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Answer:

In sequential order, one after another.


Machine Instructions

Instructions are normally executed in sequence. The program counter advances forward through memory one instruction at a time. Each time an instruction is executed, the next one is automatically selected for the next execution cycle.

Operations like "add two integers" and "compare two integers" are operations that a processor does in one machine cycle. Loops and branches require machine instructions that alter the normal sequence.

A machine instruction is a pattern of bits that directs the processor to perform one machine operation. Here is the machine instruction that directs the MIPS processor to add two 32-bit registers together (a register is a part of the processor that holds a bit pattern).

0000 0001 0010 1011 1000 0000 0010 0000

The instruction is 32 bits long. Each bit is 0 or 1. When bit patterns are displayed in a book they are usually shown in groups of four (as here). Of course, the spaces between groups are a convention of printing and are not actually part of the bit pattern.

Some of the bits in the instruction specify the operation (adding two registers), other bits specify which two registers to add. A few more bits say were to put the result.


QUESTION 5:

Inspect the instruction. Is it clear what the bits of the instruction mean?