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Intel 8051 is an 8-bit MCU?

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1: I have read Intel referred to their 8051 MCU by MCS-51. Then, who really invented the term/name "8051"? For instance, medicines have generic name, usually assigned by IUPAC. e.g. Paracetamol is a generic name of a medicine made from the words para-acetylaminophenol (it is chemical name of Paracetamol) and Apirin, which is a adopted name, has generic chemical name acetylsalicylic acid.

2: Please have a look on the attachment. Why is 8051 MCU considered an 8-bit microcontroller? Does it have anything to with its registers but there are also registers in it which are can handle data of more than 8-bit?
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Ian Rogers

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Its a series... Long ago they started with the intel 4004 (4 bit) and then onto 8008 series processors ( byte processors )

Microcontrollers started I believe at 8035 then MCS-48 onto 8051..

Processors were numbered 8080 and on The 8080 was basically ripped from Zilog Z80 it had the same machine code..

The first PC contained an 8088.. the XT was released with the 8086 ( multiplexed bus )

So its a long running numbering system....

Jon Wilder

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The MCS in "MCS-51" stands for "Micro Computer Series" I believe. Intel used it to denote their embedded processor families.
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