MICROPROCESSOR AND MICROCONTROLLER

Detailed explanation-1: -In all members of the 8051 family, the first 32 bytes of DATA memory (0x00-0x1F) is grouped into 4 banks of 8 registers each. Programs access these registers as R0-R7. The register bank is selected by two bits of the program status word, PSW.

Detailed explanation-2: -The 8051 contains two 16-bit registers: the program counter (PC) and the data pointer (DPTR). Each is used to hold the address of a byte in memory. Program instruction bytes are fetched from locations in memory that are addressed by the PC.

Detailed explanation-3: -With 8-bit data type, any data type larger than 8-bits must be broken into 8-bit chunks before it is processed. The most widely used registers of the 8051 are A (accumulator), B, R0-R7, DPTR (data pointer), and PC (program counter). All these registers are of 8-bits, except DPTR and PC.