M68000 datasheet(13/189 Pages) FREESCALE

13 / 189 page

1- 2

M68000 8-/16-/32-BIT MICROPROCESSORS USER’S MANUAL

MOTOROLA

1.1

MC68000

The MC68000 is the first implementation of the M68000 16/-32 bit microprocessor

architecture. The MC68000 has a 16-bit data bus and 24-bit address bus while the full

architecture provides for 32-bit address and data buses. It is completely code-compatible

with the MC68008 8-bit data bus implementation of the M68000 and is upward code

compatible with the MC68010 virtual extensions and the MC68020 32-bit implementation

of the architecture. Any user-mode programs using the MC68000 instruction set will run

unchanged on the MC68008, MC68010, MC68020, MC68030, and MC68040. This is

possible because the user programming model is identical for all processors and the

instruction sets are proper subsets of the complete architecture.

1.2

MC68008

The MC68008 is a member of the M68000 family of advanced microprocessors. This

device allows the design of cost-effective systems using 8-bit data buses while providing

the benefits of a 32-bit microprocessor architecture. The performance of the MC68008 is

greater than any 8-bit microprocessor and superior to several 16-bit microprocessors.

The MC68008 is available as a 48-pin dual-in-line package (plastic or ceramic) and 52-pin

plastic leaded chip carrier. The additional four pins of the 52-pin package allow for

additional signals: A20, A21, BGACK, and IPL2. The 48-pin version supports a 20-bit

address that provides a 1-Mbyte address space; the 52-pin version supports a 22-bit

address that extends the address space to 4 Mbytes. The 48-pin MC68008 contains a

simple two-wire arbitration circuit; the 52-pin MC68008 contains a full three-wire MC68000

bus arbitration control. Both versions are designed to work with daisy-chained networks,

priority encoded networks, or a combination of these techniques.

A system implementation based on an 8-bit data bus reduces system cost in comparison

to 16-bit systems due to a more effective use of components and byte-wide memories and

peripherals. In addition, the nonmultiplexed address and data buses eliminate the need for

external demultiplexers, further simplifying the system.

The large nonsegmented linear address space of the MC68008 allows large modular

programs to be developed and executed efficiently. A large linear address space allows

program segment sizes to be determined by the application rather than forcing the

designer to adopt an arbitrary segment size without regard to the application's individual

requirements.

1.3

MC68010

The MC68010 utilizes VLSI technology and is a fully implemented 16-bit microprocessor

with 32-bit registers, a rich basic instruction set, and versatile addressing modes. The

vector base register (VBR) allows the vector table to be dynamically relocated

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

M68000 Datasheet(PDF) 13 Page - Freescale Semiconductor, Inc

M68000 Datasheet(HTML) 13 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL