Go Premium for a chance to win a PS4. Enter to Win

x
?
Solved

Accessing BIOS NVRAM ?

Posted on 2006-07-13
7
Medium Priority
?
894 Views
Last Modified: 2013-11-12
Does anyone know how to access BIOS NVRAM address space?
I believe it can be done in 'Ring 0' but I'm not sure how.
I want to be able to modify a few bytes using VB6 and TVicHW52 . I'm running WIN98se.

Any help greatly appreciated.
0
Comment
Question by:aztarac
  • 2
4 Comments
 

Author Comment

by:aztarac
ID: 17155787
I looked at that thread before I posted my question.

The 'accepted answer' does state that the way to write is not known.

The following Microsoft link for Bios writers may offer some clues...but I dont understand it:

>Writing to CMOS NVRAM
>BIOS code should write to CMOS NVRAM by generating a system management interrupt (SMI). AML code can generate a SMI by writing a specific value to the SMI command port. AML code can pass the CMOS offset and value to be written through the NVRAM memory operation region. The BIOS SMI handles the writes to CMOS, and also updates the memory area pointed by the CMRM operation region to reflect the correct CMOS contents.

Full text:
http://www.microsoft.com/whdc/system/pnppwr/powermgmt/BIOSAML.mspx

I'm still hoping for a solution:(

0
 
LVL 9

Accepted Solution

by:
Rob_Jeffrey earned 1000 total points
ID: 17156373
Right - missed that.  
Sorry - I simply skimmed over the body.

Unless you want to get into device driver (DDK) devekopment - it doesn't look easy.
The entire problem is - viruses.  Because some lousy people have written some pretty nasty things in the past there is a lot of hidden and proprietary information regarding the NVRAM these days.

What is it you are trying to do?  Perhaps we can come at it from another angle?
0
 
LVL 49

Assisted Solution

by:DanRollins
DanRollins earned 1000 total points
ID: 17330346
You may be able to install a device drive that will allow access to I/O ports.  Here's one:
    http://www.driverlinx.com/DownLoad/DlPortIO.htm

This article appears to be on point:
    Pop Open a Privileged Set of APIs with Windows NT Kernel Mode Drivers
    http://www.microsoft.com/msj/0398/driver.aspx

But I agree with Rob_Jeffrey:  If you describe your ultimate goal, it might be possible to find a way to avoid this low-level grunging.  Whenever there is a legitimate need for standard programs to access low-level resources, there is often an more direct way to do it.  So what's on your mind?

-- Dan
0

Featured Post

Free Tool: SSL Checker

Scans your site and returns information about your SSL implementation and certificate. Helpful for debugging and validating your SSL configuration.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

What is Waterfall Model? Waterfall model is the classic Software Development Life Cycle method practiced in software development process. As the name "waterfall" describes, this development is flowing downwards steadily like waterfall, i.e., procee…
Introduction Many of the most common information processing tasks require sorting data sets.  For example, you may want to find the largest or smallest value in a collection.  Or you may want to order the data set in numeric or alphabetical order. …
Is your data getting by on basic protection measures? In today’s climate of debilitating malware and ransomware—like WannaCry—that may not be enough. You need to establish more than basics, like a recovery plan that protects both data and endpoints.…
This lesson discusses how to use a Mainform + Subforms in Microsoft Access to find and enter data for payments on orders. The sample data comes from a custom shop that builds and sells movable storage structures that are delivered to your property. …

876 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question