3 ms·

does modern x86 even support real mode?

• niftich 9y ago
  Sure it does. All x86 CPUs boot up in real mode, for example. Bootloaders are written in real mode.
  • wolfgke 9y ago
    > Bootloaders are written in real mode. Not when the bootloader is an UEFI application. UEFI puts the processor into 32 bit protected mode or typically long mode (64 bit). So when your bootloader that is implemented as an UEFI application is started, you are already out of real mode.
• userbinator 9y ago
  AFAIK all x86 processors start in real mode. Intel tried making a 386 variant with only protected mode a long time ago, and it didn't sell very well: https://en.wikipedia.org/wiki/Intel_80376 https://en.wikipedia.org/wiki/Intel_80376
  • sebazzz 9y ago
    It might have a better chance these days, with UEFI becoming the default.
    • colejohnson66 9y ago
      Rumor is Intel is trying to get rid of the BIOS and just start the processor in protected mode
  • makomk 9y ago
    32-bit protected mode only, but with all support for paging and virtual memory removed? I can see why that combination never really caught on.
    • Crontab 9y ago
      They made it from 1989 to 2001 so it must have been okay for the embedded market that it targeted.