Re: [tlug] Flash Memory History & BIOS Durability (or lack thereof)

[jep200404@example.com]

On Sun, 29 Apr 2012 11:30:11 +0900, Lyle H Saxon <llletters@example.com> wrote:

> I suspect those two old 486 Dynabook computers I had (which were made
> before flash memory was in production 

> So - before the
> advent of flash memory, no power meant meant no memory, didn't it?

No. 

There are several non-volatile memory[1] technologies that 
predate flash: mask ROM[2], PROM, EPROM[3], and EEPROM[4]. 
Flash is derived from EPROM. 

Almost all BIOSs are in non-volatile memory. Mask-ROM, EPROM, and 
flash are the commonly used non-voltile memories used for BIOSs. 
Everything uses flash now. Before flash, EPROM was dominant. 
A few manufacturers used mask ROM as Kalin wrote about. 
Mask ROM is forever. EPROM and flash forget over decades. 

[1] https://secure.wikimedia.org/wikipedia/en/wiki/Non-volatile_memory
[2] https://secure.wikimedia.org/wikipedia/en/wiki/Mask_ROM
[3] https://secure.wikimedia.org/wikipedia/en/wiki/EPROM
[4] https://secure.wikimedia.org/wikipedia/en/wiki/EEPROM