MicroVAX 78032
The MicroVAX 78032 (otherwise known as the DC333) is a microprocessor developed and fabricated by Digital Equipment Corporation (DEC) that implemented a subset of the VAX instruction set architecture (ISA). The 78032 was used exclusively in DEC's VAX-based systems, starting with the MicroVAX II in 1985. When clocked at a frequency of 5 MHz, the 78032's integer performance is comparable to the VAX-11/780 superminicomputer, which was introduced on 25 October 1977.[1] The microprocessor could be paired with the MicroVAX 78132 floating point accelerator for improved floating point performance. The 78032 represented a number of firsts for DEC. It was DEC's first single-chip microprocessor implementation of the VAX ISA and DEC's first self-fabricated microprocessor. The MicroVAX 78032 is also notable as it was the first semiconductor device to be registered for protection under the Semiconductor Chip Protection Act of 1984.
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The MicroVAX 78032 contains 125,000 transistors on an 8.7 by 8.6 mm (74.82 mm2) die that was fabricated in DEC's ZMOS process, a 3.0 µm NMOS logic process with two layers of aluminum interconnect. The die is packaged in a 68-pin surface-mounted leaded chip carrier.
MicroVAX 78132
The MicroVAX 78132 (otherwise known as the DC337) is a floating-point coprocessor for the MicroVAX 78032 microprocessor. It interfaces to the MicroVAX 78032 via the DAL bus and a few control lines. The MicroVAX 78132 was responsible for executing 61 out of 70 floating-point instructions defined by the MicroVAX subset of the VAX ISA and accelerates nine integer instructions.
The MicroVAX 78132 has a 100 ns microcycle divided into four 25 ns clock phases which is generated by a 40 MHz input clock. It was composed of five "elements": a 67-bit fraction processor, a 13-bit exponent processor, a 1-bit sign processor, a microsequencer and a bus interface unit.
The MicroVAX 78132 contained 32,141 transistors on a die measuring 8.4 mm by 6.6 mm (55.44 mm2). It was fabricated in DEC's ZMOS process, a 3.0 µm NMOS process with two layers of aluminum interconnect; and is packaged in a 68-pin surface-mounted leaded chip carrier.[2]
Other vendors
An identical copy of the 78032 was manufactured 1989/90 in East Germany as the U80701.
Another clone of the 78032 was manufactured in the Soviet Union under the designation KL1807VM3 (Russian: КЛ1807ВМ3).[3]
References
- Dobberpuhl, Daniel W.; et al. (1986). "The MicroVAX 78032 Chip, A 32-Bit Microprocessor". Digital Technical Journal. Digital Equipment Corporation. 1 (2).
- Bidermann, William R.; et al. (1986). "The MicroVAX 78132 Floating Point Chip". Digital Technical Journal. Digital Equipment Corporation. 1 (2).
- "Soviet microprocessors, microcontrollers, FPU chips and their western analogs". CPU-world. Archived from the original on 5 April 2016. Retrieved 24 March 2016.
Further reading
- Wolrich, G. et al. (October 1984). "A high performance floating point coprocessor". IEEE Journal of Solid-State Circuits 19 (5): pp. 690–696.