R6000

The R6000, not to be confused with the IBM RAD6000, is a microprocessor chip set developed by MIPS Computer Systems that implemented the MIPS II instruction set architecture (ISA). The chip set consisted of the R6000 microprocessor, R6010 floating-point unit and R6020 system bus controller. The R6000 was the first implementation of the MIPS II ISA.

The R6000 was implemented with emitter-coupled logic (ECL). In the mid- to late 1980s, the trend was to implement high-end microprocessors with high-speed logic such as ECL. As MIPS was a fabless company, the R6000 chip set was fabricated by Bipolar Integrated Technology.

The R6000 had few users. Control Data Systems (CDS) used an 80 MHz version in their high-end 4680-300 Series InforServer server. MIPS used the R6000 in their RC6260 and RC6280 servers.

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