First make sure config.sys has
device=c:\dos\himem.sys
dos=high
But there absolutely must not be a V86-mode manager such as emm386.exe.
Then you can use assembly instructions to read and write 32-bit addresses, in the format segment:32-bit offset, for example
xor ax,ax
mov ds,ax
mov esi,100003h
mov eax,
The execution result is exactly the same as the data at 0FFFFh:13h, proving that what is being accessed is memory above 1M
device=c:\dos\himem.sys
dos=high
But there absolutely must not be a V86-mode manager such as emm386.exe.
Then you can use assembly instructions to read and write 32-bit addresses, in the format segment:32-bit offset, for example
xor ax,ax
mov ds,ax
mov esi,100003h
mov eax,
The execution result is exactly the same as the data at 0FFFFh:13h, proving that what is being accessed is memory above 1M
