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Re: how could i get the hexadecimal content in memory at address FFFF0000-FFFFFFF0?

Star Liu 写道:
I know from cpu manual that when machine starts, it executes
instruction at FFFFFFF0, and then execute some code at
FFFF0000-FFFFFFF0, i hope i can get these machine code directly from
my memory, any tool to help me display the hexadecimal or binary

FFFF:0000, Too many F.
That's a history story about DOS and CP/M times...
When CPU has been reset, it will back to real mode and set SS=FFFF IP=0000. Here has some code which is mapped from BIOS. Sometime when we take a reflush to BIOS, will see something called "BootBlock", and can not be modified. This is what it used for. Commonly, it will do something like check memory, test if disk is ok, decide which device is used to boot, blah blah blah. Finally, It will get a block(about 512 bytes) of code, load it to 0000:7c00, then jump into it. It is the code we call MBR. Then, Computer is booted.
If u wanna to get this code, try to read BIOS.

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