Semiconductor & Computer Engineering
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{{Architecture sizes}} | {{Architecture sizes}} | ||
| − | The '''4-bit''' [[computer 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. | + | The '''4-bit''' [[computer 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 == | == Industry == | ||
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== Applications == | == Applications == | ||
| − | Most 4-bit [[microprocessor]]s were used almost exclusively in calculators and toys. | + | Most 4-bit [[microprocessor]]s were used almost exclusively in calculators and toys. 4 bits was a logical choice for many calculators that used [[binary coded decimal|BDC]] numbers representation. |
== 4-bit microprocessor == | == 4-bit microprocessor == | ||
Revision as of 22:46, 29 October 2015
The 4-bit computer 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.
Contents
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
- AMI 9209
- Fairchild PPS-25
- Hitachi HD35404
- HP Saturn (64-bit register, 4-bit data path)
- Intel 4004
- Intel 4040
- ITT 7151
- National IMP-4
- NEC μCOM 4
- NEC μCOM 41
- NEC µPD545
- Rockwell PPS-4/1
- Rockwell PPS-4/2
- TMS1000
- Toshiba T3472
- WD CR1872
4-bit microcontrollers
- AMI S2000
- Epson S1C63
- Fujitsu MB8840/1
- Hitachi HD404729S
- National COPS I (National MM5781/2)
- National COPS II
- National MM5799
- National MM57140
- National MM57152
- NEC μPD75X
- NEC µPD612X
- NEC µPD172XX
- MARC4
- Sanyo LM6402G
- Sanyo LC587004
- Sanyo LC587008
- Sanyo LC58E68
- Sharp SM552
- TLCS-47
4-bit discrete chips
- AMD Am2900, a family of 4-bit bit slice chips