MICROPROCESSOR AND MICROCONTROLLER

Detailed explanation-1: -The Special Function Register (SFR) is the upper area of addressable memory, from address 0x80 to 0xFF. This area of memory can’t be used for data or program storage, but is instead a series of memory-mapped ports and registers.

Detailed explanation-2: -Port 0 is called ‘true bidirectional port’ as it floats (tristated) when configured as input. Port-1, 2, 3 are called ‘quasi bidirectional port’. Port-0 Pin Structure Port-0 has 8 pins (P0. 0-P0.

Detailed explanation-3: -In the 8051, register A, B, DPTR, and PSW are a part of the group of registers commonly referred to as SFR (special function registers).