Right, the 386 has 10 internal segment descriptor caches but only 8 segment selector registers. The 286 had 8 and 6 respectively.
But wait, HIMEM.SYS used LOADALL to avoid going into protected mode and back?!? When you thought you knew everything (which I absolutely don't, but I knew it used big real mode on the 386 and I totally didn't expect LOADALL).
> More useful is the ability to load any arbitrary base address for the segment registers without entering protected mode. Some versions of Microsoft's HIMEM.SYS did this to copy data between real and extended memory.
But wait, HIMEM.SYS used LOADALL to avoid going into protected mode and back?!? When you thought you knew everything (which I absolutely don't, but I knew it used big real mode on the 386 and I totally didn't expect LOADALL).
> More useful is the ability to load any arbitrary base address for the segment registers without entering protected mode. Some versions of Microsoft's HIMEM.SYS did this to copy data between real and extended memory.
It is also explained at https://www.os2museum.com/wp/himem-sys-unreal-mode-and-loada...