3 ms·
Isn't it actually the other way around? EEPROM (electronically-erasable programmable read-only memory) is limited in write cycles, requires a lot of preparation
by tremon 5y ago
Isn't it actually the other way around? EEPROM (electronically-erasable programmable read-only memory) is limited in write cycles, requires a lot of preparation to write, and is usually executed directly on the processor it's connected to. In comparison to EEPROM, flash memory is larger, can endure more write cycles and has a less complex ritual to write. Flash memory is used to store anything, even user data.
Then there's NVRAM (non-volatile random access memory), which is usually smaller than EEPROM but has infinite write cycles, requires very little preparation to write (since it's just RAM), and is often used to store configuration data, not code.
- mananaysiempre 5y agoYes, it doesn’t mesh well with historical usage of these terms, but that’s what (e.g.) AVR and STM8 manuals call it, so that’s what I’m used to. From what I understand “flash” (program memory) is NAND flash with ~ 10⁴ write cycles and larger erase blocks, connected to the instruction bus, and “EEPROM” is NOR flash with ~ 10⁵ write cycles and smaller erase blocks (sometimes single bytes), connected to the data bus or even accessed indirectly. > Then there's NVRAM I was under the impression that NVRAM is less of a specific technology and more of a desideratum. As for implementations of it aside from ages-old battery-backed RAM, there’s FRAM used in some TI microcontrollers and (Wikipedia tells me) some other stuff, but it’s all patented to hell and back so we’re unlikely to see any of it in general use (although TI microcontrollers are admittedly lovely).