Answer It is both 8 bit processors in a 40 pin package but it is not pin compatible, it have almost the same functions but it is very difficult to compare the two because it is not the same family.
PIC comes under RISC architecture (Reduced Instruction Set computer)
8051 is CISC (complex instruction set computer)
PICs are exclusives of microchip and 8051 is produced by various companies like atmel, philips etc.
the programming is quite simpler in pic.
RAM AND ROM memories are lesser for pic.
8031 microcontroller does not have any ROM where 8051 has ROM of 4K...
for arm ADC is inbuilt in lpc2148 where as for micro controller it is placed externally
8051 is CISC and avr in RISC
8051 is an old microcontroller design. It has been updated and expanded into a family of microcontrollers manufactured by several companies. PIC is not a microcontroller, but is an extensive family of microcontrollers designed and manufactured by Microchip, Inc. Both are quite popular, and there are many other microcontrollers available.
architecture
This question is literally impossible to answer without knowing a specific part number (and manufacturer which is usually easy to determine because it is based off the part number). The 8051 was first used in the IBM type computer as the keyboard controller to send key presses to the CPU. It has since become an architecture that appears in a number of other places. There are several manufacturers that produce low cost and low power microcontrollers based upon the 8051 with other peripherals included in the same package. Because there are numerous 8051 controllers, there is no one standard for connecting them to power for each may design their controller to meet their own design guidelines. Older 8051 microcontrollers usually require a 5 V power supply. Newer 8051 microcontrollers are more likely to require a 3.3 V power supply. The only way to tell is to read the part number off the chip and look up the manufacturer's data sheets for that part number. Fortunately, most data sheets are online these days.
the 8051 microcontrroller is the name doesnt matter easy or not....but the maiin and imp diff between both is at89s51 represents the 8051 chip no....along with the name of company i.e atmel, so all n all both are same thing ...... 89c51 have RISC architecture and contains less no of opcodes which are easy for programming. so iti is preferred than 8051.
Intel
The difference is that those MCUs that start with 80 are romless, those with 87 use EPROM erasable by light
The instructions used by Atmel 89CXX and 89CXXXX are the same or subset of 8051 microcontrollers.Fully static operation,flash program memory,less pin count andprecision analog comparator ( in case of 89C20510)are some of the attractions in going for these microcontrollers. Due to many similar features in the architecture and instruction and instruction set as that of 8051, it becomes possible for the 8051 designer to directly start using 89CXX and 89C20XX microcontrollers without any more efforts in learning these microcontrollers.
8051 is an old microcontroller design. It has been updated and expanded into a family of microcontrollers manufactured by several companies. PIC is not a microcontroller, but is an extensive family of microcontrollers designed and manufactured by Microchip, Inc. Both are quite popular, and there are many other microcontrollers available.
crystal oscilators mostrly of 11.05.... or 12MHz are used with microcontrollers,
4
avr is high speed cmpar to 8051.in 8051 there are less number of instructions
8051 Microcontrollers were popular computer chips used in Intel computers throughout the eighties and nineties. Though technology has advanced beyond their common use, they can still often be found in engineering schools as tools used in introductory microcontroller classes.
internal and external memory
The 8051 is a microcontroller. It has the MCS-51 core by Intel and was designed for embedded systems in the 1980's. The name of the CMOS version is 80C51. Today the core is still used in microcontrollers from other companies like Atmel, e.g. AT89C51.
architecture
89s51 and 89s52 both are same version of 8051 microcontroller
ANSWER The Intel 8051 had integrated RAM, ROM, and various I/O functions. This is typical of microcontrollers. I forget the amounts, probably 4 kB of ROM and 64 bytes of RAM? Newer 8051-compatible microcontrollers have a wide variety of memory and integrated I/O options. (Useless information: the 8051 used 12 oscillator cycles per machine instruction cycle, due to the synchronous way it decoded the instructions, fetched the operands, and stored the results. Newer versions get semi-asynchronous and run the same operands in 4, 3, or even 1 cycle.)