MICROPROCESSOR AND MICROCONTROLLER

Detailed explanation-1: -The vast majority of PIC registers are 8-bit registers. In the PIC there is only one data type: 8-bit. The range goes from the MSB (most significant bit) D7 to the LSB leastsignificant bit) D0. With an 8-bit data type, any data larger than 8 bits must be broken into 8-bit chunks before it is processed.

Detailed explanation-2: -All the PIC18 instructions use eight bits to specify the data register operand. A data register (excluding WREG) is also called a file register. Only 256 different registers can be specified by eight bits.

Detailed explanation-3: -PIC micro chips are designed with a Harvard architecture, and are offered in various device families. The baseline and mid-range families use 8-bit wide data memory, and the high-end families use 16-bit data memory. The latest series, PIC32MZ, is a 32-bit MIPS-based microcontroller.

Detailed explanation-4: -The CPU is at the center of the diagram and consists of an 8-bit ALU, an 8-bit working accumulator register (WREG), and an 8 8 hardware multiplier. The higher byte and the lower byte of a multiplication are stored in two 8-bit registers called PRODH and PRODL respectively.

Detailed explanation-5: -The PIC status register contains five flags, or bits, that can be set my PIC operations. In general, all five bits are set by the addition, subtraction, increment, and decrement instructions. For subtraction, the carry bit is set as if the minuend is added to the twos complement of the subtrahend.