Editing 4-bit computing (section)

== List of 4-bit processors ==
[[File:National Semiconductor MM5700CA D Microprocessor.jpg|thumb|upright|National Semiconductor MM5700CA/D [[bit-serial]] 4-bit microcontroller]]

* [[Intel 4004]] (first 4-bit microprocessor from 1971, though [[Four-Phase Systems]] AL1 from 1969 is older, discontinued 1981)
* [[Intel 4040]] (discontinued 1981)
* [[TMS 1000]] (the first high-volume commercial microcontroller, from 1974, after Intel 4004; now discontinued<!-- for sure, and when?-->)
* [[Atmel]] [[MARC4]] core<ref name="Atmel_MARC4_Image" /><ref name="Atmel_MARC4_Product" /> (discontinued because of <!--Reason for EOL: -->Low demand. "Last ship date: 7 March 2015"<ref name="Atmel_EOL" />)
* [[Samsung]] S3C7 (KS57 Series) 4-bit microcontrollers (RAM: 512 to 5264 nibbles, 6&nbsp;MHz clock)
* [[Toshiba]] [[TLCS-47]] series
* [[HP Saturn]]<!-- and [[HP Saturn+|Saturn+]] series --> <!-- The HP "Saturn+" is not a real microprocessor but instead a Saturn emulator running on an ARM microprocessor -->
* [[NEC]] [[μPD75X]]
* NEC [[μCOM-4]]
* NEC (now [[Renesas]]) μPD612xA (discontinued), μPD613x, [[μPD6x]]<ref name="RenesasPD67" /><ref name="Renesas_uPD6P9" /> and [[μPD1724x]]<ref name="Renesas_uPD17240" /> infrared remote control transmitter microcontrollers<ref name="Renesas_Remote" /><ref name="Necel_ROMless" />
* [[EM Microelectronic-Marin]] EM6600 family,<ref name="Cravotta" /> EM6580,<ref name="EM6580_1" /><ref name="EM6580_2" /> EM6682,<ref name="EM6682" /> etc.
* Epson [[S1C63]] family
* [[National Semiconductor]] "COPS I" and "COPS II" ("[[COP400]]") 4-bit microcontroller families<ref>{{cite web |url=http://www.cpushack.com/2014/09/27/national-semiconductor-the-cop-before-the-cops/ |title=National Semiconductor: The COP before the COPS |last=Culver |first=John |date=September 27, 2014 |website=www.cpushack.com |publisher=<!-- N/A --> |access-date=May 28, 2020 |quote=<!-- N/A -->}}</ref>
* [[National Semiconductor]] MAPS MM570X
* [[Sharp Electronics|Sharp]] SM590/SM591/SM595<ref name="Sharp_1990" />{{rp|26–34}}
* Sharp SM550/SM551/SM552<ref name="Sharp_1990" />{{rp|36–48}}
* Sharp SM578/SM579<ref name="Sharp_1990" />{{rp|49–64}}
* Sharp SM5E4<ref name="Sharp_1990" />{{rp|65–74}}
* Sharp LU5E4POP<ref name="Sharp_1990" />{{rp|75–82}}
* Sharp SM5J5/SM5J6<ref name="Sharp_1990" />{{rp|83–99}}
* Sharp SM530<ref name="Sharp_1990" />{{rp|100–109}}
* Sharp SM531<ref name="Sharp_1990" />{{rp|110–118}}
* Sharp SM500<ref name="Sharp_1990" />{{rp|119–127}} (ROM 1197×8 bit, RAM 40×4 bit, a divider and 56-segment LCD driver circuit)
* Sharp SM5K1<ref name="Sharp_1990" />{{rp|128–140}}
* Sharp SM4A<ref name="Sharp_1990" />{{rp|141–148}}
* Sharp SM510<ref name="Sharp_1990" />{{rp|149–158}} (ROM 2772×8 bit, RAM 128×4 bit, a divider and 132-segment LCD driver circuit)
* Sharp SM511/SM512<ref name="Sharp_1990" />{{rp|159–171}} (ROM 4032×8 bit, RAM 128/142×4 bit, a divider and 136/200-segment LCD driver circuit)
* Sharp SM563<ref name="Sharp_1990" />{{rp|172–186}}