The KR580VM80A (russian: КР580ВМ80А) is a Soviet
microprocessor
A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...
, a
clone of the
Intel
Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 seri ...
8080
The Intel 8080 (''"eighty-eighty"'') is the second 8-bit microprocessor designed and manufactured by Intel. It first appeared in April 1974 and is an extended and enhanced variant of the earlier 8008 design, although without binary compatibili ...
CPU.
[ Different versions of this CPU were manufactured beginning in the late 1970s, the earliest known use being in the SM1800 computer in 1979. Initially called the K580IK80 (К580ИК80), it was produced in a 48-pin planar metal-ceramic package. Later, a version in a PDIP-40 package was produced and was named the KR580IK80A (КР580ИК80А). The pin layout of the latter completely matched that of Intel's 8080A CPU. In 1986 this CPU received a new part number to conform with the 1980 ]Soviet integrated circuit designation
Soviet integrated circuit designation is an industrial specification for encoding of names of integrated circuits manufactured in the Soviet Union and Post-Soviet Union countries. 25 years after the dissolution of the Soviet Union, a number of m ...
and became known as the KR580VM80A (КР580ВМ80А), the number it is most widely known by today (the KR580VV51A and KR580VV55A peripheral devices went through similar revisions). Normal clock frequency for the K580IK80A is 2 MHz, with speeds up to 2.5 MHz for the KR580VM80A. The KR580IK80A was manufactured in a 6 µm process. In the later KR580VM80A the feature size was reduced to 5 µm and the die became 20% smaller.
Technology and support chips
The KR580VM80A was manufactured with an n-MOS process. The pins were electrically compatible with TTL
TTL may refer to:
Photography
* Through-the-lens metering, a camera feature
* Zenit TTL, an SLR film camera named for its TTL metering capability
Technology
* Time to live, a computer data lifespan-limiting mechanism
* Transistor–transistor lo ...
logic levels. The load capacity of each output pin was sufficient for one TTL input. The output capacitance of each control and data pins was ≤ 100 pF each.
The family consists of the following chips:[
For brevity, the table above lists only the chip variants in a plastic DIP (prefix ''КР'') as well as the original planar package (prefix ''К''). Not listed separately are variants in a ceramic DIP (prefix ''КМ'' for commercial version and prefix ''М'' or no prefix for the military version) or export variants (prefix ''ЭКР'') in a plastic DIP but with a pin spacing of one tenth of an inch.
For the KR580VM1 (''КР580ВМ1'') see Further development below.
Several integrated circuits in the K580 series were actually intended for other microprocessor families: the KR580VR43 (''КР580ВР43'' — Intel 8243) for the K1816 family ( Intel MCS-48) and the KR580GF84 (''КР580ГФ84'' — ]Intel 8284
The Intel 8284 is a clock oscillator chip developed primarily for supplying clock signals for the Intel-8086/8087/8088/ 8089 series of processors. The commercial variant of the chip comes in 18-pin DIL and 20-pin PLCC packages, and originally w ...
) / KR580VG88 (''КР580ВГ88'' — Intel 8288
The Intel 8288 is a bus controller designed for Intel 8086/8087/8088/ 8089. The chip is supplied in 20-pin DIP package. The 8086 (and 8088) operate in maximum mode, so they are configured primarily for multiprocessor operation or for working wit ...
) / KR580VB89 (''КР580ВБ89'' — Intel 8289 The Intel 8289 is a Bus arbiter designed for Intel 8086/8087/ 8088/ 8089. The chip is supplied in 20-pin DIP package. The 8086 (and 8088) operate in maximum mode, so they are configured primarily for multiprocessor operation or for working with co ...
) for the K1810 family (Intel 8086
The 8086 (also called iAPX 86) is a 16-bit microprocessor chip designed by Intel between early 1976 and June 8, 1978, when it was released. The Intel 8088, released July 1, 1979, is a slightly modified chip with an external 8-bit data bus (allowi ...
). Additionally, most devices in the K580 series could be used for the K1810 series as well.
KR580VM80A vs. Intel 8080A
While the Soviet clone appears to be fully software-compatible with Intel 8080A, there is a slight difference between the two processors' interrupt handling logic, which looks like an error in the KR580VM80A's microcode. If a CALL instruction opcode is supplied during INTA cycle and the INT input remains asserted, the KR580VM80A does not clear its internal Interrupt Enable flag, despite the INTE output going inactive. As a result, the CPU enters a microcode loop, continuously acknowledging the interrupt and pushing the PC onto the stack, which leads to stack overflow. In a typical hardware configuration this phenomenon is masked by the behavior of 8259A interrupt controller, which deasserts INT during INTA cycle. The Romanian MMN8080 behaves the same as the KR580VM80A; no other 8080A clones seem to be affected by this error.
Applications
The KR580VM80A was popular in home computers, computer terminals, industrial controllers. Some of the examples of its successful application are:
* KUVT Korvet educational computer
* Radio-86RK
The Radio-86RK (russian: Радио-86РК) is a build-it-yourself home computer designed in the Soviet Union. It was featured in the popular ''Radio'' (russian: Радио) magazine for radio hams and electronics hobbyists in 1986. The letters R ...
(Радио 86РК), probably the most popular amateur single-board computer in the Soviet Union
* Micro-80
The Micro-80 (russian: Микро-80) was the first do-it-yourself home computer in the Soviet Union.
Overview
Schematics and information were published in the local DIY electronic magazine ''Radio'' in 1983. It was complex, using an KR580VM80A- ...
( Микро-80 in Russian), Radio 86RK's predecessor
* Orion-128 ( Орион-128 in Russian), Radio 86RK's successor, which had a graphical display
* Specialist (computer)
The Specialist (russian: Специалист) is a DIY computer designed in Soviet Union. Its description was published in ''Modelist-Konstructor'' (russian: Моделист-Конструктор), a magazine for scale model builders in 1987. I ...
, similar to Orion-128
* SM 1800 industrial mini computer
* Vector-06C
Vector-06C (russian: Вектор-06Ц) is a home computer with unique graphics capabilities that was designed and mass-produced in USSR in the late 1980s.
History
Vector-06C was created by Soviet engineers Donat Temirazov and Alexander Sokol ...
home computer, where KR580VM80A is overclocked to 3 MHz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...
by design
* TIA-MC-1
The TIA-MC-1 (russian: ТИА-МЦ-1) — Телевизионный Игровой Автомат Многокадровый Цветной (pronounced ''Televizionniy Igrovoi Automat Mnogokadrovyi Tcvetnoi''; meaning ''Video Game Machine – Mul ...
(ТИА-МЦ-1) arcade machine
* Juku E5101
Juku E5101 was a personal computer targeted at Estonian schools which was released in 1988. The computer had monochrome display, a mouse and basic LAN capabilities, it ran CP/M 2.2 based EKDOS and had a Soviet Intel 8080A clone KR580VM80A for CPU.< ...
educational computer designed in Estonia
* Maestro (Маэстро) soviet four voice hybrid analog synthesizer keyboard
Further development
Mirroring the development in the West, where the Intel 8080 was succeeded by the binary compatible
Binary-code compatibility (binary compatible or object-code-compatible) is a property of a computer system, meaning that it can run the same executable code, typically machine code for a general-purpose computer CPU, that another computer syste ...
Intel 8085
The Intel 8085 ("''eighty-eighty-five''") is an 8-bit microprocessor produced by Intel and introduced in March 1976. It is software-binary compatible with the more-famous Intel 8080 with only two minor instructions added to support its added in ...
and Zilog Z80
The Z80 is an 8-bit microprocessor introduced by Zilog as the startup company's first product. The Z80 was conceived by Federico Faggin in late 1974 and developed by him and his 11 employees starting in early 1975. The first working samples wer ...
as well as the source compatible Intel 8086
The 8086 (also called iAPX 86) is a 16-bit microprocessor chip designed by Intel between early 1976 and June 8, 1978, when it was released. The Intel 8088, released July 1, 1979, is a slightly modified chip with an external 8-bit data bus (allowi ...
, the Soviet Union produced the IM1821VM85A (''ИМ1821ВМ85А'', actually the CMOS version Intel 80C85), KR1858VM1 (''КР1858ВМ1''), and K1810VM86
The K1810VM86 (russian: К1810ВМ86, italic=yes) is a Soviet 16-bit microprocessor, a clone of the Intel 8086 CPU with which it is binary and pin compatible. It was developed between 1982 and 1985. The original K1810VM86 supported a clock frequen ...
(''К1810ВМ86''), respectively.[ The 580VM80 is still shown on the price list of 15 August 2022 of the "Kvazar" plant in Kyiv][ together with various support chips of the K580 series.
Another development, the KR580VM1 (''КР580ВМ1''), has no western equivalent.][ The KR580VM1 extends the Intel 8080 architecture and is binary compatible with it. The extensions differ, however, from both the Intel 8085 and the Zilog Z80. The KR580VM1 extends the address range from 64KB to 128KB. It adds two registers, H1 and L1, that can be used instead of H and L. Several 16-bit arithmetic instructions were added as well (DAD, DSUB, DCOMP).][ Just like the Intel 8085 and the Zilog Z80, the KR580VM1 needs only a single +5V power supply instead of the three voltages required by the KR580VM80A. The maximum clock frequency was increased from 2 MHz to 5 MHz while the power consumption was reduced from 1.35W to 0.5W, compared to the KR580VM80A.
]
See also
* Intel 8080
The Intel 8080 (''"eighty-eighty"'') is the second 8-bit microprocessor designed and manufactured by Intel. It first appeared in April 1974 and is an extended and enhanced variant of the earlier 8008 design, although without binary compatibil ...
* MCS-85 Family
* List of Soviet computer systems
This is the list of Soviet computer systems. The Russian abbreviation EVM (ЭВМ), present in some of the names below, means “electronic computing machine” (russian: электронная вычислительная машина).
List of ...
* Soviet integrated circuit designation
Soviet integrated circuit designation is an industrial specification for encoding of names of integrated circuits manufactured in the Soviet Union and Post-Soviet Union countries. 25 years after the dissolution of the Soviet Union, a number of m ...
References
External links
*
CPU World page about KR580VM80A
Reverse-engineering of KR580VM80A
{{List of Soviet microprocessors
Computer-related introductions in 1979
Computing in the Soviet Union
8-bit microprocessors