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TI486 Microprocessor - Al Kossow's Bitsavers

TI486 Microprocessor - Al Kossow's Bitsavers

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<strong>Al</strong>tering SMM Code Limits<br />

COMMENT A<br />

now we are back to real mode with the limits set as desired<br />

A<br />

«user srni code»<br />

rsrn<br />

db<br />

db<br />

Ofh<br />

Oaah<br />

Setting other registers to the value of the CS register during the SMI<br />

COMMENT A<br />

load DS register with the same value as CS register. If our base is beyond 1<br />

MByte, we can't rely on the CS selector to be accurate so we need to use svdc<br />

and rsdc. svdc may be used on the CS segment to determine the base and limit.<br />

We need to set the segment type ourselves.<br />

A-46 <strong>TI486</strong> SMM Programmer's Guide

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