2.2(lecture)2.5-Representing Instructions in the Computer

all MIPS instructions are ___ bits long

32

instruction format

A form of representation of an instruction composed of fi elds of binary numbers. -the rectangle with decimal reps in it, seperated feilds

op

Basic operation of the instruction, traditionally called the opcode.

machine language

Binary representation used for communication within a computer system

When instructions need to be larger then 32 bits, as they often do, this leads us to the fi nal hardware design principle:

Good design demands good compromises.

Itype

Immediate op,rs,rt,constant or address used for immediate data transfer instructions

shamt:

Shift amount

rs

Th e fi rst register source operand

rd

Th e register destination operand. It gets the result of the operation.

rt

Th e second register source operand.

■ funct

Th is fi eld, oft en called the function code, selects the specifi c variant of the operation in the op fi eld.

Th e compromise chosen by the MIPS designers is to keep all instructions the same length, thereby requiring _____

diff erent kinds of instruction formats for diff erent kinds of instructions

the formats are distinguished by the values in the ____,each format is assigned a distinct set of values in the fi rst fi eld (op) so that the hardware knows whether to treat the last half of the instruction as three fi elds (R-type) or as a single fi eld (I-type)

fi rst fi eld

Instructions are kept in the computer as a series of _____ electronic signals and may be represented as numbers

high and low

each piece of an instruction can be considered as an individual number, and placing these numbers side by side forms the ____.

instruction

What are the MIPS fields

op,rs,rt,rd,shamt,funct

A ____- occurs when an instruction needs longer fi elds than those shown above.

problem

R-type

register op,rs,rt,rd,shamt,funct

In MIPS assembly language, registers $s0 to $s7 map to____-

registers 16 to 23

In MIPS assembly language, registers $t0 to $t7 map onto

registers 8 to 15

machine code

sequence of machine langauge instruction