the microarchitecture as well as the gate and transistor levels of the Z80 CPU, assisted by a small number of engineers and layout people. CEO Federico Faggin was actually heavily involved in the chip layout work, together with two dedicated layout people. According to Faggin, he worked 80 hours
3696-678: The Game Boy and TI-83 series . The Z80 was the brainchild of Federico Faggin , a key figure behind the creation of the Intel 8080. After leaving Intel in 1974, Faggin co-founded Zilog with Ralph Ungermann . The Z80 was released in July 1976. With the revenue from the Z80, the company built its own chip factories . Zilog licensed the Z80 to the US-based Synertek and Mostek , which had helped them with initial production, as well as to
3808-454: The Intel 8080 , it offered a compelling alternative due to its better integration and increased performance. As well as the 8080's seven registers and flags register, the Z80 had an alternate register set that duplicated them, two 16-bit index registers and additional instructions including bit manipulation and block copy/search. Initially intended for use in embedded systems like the 8080,
3920-554: The TRS-80 Model 4 also used it. On the Victor HC-90 and HC-95 MSX2 computer, the HD64B180 was used for its turbo mode next to the regular Z80. This computer hardware article is a stub . You can help Misplaced Pages by expanding it . Z80 The Zilog Z80 is an 8-bit microprocessor designed by Zilog that played an important role in the evolution of early computing. Launched in 1976 and software-compatible with
4032-418: The " traitorous eight " who defected from Shockley Semiconductor Laboratory . It became a pioneer in the manufacturing of transistors and of integrated circuits . Schlumberger bought the firm in 1979 and sold it to National Semiconductor in 1987; Fairchild was spun off as an independent company again in 1997. In September 2016, Fairchild was acquired by ON Semiconductor . The company had locations in
4144-625: The 'reproductive' labor of expressing Navajo culture, rather than merely for wages." This claim was based on the opinion that circuits of the electronic chips had a mere resemblance with the complex geometric patterns on the Navajo rugs. Paul Driscoll, the Shiprock plant manager, spoke of the "untapped wealth of natural characteristics of the Navajo...the inherent flexibility and dexterity of the Indians." Although highly successful during its operation,
4256-406: The 8080); the four remaining codes are used extensively as opcode prefixes : CB and ED enable extra instructions, and DD or FD select IX+d or IY+d respectively (in some cases without displacement d) in place of HL. This scheme gives the Z80 a large number of permutations of instructions and registers; Zilog categorizes these into 158 different "instruction types", 78 of which are the same as those of
4368-430: The 8080, as the Z80 sometimes indicates signed overflow where the 8080 would indicate parity, possibly causing the logic of some practical 8080 software to fail on the Z80. ) This new overflow flag is used for all new Z80-specific 16-bit operations ( ADC , SBC ) as well as for 8-bit arithmetic operations, while the 16-bit operations inherited from the 8080 ( ADD , INC , DEC ) do not affect it. Also, bit 1 of
4480-500: The 8080, but add many of the nice features of the Motorola 6800 , including index registers and improved interrupts . While still being set up, the industry newsletter Electronic News heard of them and published a story on the newly formed company. This attracted the attention of Exxon Enterprises, Exxon 's high-tech investment arm. At the time, in the midst of the recession, there was very little venture capital available, with
4592-676: The 8085 with the 16-bit Intel 8088 in its first MS-DOS computer, the Zenith Z-100 , despite having previous experience with its pioneering Z80-based Heathkit H89 and Zenith Z-89 products. However, other computers were made integrating the Z80 with other CPUs: the Radio Shack TRS-80 Model ;16 with a Motorola 68000 , the DEC Rainbow with an 8088, and the Commodore ;128 with
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4704-513: The CPU during an interrupt acknowledge cycle; this index is simply the low byte part of the pointer to the tabulated indirect address pointing to the service routine. The pointer identifies a particular peripheral chip or peripheral function or event, where the chips are normally connected in a so-called daisy chain for priority resolution. Like the refresh register, this register has also sometimes been used creatively; in interrupt modes 0 and 1 (or in
4816-465: The California sites once a year, even though the semiconductor division earned most of the profits of the company. Fairchild's president at that time, John Carter, had used all the profits to fund acquisitions of unprofitable ventures. Noyce's position on Fairchild's executive staff was consistently compromised by Sherman Fairchild's faction. Charles E. Sporck was Noyce's operations manager. Sporck
4928-499: The Fairchild Semiconductor division was started with plans to make silicon transistors at a time when germanium was still the most common material for semiconductor use. According to Sherman Fairchild, Noyce's impassioned presentation of his vision was the reason Sherman Fairchild had agreed to create the semiconductor division for the traitorous eight. Noyce advocated the use of silicon as substrate – since
5040-412: The Intel 8080 (allowing operation of all 8080 programs on a Z80). The Zilog documentation further groups instructions into the following categories (most from the 8080, others entirely new like the block and bit instructions, and others 8080 instructions with more versatile addressing modes, like the 16-bit loads, I/O, rotates/shifts and relative jumps): No explicit multiply instructions are available in
5152-468: The SGT for its memory development. Federico Faggin, frustrated, left Fairchild to join Intel in 1970 and design the first microprocessors using SGT. Among the investors of Intel were Hodgson and five of the founding members of Fairchild. Sherman Fairchild hired Lester Hogan , who was the head of Motorola semiconductor division. Hogan proceeded to hire another hundred managers from Motorola to entirely displace
5264-745: The United States at San Jose, California ; San Rafael, California ; South Portland, Maine ; West Jordan, Utah ; and Mountain Top, Pennsylvania . Outside the US, it operated locations in Australia ; Singapore ; Bucheon, South Korea ; Penang, Malaysia ; Suzhou, China ; and Cebu, Philippines , among others. In 1955, William Shockley founded Shockley Semiconductor Laboratory , funded by Beckman Instruments in Mountain View, California ; his plan
5376-656: The United States. Fairchild dominated the market in DTL, op-amps and mainframe computer custom circuits. In 1965, Fairchild opened a semiconductor assembly plant on the Navajo Nation in Shiprock, New Mexico. At its peak, the plant employed over a thousand Navajos, the majority of whom were women. In The Shiprock Dedication Commemorative Brochure released by the Fairchild company, the Diné (Navajo) women circuit makers were celebrated as "culture workers who produced circuits as part of
5488-461: The Z80 and 8086 syntax are virtually isomorphic for a large portion of instructions. Only quite superficial similarities (such as the word MOV, or the letter X, for extended register) exist between the 8080 and 8086 assembly languages, although 8080 programs can be translated to 8086 assembly language by translator programs . The Z80 uses 252 out of the available 256 codes as single byte opcodes ("root instruction" most of which are inherited from
5600-584: The Z80 are fairly conventional, ultimately based on the register structure of the Datapoint 2200 . The Z80 was designed as an extension of the Intel 8080, created by the same engineers, which in turn was an extension of the 8008 . The 8008 was basically a PMOS implementation of the TTL-based CPU of the Datapoint 2200. The 2200 design allowed 8-bit registers H and L (High and Low) to be paired into
5712-469: The Z80 are primarily intended as base address-registers, where a particular instruction supplies a constant offset that is added to the previous values, but they are also usable as 16-bit accumulators, among other things. A limitation is that all operand references involving IX or IY require an extra instruction prefix byte, adding at least four clock cycles over the timing of an instruction using HL instead; this sometimes makes using IX or IY less efficient than
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#17327987032505824-424: The Z80 are: The refresh register , R , increments each time the CPU fetches an opcode (or an opcode prefix, which internally executes like a 1-byte instruction) and has no simple relationship with program execution. This has sometimes been used to generate pseudorandom numbers in games, and also in software protection schemes. It has also been employed as a "hardware" counter in some designs; an example of this
5936-522: The Z80 family is the eZ80 , which was offered alongside successor chips. Zilog announced the discontinuation of the Z80 in April 2024 after nearly five decades of production. At Fairchild Semiconductor , and later at Intel , physicist and engineer Federico Faggin had been working on fundamental transistor and semiconductor manufacturing technology. He also developed the basic design methodology used for memories and microprocessors at Intel and led
6048-455: The Z80 support and peripheral ICs were under development at this point, and many of them were launched during the following year. Among them were the Z80 CTC (counter/timer), Z80 DMA (direct memory access), Z80 DART (dual asynchronous receiver–transmitter), Z80 SIO (synchronous communication controller), and Z80 PIO (parallel input/output). The Z80 was officially launched in July 1976. One of
6160-549: The Z80's combination of compatibility, affordability, and superior performance propelled it to widespread adoption in video game systems and home computers during the late 1970s and early 1980s, fueling the personal computing revolution. Products it was used in include the Osborne 1 , Radio Shack TRS-80 , ColecoVision , ZX Spectrum and the Pac-Man cabinet; in later years it remained used in portables, best known for use in
6272-470: The Z80. However, this would likely be erroneous code on the 8080, as DAA was defined for addition only on that processor. The Z80 has six new LD instructions that can load the DE, BC, and SP register pairs from memory, and load memory from these three register pairs—unlike the 8080. As on the 8080, load instructions do not affect the flags (except for the special-purpose I and R register loads). A result of
6384-593: The acquisition of Impala Linear Corporation, based in San Jose, California, for approximately $ 6 million in stock and cash. Impala brought with it expertise in designing analog power management semiconductors for hand-held devices like laptops, MP3 players, cell phones, portable test equipment and PDAs. On January 9, 2004, Fairchild Semiconductor CEO Kirk Pond was appointed as a Director of the Federal Reserve Bank of Boston, elected by member banks to serve
6496-464: The alternate (primed) registers are now the main registers, and vice versa. The only way for the programmer to tell which set(s) are in context (while "playing computer" while scrutinizing the assembler source text, or worse, poring over code with a debugger) is to trace where each register swap is made at each point in the program. Obviously if many jump and calls are made within these code segments it can quickly become difficult to tell which register file
6608-448: The analog integrated circuit market, having introduced the first IC operational amplifiers , or "op-amps", Bob Widlar 's μA702 (in 1964) and μA709. In 1968, Fairchild introduced David Fullagar's μA741, which became the most popular IC op amp of all time. By 1965, Fairchild's process improvements had brought low-cost manufacturing to the semiconductor industry – making Fairchild nearly the only profitable semiconductor manufacturer in
6720-450: The basis of CMOS technology today. In 1963, Chih-Tang Sah and Frank Wanlass built CMOS MOSFET logic. In 1963, Fairchild hired Robert Widlar to design analog operational amplifiers using Fairchild's process. Since Fairchild's processes were optimized for digital circuits, Widlar collaborated with process engineer Dave Talbert. The collaboration resulted in two revolutionary products – μA702 and μA709. Hence, Fairchild dominated
6832-456: The byte at (HL) and the accumulator A. Register pair DE is not used. The repeating versions CPIR and CPDR only terminate if BC goes to zero or a match is found. HL is left pointing to the byte after ( CPIR ) or before ( CPDR ) the matching byte. If no match is found the Z ;flag is reset. There are non-repeating versions CPI and CPD . Unlike the 8080, the Z80 can jump to
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#17327987032506944-469: The company's annual stockholders' meeting on May 3, 2006. Pond would continue as a member of the company’s board of directors. Mark Thompson (then CEO) became Chairman. On September 1, 2007, New Jersey–based RF semiconductor supplier Anadigics acquired Fairchild Semiconductor's RF design team, located in Tyngsboro, Massachusetts, for $ 2.4 million. In April 2011, Fairchild Semiconductor acquired TranSiC,
7056-502: The current state of the IFF2 flip-flop. Although the Z80 is generally considered an eight-bit CPU, it has a four-bit ALU , so calculations are done in two steps. The first Intel 8008 assembly language was based on a very simple (but systematic) syntax inherited from the Datapoint 2200 design. This original syntax was later transformed into a new, somewhat more traditional, assembly language form for this same original 8008 chip. At about
7168-520: The design across the industry. In 1960, Fairchild built a circuit with four transistors on a single wafer of silicon, thereby creating the first silicon integrated circuit ( Texas Instruments ' Jack Kilby had developed an integrated circuit made of germanium on September 12, 1958, and was awarded a U.S. patent , however Kilby's method was not scalable and the semiconductor industry adopted Fairchild's process to manufacture integrated circuits). The company grew from twelve to twelve thousand employees, and
7280-415: The design directly. Faggin thought this would mean they could never compete even if they set up their own lines, and the agreement fell through. He then turned to Mostek, who agreed to a term of exclusivity while Zilog got their lines set up, and were eventually given the second source agreement. After considering many names for the new company, and finding them so unmemorable they could not recall them even
7392-482: The design. Sometime later, Shima was told by an engineer within NEC that the traps had delayed their copying efforts by six months. The successful launch allowed Faggin and Ungermann to approach Exxon looking for funding to build their own fab. The company agreed, and Zilog built a production line very rapidly. This allowed them to capture about 60 to 70% of the total market for Z80 sales. With their own line running, Mostek
7504-571: The destination address, and BC as a byte counter. Bytes are copied from source to destination, the pointers are incremented or decremented, and the byte counter is decremented until BC reaches zero. Non-repeating versions LDI and LDD move a single byte and bump the pointers and byte counter, which if it becomes zero resets the P/V ;flag. Corresponding memory-to-I/O instructions INIR , INDR , OTIR , OTDR , INI , IND , OUTI and OUTD operate similarly, except that B, not BC,
7616-502: The digital integrated circuit market. Their first line of ICs was the "micrologic" resistor–transistor logic (RTL) line which was used in the Apollo Guidance Computer . It had the advantage of being extremely simple – each inverter consisted of just one transistor and two resistors. The logic family had many drawbacks that had made it marginal for commercial purposes, and not well suited for military applications:
7728-486: The first customers was a buyer who, unknown to Zilog, worked for NEC. At the time, the Japanese electronics companies were well known for taking US chip designs and producing them without a license. The Zilog team had worried about this, and Faggin had come up with the idea of adding transistors that would be subtly modified to operate differently than a visual inspection would suggest. Shima added six of these "traps" around
7840-513: The flags register (a spare bit on the 8080) is used as a flag N that indicates whether the last arithmetic instruction executed was a subtraction or addition. The Z80 version of the DAA instruction (decimal adjust accumulator for BCD arithmetic) checks the N ;flag and behaves accordingly, so a (hypothetical) subtraction followed later by DAA will yield a different result on an old 8080 than on
7952-486: The form of BTL memos before being published in 1957. At Shockley Semiconductor , Shockley had circulated the preprint of their article in December 1956 to all his senior staff, including Jean Hoerni , who would later invent the planar process in 1959 while at Fairchild Semiconductor. In 1948, Bardeen and Brattain patented at Bell Labs an insulated-gate transistor (IGFET) with an inversion layer, this concept forms
8064-566: The formerly independent sections under the direction of Les Vadasz, further diluting the microprocessor's place in the company. That year, the 1973–1975 recession reached a peak and Intel laid off a number of employees. All of this led to Faggin becoming restless, and he invited Ungermann out for drinks and asked if he would be interested in starting their own company. Ungermann immediately agreed, and as he had less to do at Intel, left in August or September, followed by Faggin, whose last day at Intel
8176-521: The index registers IX and IY as 8-bit halves. The Hitachi CPU treats them as illegal instructions and accordingly executes the illegal instruction trap, redirecting the PC register to address zero. The Micromint SB180, SemiDisk Systems DT42 CP/M computers, and Olivetti CWP 1 and ETV 210s videotypewriters (also running ROM-based CP/M 2.2) were based on the Hitachi HD64180. The XLR8er upgrade board for
8288-427: The individual circuits. Noyce's invention was enabled by the planar process developed by Jean Hoerni. In turn, Hoerni's planar process was inspired by the surface passivation method developed at Bell Labs by Carl Frosch and Lincoln Derick in 1955 and 1957. At Bell Labs, the importance of Frosch and Derick technique and transistors was immediately realized. Results of their work circulated around Bell Labs in
8400-631: The introductory 2.5 MHz , via the well known 4 MHz (Z80A), up to 6 MHz (Z80B) and 8 MHz (Z80H). The NMOS version has been produced as a 10 MHz part since the late 1980s. CMOS versions were developed with specified upper frequency limits ranging from 4 MHz up to 20 MHz for the version sold today. The CMOS versions allowed low-power standby with internal state retained, having no lower frequency limit. The fully compatible derivatives HD64180 / Z180 and eZ80 are currently specified for up to 33 MHz and 50 MHz, respectively. The programming model and register set of
8512-472: The last of the original founders to leave, at which point the brain-drain of talents that had fueled the growth of the company was complete. A Fairchild advertisement of the time showed a collage of the logos of Silicon Valley with the annotation "We started it all". It was later, in 1971, Don Hoefler popularizated the name "Silicon Valley USA" in Electronic News . He notes he did not invent
8624-498: The logic could only tolerate about 100 millivolts of noise – far too low for comfort. It was awhile before Fairchild relied on more robust designs, such as diode–transistor logic (DTL) which had much better noise margins. Sales due to Fairchild semiconductor division had doubled each year and by the mid-1960s comprised two-thirds of total sales of the parent company. In 1966, Fairchild's sales were second to those of Texas Instruments , followed in third place by Motorola . Noyce
8736-414: The management of Fairchild. The loss of these iconic executives, coupled with Hogan's displacement of Fairchild managers demoralized Fairchild and prompted the entire exodus of employees to found new companies. Many of the original founders, otherwise known as the "fairchildren", had left Fairchild in the 1960s to form companies that grew to prominence in the 1970s. Robert Noyce and Gordon Moore were among
8848-498: The material costs would consist of sand and a few fine wires, the major cost would be in the manufacturing process. Noyce also expressed his belief that silicon semiconductors would herald the start of disposable appliances that, due to cheap electronic components, would not be repaired but merely discarded when worn out. Their first transistors were of the silicon mesa variety, innovative for their time, but exhibiting relatively poor reliability. Fairchild's first marketed transistor
8960-401: The name. See also Gregory Gromov and TechCrunch 2014 update of Hoefler's article. Hogan's action to hire from Motorola had Motorola file a lawsuit against Fairchild, which the court then decided in Fairchild's favor in 1973. Judge William Copple ruled that Fairchild's results were so unimpressive that it was impossible to assess damages "under any theory". Hogan was dismissed as president
9072-447: The next year, but remained as vice chairman. In 1973, Fairchild became the first company to produce a commercial charge-coupled device (CCD) following its invention at Bell Labs . Digital image sensors are still produced today at their descendant company, Fairchild Imaging. The CCD had a difficult birth, with the devastating effects on Fairchild of the 1973–75 recession that followed on the 1973 oil crisis . After Intel introduced
9184-436: The order by resigning abruptly. Furthermore, Fairchild's DTL technology was being overtaken by Texas Instruments's faster TTL (transistor–transistor logic). While Noyce was considered the natural successor to Carter, the board decided not to promote him. Sherman Fairchild led the board to choose Richard Hodgson. Within a few months Hodgson was replaced by a management committee led by Noyce, while Sherman Fairchild looked for
9296-426: The original Z80 (being 1 clock slower than in the 8080/8085); nonetheless, they are about twice as fast as performing the same calculations using 8-bit operations, and equally important, they reduce register usage. It was not uncommon for programmers to "poke" different offset displacement bytes (which were typically calculated dynamically) into indexed instructions; this is an example of self-modifying code , which
9408-407: The original Z80, though registers A and HL can be multiplied by powers of two with ADD A,A and ADD HL,HL instructions (similarly IX and IY also). Shift instructions can also multiply or divide by powers of two. Different sizes and variants of additions, shifts, and rotates have somewhat differing effects on flags because most of the flag-changing properties of the 8080 were copied. However,
9520-483: The other; a feature useful for speeding up responses to single-level, high-priority interrupts. A similar feature was present in the 2200, but was never implemented at Intel. The dual register-set is very useful in the embedded role, as it improves interrupt handling performance, but found widespread use in the personal computer role as an additional set of general registers for complex code like floating-point arithmetic or home computer games. The duplicate register file
9632-418: The parity flag bit P of the 8080 (bit 2) is called P/V (parity/overflow) in the Z80 as it serves the additional purpose of a twos complement overflow indicator, a feature lacking in the 8080. Arithmetic instructions on the Z80 set it to indicate overflow rather than parity, while bitwise instructions still use it as a parity flag. (This introduces a subtle incompatibility of the Z80 with code written for
9744-401: The plant was closed in 1975. While the Fairchild corporation claims the Diné women were chosen to work in the Shiprock plant due to their "'nimble fingers'" as previously noted, the women of the Shiprock reservation were actually chosen as the workforce due to a lack of labor rights asserted by the women in addition to "cheap, plentiful workers and tax benefits". Fairchild had not done well in
9856-535: The same memory using HL and INC to point to the next). Thus, for simple or linear accesses of data, use of IX and IY tend to be slower and occupy more memory. Still, they may be useful in cases where the "main" registers are all occupied, by removing the need to save/restore registers. Their officially undocumented 8-bit halves (see below) can be especially useful in this context, for they incur less slowdown than their 16-bit parents. Similarly, instructions for 16-bit additions are not particularly fast (11 clocks) in
9968-517: The same time, the new assembly language was also extended to accommodate the additional addressing modes in the more advanced Intel 8080 chip (the 8008 and 8080 shared a language subset without being binary compatible ; however, the 8008 was binary compatible with the Datapoint 2200). In this process, the mnemonic L , for LOAD , was replaced by various abbreviations of the words LOAD , STORE and MOVE , intermixed with other symbolic letters. The mnemonic letter M , for memory (referenced by HL),
10080-413: The semiconductor manufacturing industry, nor did it include Schlumberger Palo Alto Research. In the early 1980s, Fairchild was one of several silicon valley tech companies involved in a lawsuit brought on by residents of San Jose, California. The case pertained to industrial solvent contamination of ground water and soil in San Jose's Los Paseos neighborhood. A settlement was reached and the area designated
10192-438: The tape into a production mask required two more months. Faggin had already started looking for a production partner. By this time, Synertek and Mostek had both set up the depletion-mode production lines that could be used to produce the design. Having talked to Synertek previously, Faggin approached them first. However, the president of Synertek demanded that the company be given a second source license, allowing them to sell
10304-409: The value should be used as a memory address (as mentioned below), while the 8086 syntax uses brackets instead of ordinary parentheses for this purpose. Both Z80 and 8086 use the + sign to indicate that a constant is added to a base register to form an address. Note that the 8086 is not a complete superset of the Z80. BX is the only 8086 register pair that can be used as a pointer. Because Intel claimed
10416-478: The work on the Intel 4004 , the Intel 8080 and several other ICs. Masatoshi Shima was the principal logic and transistor-level designer of the 4004 and the 8080 under Faggin's supervision, while Ralph Ungermann was in charge of custom integrated circuit design. In early 1974, Intel viewed their microprocessors not so much as products to be sold on their own but as a way to sell more of their main products, static RAM and ROM . A reorganization placed many of
10528-478: The world, both operating since 1960. On March 19, 2001, Fairchild Semiconductor announced that it had completed the acquisition of Intersil Corporation 's discrete power business for approximately $ 338 million in cash. The acquisition moved Fairchild into position as the second-largest power MOSFET supplier in the world, representing a 20 percent share of this $ 3 billion market that grew 40 percent last year. On September 6, 2001, Fairchild Semiconductor announced
10640-434: The world’s first commercial MOS integrated circuit using SGT. Fairchild MOS Division was slow in understanding the potential of the SGT which promised not only faster, more reliable, and denser circuits, but also new device types that could enlarge the field of solid state electronics – for example, CCDs for image sensors, dynamic RAMs, and non-volatile memory devices such as EPROM and flash memories. Intel took advantage of
10752-407: Was Halloween 1974. When Shima heard, he asked to come to the new company as well, but having no actual product design or money, they told him to wait. The newly formed and unnamed company initially began designing a single-chip microcontroller called the 2001. They met with Synertek to discuss fabrication on their lines, and when Faggin began to understand the costs involved it became clear that
10864-521: Was being operated at a loss, and the bottomline subsisted mostly from licensing of its patents. In 1979, Fairchild Camera and Instrument was purchased by Schlumberger Limited , an oil field services company, for $ 425 million. At this time, Fairchild's intellectual properties, on which Fairchild had been subsisting, were expiring. In 1980, under Schlumberger management, the Fairchild Laboratory for Artificial Intelligence Research (FLAIR)
10976-454: Was due to the duplicated registers that allowed fast context switches or more efficient processing of things like floating-point math compared to 8-bit CPUs with fewer registers. (The Z80 can keep several such numbers internally, using HL'HL, DE'DE and BC'BC as 32-bits registers, avoiding having to access them from slower RAM during computation.) For the original NMOS design, the specified upper clock-frequency limit increased successively from
11088-529: Was effective as a recruiter, he was less effective as a manager. A core group of Shockley employees, later known as the traitorous eight , became unhappy with his management of the company. The eight men were Julius Blank , Victor Grinich , Jean Hoerni , Eugene Kleiner , Jay Last , Gordon Moore , Robert Noyce , and Sheldon Roberts . Looking for funding on their own project, they turned to Sherman Fairchild 's Fairchild Camera and Instrument , an Eastern U.S. company with considerable military contracts. In 1957
11200-487: Was finalized in April 1999 for $ 450 million. To this day, Fairchild remains an important supplier for Samsung. In August 1999, Fairchild Semiconductor again became a publicly traded company on the New York Stock Exchange with the ticker symbol FCS. Fairchild's South Portland, Maine, and Mountaintop, Pennsylvania, locations are the longest continuously operating semiconductor manufacturing facilities in
11312-460: Was given the go-ahead to start sales of their own versions, the MK3880, which provided a second-source for customers which Intel lacked. At the time, a second-source was considered extremely important as a start-up like Zilog might go out of business and leave potential customers stranded. Faggin designed the instruction set to be binary compatible with the 8080 so that most 8080 code, notably
11424-478: Was later acquired by National Semiconductor. In the fall of 1967, Fairchild suffered a loss for the first time since 1958 and announced write-offs of $ 4 million due to excess capacity, which contributed to a total loss of $ 7.6 million. Profits had sunk to $ 0.50 a share, compared to $ 3 a share the previous year, while the value of the stock dropped in half. In October 1967, the board ordered Carter to sell off all of Fairchild's unprofitable ventures. Carter responded to
11536-546: Was lifted out from within the instruction mnemonic to become a syntactically freestanding operand , while registers and combinations of registers became very inconsistently denoted; either by abbreviated operands (MVI D, LXI H and so on), within the instruction mnemonic itself (LDA, LHLD and so on), or both at the same time (LDAX B, STAX D and so on). Illustration of four syntaxes, using samples of equivalent, or (for 8086) very similar, load and store instructions. The Z80 syntax uses parentheses around an expression to indicate that
11648-590: Was mostly the Standard Products group previously segregated by Gil Amelio . The Fairchild Semiconductor Corporation announced November 27, 1997, that it would acquire the semiconductor division of the Raytheon Corporation for about $ 120 million in cash. The acquisition was completed on December 31, 1997. In December 1998, Fairchild announced the acquisition of Samsung 's power division, which made power MOSFETs , IGBTs , etc. The deal
11760-531: Was regular practice on nearly all early 8-bit processors with non- pipelined execution units. The index registers have a parallel instruction to JP (HL) , which is JP (XY) . This is often seen in stack-oriented languages like Forth , which at the end of every Forth word (atomic subroutines comprising the language) must jump unconditionally back to their thread interpreter routines. Typically this jump instruction appears many hundreds of times in an application, and using JP (XY) rather than JP THREAD saves
11872-526: Was reputed to run the tightest operation in the world. Sporck, Pierre Lamond and most managers had grown upset and disillusioned with corporate focus on unprofitable ventures at the expense of the semiconductor division. Executives at the semiconductor division were allotted substantially fewer stock options compared to other divisions. In March 1967, Sporck was hired away by Peter J. Sprague to National Semiconductor . Sporck brought with him four other Fairchild personnel. Actually, Lamond had previously assembled
11984-489: Was rewarded with the position of corporate vice-president and hence became the de facto head of the semiconductor division. However, internal trouble at Fairchild began to surface with a drop in earnings in 1967. There was increasing competition from newer start-ups. The semiconductor division, situated in Mountain View and Palo Alto, California, was actually managed by executives from Syosset, New York , who visited
12096-445: Was soon making $ 130 million a year. Fairchild's Noyce and Texas Instrument's Kilby had independently invented the integrated circuit (IC) based on bipolar technology. In 1960, Noyce invented the planar integrated circuit. The industry preferred Fairchild's invention over Texas Instruments' because the transistors in planar ICs were interconnected by a thin film deposit, whereas Texas Instruments' invention required fine wires to connect
12208-728: Was started within Fairchild Research. In 1985 the lab was separated to form Schlumberger Palo Alto Research (SPAR). Fairchild research developed the Clipper architecture , a 32-bit RISC -like computer architecture, in the 1980s, resulting in the shipping of the C100 chip in 1986. The technology was later sold to Intergraph , its main customer. Schlumberger sold Fairchild to National Semiconductor in 1987 for $ 200 million. The sale did not include Fairchild's Test Division, which designed and produced automated test equipment (ATE) for
12320-477: Was successful initially, but quickly lost popularity when the Atari 2600 Video Computer System (or VCS) was released. By the end of the 1970s they had few new products in the pipeline, and increasingly turned to niche markets with their existing product line, notably "hardened" integrated circuits for military and space applications and isoplanar ECL products used in exotic applications like Cray Computers. Fairchild
12432-546: Was the 1958 2N697 , a mesa transistor developed by Moore, and it was a success. The first batch of 100 was sold to IBM for $ 150 apiece in order to build the computer for the B-70 bomber. More were sold to Autonetics to build the guidance system for the Minuteman ballistic missile. At the same time Jean Hoerni developed the planar process , which was a major improvement: planar transistors could be made more easily, at
12544-514: Was to develop a new type of "4-layer diode" that would work faster and have more uses than then-current transistors . At first he attempted to hire some of his former colleagues from Bell Labs , but none were willing to move to the West Coast or work with Shockley again at that time. Shockley then founded the core of the new company with what he considered the best and brightest graduates coming out of American engineering schools. While Shockley
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