Digital Logic and Microcomputers Flashcards

Which type of memory loses its contents when power is removed?

Answer: DRAM

DRAM (Dynamic Random Access Memory) is volatile — it loses all stored data when power is removed.

In a microprocessor system, what is the function of the address bus?

Answer: Specifies the memory or I/O location the CPU wants to access

The address bus is unidirectional and carries the binary address of the memory location or I/O device being accessed.

How many addressable memory locations can a microprocessor with a 16-bit address bus access?

Answer: 65,536

A 16-bit address bus can address 2¹⁶ = 65,536 unique memory locations.

What type of ROM can be erased using ultraviolet light and reprogrammed?

Answer: EPROM

EPROM (Erasable Programmable ROM) is erased by exposing it to ultraviolet light through a quartz window in the chip package.

In a microprocessor, what does the program counter (PC) register contain?

Answer: The address of the next instruction to be fetched

The program counter holds the memory address of the next instruction to be fetched and executed by the CPU.

What is the primary function of the arithmetic logic unit (ALU) in a microprocessor?

Answer: Perform arithmetic and logical operations on data

The ALU performs mathematical operations (add, subtract) and logical operations (AND, OR, NOT, XOR) on binary data.

Which memory type is both readable and writable during normal operation but retains data without power, used in USB drives and SSDs?

Answer: Flash memory

Flash memory is non-volatile, electrically erasable and rewritable, making it ideal for solid-state storage devices.