* 1954 – Silicon solar cells with 6 % efficiency made at Bell Laboratories

Current vendors of MCS-51 compatible processors include more than 20 independent manufacturers including Atmel, Infineon Technologies ( formerly Siemens AG ), Maxim Integrated Products ( via its Dallas Semiconductor subsidiary ), NXP ( formerly Philips Semiconductor ), Microchip Technology, Nuvoton ( formerly Winbond ), ST Microelectronics, Silicon Laboratories ( formerly Cygnal ), Texas Instruments, Ramtron International, Silicon Storage Technology, Cypress Semiconductor and Analog Devices.

* SLAB, the NASDAQ symbol for Silicon Laboratories

Other members of the consortium included Acer, Control Data Corporation, Kubota, NEC Corporation, NKK, Olivetti, Prime Computer, Pyramid Technology, Siemens, Silicon Graphics, Sony, Sumitomo, Tandem Computers, Wang Laboratories, and Zenith Data Systems.

* CAST, Inc. ( 8051 Silicon IP provider )

The 8051 microcontroller has two, a primary accumulator and a secondary accumulator, where the second is used by instructions only when multiplying ( MUL AB ) or dividing ( DIV AB ); the former splits the 16-bit result between the two 8-bit accumulators, whereas the latter stores the quotient on the primary accumulator A and the remainder in the secondary accumulator B.

Atmel introduced the first 8-bit flash microcontroller in 1993, based on the 8051 core.

The 8-bit Intel 8080 ( as well as the 8085 and 8051 ) microprocessor was basically a slightly extended accumulator-based design and therefore not orthogonal.

Their instruction sets vary from small 8-bit processors, such as the 8051 and PIC to 32-bit processors such as the ARM architectures or MIPS architectures.

Note that the use of " AVR " in this article generally refers to the 8-bit RISC line of Atmel AVR Microcontrollers.

The S-boxes accept 8-bit input and produce 32-bit output.

In the Alpha architecture, a byte was defined as an 8-bit datum, a word as a 16-bit datum, a longword as a 32-bit datum, a quadword as a 64-bit datum and an octaword as a 128-bit datum.

* There are two additional 8-bit accumulators, E and F. These can be concatenated to form a 16-bit accumulator called W. The existing 6809 16-bit accumulator, D, can also be concatenated with W to form a 32-bit accumulator Q.

This required either four matched 30-pin ( 8-bit ) SIMMs or one 72-pin ( 32-bit ) SIMM on a typical PC motherboard.

The IBM System / 360 has a 32-bit architecture with 16 general-purpose registers, but most of the System / 360 implementations actually use hardware that implemented a much simpler underlying microarchitecture ; for example, the System / 360 Model 30 had 8-bit data paths to the arithmetic logic unit ( ALU ) and main memory and implemented the general-purpose registers in a special unit of higher-speed core memory, and the System / 360 Model 40 had 8-bit data paths to the ALU and 16-bit data paths to main memory and also implemented the general-purpose registers in a special unit of higher-speed core memory.

:* The Model 50 had two internal datapaths which operated in parallel: a 32-bit datapath used for arithmetic operations, and an 8-bit data path used in some logical operations.

Most instructions have dot-letter suffixes, permitting operations to occur on 8-bit bytes (". b "), 16-bit words (". w "), and 32-bit longs (". l ").

Cost has plummeted over time, with the cheapest 8-bit microcontrollers being available for under $ 0. 25 in quantity ( thousands ) in 2009, and some 32-bit microcontrollers around $ 1 for similar quantities.

* Atmel AVR ( 8-bit ), AVR32 ( 32-bit ), and AT91SAM ( 32-bit )

* Freescale ColdFire ( 32-bit ) and S08 ( 8-bit )

* Microchip Technology PIC, ( 8-bit PIC16, PIC18, 16-bit dsPIC33 / PIC24 ), ( 32-bit PIC32 )

* NXP Semiconductors LPC1000, LPC2000, LPC3000, LPC4000 ( 32-bit ), LPC900, LPC700 ( 8-bit )

* Renesas RX, V850, Hitachi H8, Hitachi SuperH ( 32-bit ), M16C ( 16-bit ), RL78, R8C, 78K0 / 78K0R ( 8-bit )

* STMicroelectronics STM8 ( 8-bit ), ST10 ( 16-bit ) and STM32 ( 32-bit )

The Neo Geo was marketed as 24-bit, though it was technically a parallel processing 32-bit system with 24-bit addressing and a 16-bit data bus with an 8-bit Zilog Z80 as coprocessor.

The new instructions work on new data types: 64-bit packed vectors of either eight 8-bit integers, four 16-bit integers, two 32-bit integers, or one 64-bit integer.

* High-end digital image equipment are often able to deal with larger integer ranges for each primary color, such as 0 .. 1023 ( 10 bits ), 0 .. 65535 ( 16 bits ) or even larger, by extending the 24-bits ( three 8-bit values ) to 32-bit, 48-bit, or 64-bit units ( more or less independent from the particular computer's word size ).

The System / 360 used an 8-bit byte, 32-bit word, 64-bit double-word, and 4-bit nibble.

However, one of the main concepts of the MMX instruction set is the concept of packed data types, which means instead of using the whole register for a single 64-bit integer ( quadword ), one may use it to contain two 32-bit integers ( doubleword ), four 16-bit integers ( word ) or eight 8-bit integers ( byte ).

* Runs on 8-bit, 16-bit, and 32-bit CPUs.

Both AltiVec and SSE feature 128-bit vector registers that can represent sixteen 8-bit signed or unsigned chars, eight 16-bit signed or unsigned shorts, four 32-bit ints or four 32-bit floating point variables.

It is not at all uncommon, therefore, to see 4-or 8-bit microcontrollers used in modern applications, even though CPUs with much higher range ( such as 16, 32, 64, even 128-bit ) are available.

About 55 % of all CPUs sold in the world are 8-bit microcontrollers, over two billion of which were sold in 1997.

About 55 % of all CPUs sold in the world are 8-bit microcontrollers and microprocessors.

According to Semico, over four billion 8-bit microcontrollers were sold in 2006.

Many 8-bit CPUs or microcontrollers are the basis of today's ubiquitous embedded systems.

Zilog, Inc., previously known as ZiLOG ( which stands for " Z ( the last word of ) integrated logic "), is an American manufacturer of 8-bit and 16-bit microcontrollers, and is most famous for its Intel 8080-compatible Z80 series.

On February 19, 2009, Zilog announced that it had sold off their 8-bit Crimzon Universal Remote Control infrared microcontroller product line, as well as their ARM9 32-bit microcontrollers, including the Zatara security microcontrollers and 15 patents, to Maxim Integrated Products.

* Atmel AVR, family of 8-bit microcontrollers

H8 is the name of a large family of 8-bit, 16-bit and 32-bit microcontrollers made by Renesas Technology, originating in the early 1990s within Hitachi Semiconductor and still actively evolving as of 2006.

* v1: Intended to support migration from 8-bit microcontrollers, it is a cut-down version of the v2 processor-wise.

It is designed to easily replace the 8-bit Freescale 68HC08 microcontrollers and compete with low-end ARM chips.

The 6800 family of 8-bit microprocessors ( µPs ) and microcontrollers ( µCs ) is based upon the Motorola 6800 CPU.

* H8 Family, a 1990s large family of 8-bit and 16-bit microcontrollers made by Renesas Technology