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Home * Hardware * 68020

Die shot of Motorola 68020 [1]

The 68020 (MC68020) is a 32-bit microprocessor by Motorola, released in 1984 as successor of the 68000 and 68010. Amongst others, it was used in Apple Macintosh II personal computers, Sun-3 workstations, and advanced dedicated chess computers.

68020 has a 32-bit ALU, and like already the 68010 a "loop mode", considered a mini instruction cache. As further improvements, it has Coprocessor- and Multiprocessing support, an scaled indexing addressing mode with another level of indirection to many of the pre-existing modes, and some new instructions, 32×32→64 bits multiply and 64÷32→32 bits quotient and 32 bits remainder instructions, and bit field support, including a bit field find first one instruction (BFFFO), which actually performs an up to 32-bit Leading Zero Count [2].

See also


External Links


  1. Die shot of Motorola 68020 microprocessor (MC68020FE16E) by Pauli Rautakorpi, September 26, 2013, Wikimedia Commons
  2. Bit Field Instructions

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