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Difference between revisions of "4-bit architecture"

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* {{itt|7150|ITT 7150}}
 
* {{national|COPS I|National COPS I}}
 
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Revision as of 22:13, 5 November 2015

Architecture word sizes
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The 4-bit architecture is a microprocessor architecture that has a datapath width or a highest operand width of 4 bits or a nibble. These architectures typically have a matching register file with registers width of 4 bits and 8-bit wide addresses.

Industry

Most of the first microprocessors during the early 1970s had 4-bit word length. Both the Intel4004 and the 4040 were 4-bits. The world's first single-chip microprocessor by Texas Instruments, the TMS1000, was also a 4-bit CPU. 4-bit word were proven to be very limiting and by 1974 there was a shift to larger architectures such as 8- and 12-bit architecture architectures.

Applications

Most 4-bit microprocessors were used almost exclusively in calculators and toys. 4 bits was a logical choice for many calculators that used BDC numbers representation.

4-bit microprocessor

4-bit microcontrollers