Manapság (már 2008 óta) a Microchip forgalmazza az ATMEL által fejlesztett mikrovezérlőket, amik között vannak 8051-es magra épülők is. A Microchip honlapján kétféle családot különböztetnek meg: PIC (Microchip fejlesztések) és AVR (ATMEL fejlesztések). Nemes egyszerűséggel az AVR-ek közé veszik a 8051-es magra épülőket is, pedig azoknak semmi közük az AVR-ekhez.
Az első olyan mikrovezérlő, amiben a program tárolására flash memória szolgált, az ATMEL AT89C51 volt, ez 1993-ban jelent meg.
http://ww1.microchip.com/downloads/en/devicedoc/doc0265.pdf
The AT89C51 is normally shipped with the on-chip Flash
memory array in the erased state (that is, contents = FFH)
and ready to be programmed. The programming interface
accepts either a high-voltage (12-volt) or a low-voltage
(V CC ) program enable signal. The low-voltage program-
ming mode provides a convenient way to program the
AT89C51 inside the user’s system, while the high-voltage
programming mode is compatible with conventional third-
party Flash or EPROM programmers.
The AT89C51 is shipped with either the high-voltage or
low-voltage programming mode enabled.
https://www.datsi.fi.upm.es/docencia/Informatica_Industrial/DMC/atmel/s…
INTRODUCED AT89C51 IN MAY 1993
- BASED ON DATABASE RECEIVED FROM INTEL
https://ww1.microchip.com/downloads/en/DeviceDoc/doc2464.pdf
Atmel introduced the first 8-bit Flash microcontroller in 1993. This first-generation Flash
microcontroller is based on the industry-standard 8051 core, and uses a separate high
voltage supply for programming.Atmel’s second-generation of Flash microcontrollers were introduced in 1997. These
microcontrollers are based on the AVR ® architecture, and include In-System
Programmable and single-voltage Flash memory. As a result, no additional programming
voltages are needed. There are several additional benefits offered by this technology. It is
now possible to assemble the printed circuit board and program the microcontroller before
the software has received final approval. If a software bug is found, it is possible to
reprogram the microcontroller without removing it from the printed circuit board.
Az elsőként fejlesztett AVR mikrovezérlő az AT90S8515 volt még 1996-ban, viszont nem ez jelent meg elsőnek a piacon, hanem 1997-ben az AT90S1200.