Chapter 3 - Instructions Flashcards
the vocabulary of commands understood by a given architecture
Instruction set
The idea that instructions and data of many types can be stored in memory as numbers and thus be easy to change, leading to the stored-program computer
Stored-program concept
a command that moves data between memory and registers
Data transfer instruction
a value used to delineate the location of a specific data element within a memory array
Address
a requirement that data be aligned in memory on natural boundaries
Alignment restriction
a signed number representation where a leading 0 indicates a positive number and leading 1 indicates a negative number. The complement of a value is obtained by complementing each bit(0 to 1 or 1 to 0) and then adding one to the result
Twos complement
a notation that represents the most negative value by 10 000two and the most positive value by 01…11tw0 leaving an equal number of negatives and positives but ending up with zeros, on positive (00…00two) and one negative (11…11two). The term is also used to mean the inversion of every bit of pattern: 0 to 1 and 1 to 0.
Ones complement
a notation that represents the most negative value by 00… 000¬two and the most positive value by 11…11two with 0 typically having the value to 00two thereby biasing the number such that the number plus the bias has a non-negative representation.
Biased notation
a form of representation of an instruction composed of fields of binary numbers
Instruction format
binary representation used for communication within a computer system
Machine language
the field that denotes the operation and format of an instruction
Opcode
the second register source operand
Rm
Shamt
shift amount
the first register source operand
Rn
the register destination operand. It gets the result of the operation
Rd
