Which memory type is typically non-volatile and used for firmware storage in MCUs?

Which memory type is typically non-volatile and used for firmware storage in MCUs?

• A. RAM
• B. Cache
• C. EEPROM
• D. ROM

Answer: (D)

Firmware in microcontroller units needs non-volatile storage so it remains available after power is removed. ROM provides permanent, non-volatile storage that holds the program code used to boot and run the device, making it the natural home for firmware. RAM and cache are volatile and lose their contents when power is off, so they can’t store firmware. EEPROM is non-volatile but is typically used for small amounts of data or configuration because it has slower write speeds and limited endurance, not the main firmware. So ROM best fits the requirement of non-volatile firmware storage.

Firmware in microcontroller units needs non-volatile storage so it remains available after power is removed. ROM provides permanent, non-volatile storage that holds the program code used to boot and run the device, making it the natural home for firmware. RAM and cache are volatile and lose their contents when power is off, so they can’t store firmware. EEPROM is non-volatile but is typically used for small amounts of data or configuration because it has slower write speeds and limited endurance, not the main firmware. So ROM best fits the requirement of non-volatile firmware storage.