On Aug 28, 2013, at 6:39 PM, Rafael Machado <[email protected]> wrote:
> Hi everyone. > > I have a question that is probably simple for those who have more knowledge > about UEFI. > > Supose I have PXE boot DOS application that run on systems with the old bios > (not uefi systems). > My question is: > > Will this application still work in a system with no CSM and legacy support ? > No. And they don't run on Mac OS X, Linux, Android, iPhone, etc either. > As far as I know the answer is no, but I didn't find any documentation > telling why does this happen. And I need to find some document to explain to > some clients the changes and why the current application will not work in a > near future. > It is very difficult to document what does not work as that would require almost an infinite amount of documentation! > Any help ? > In the this case it is easy to explain. In UEFI (without CSM) there is no need to have a real mode IDT so there is typically nothing at address 0 (the protected mode/long mode IDT is usually not at zero). But even if the vector table existed there are no INT based BIOS 16-bit real mode services that are required by DOS to boot. Also BIOS/DOS imply magic hardware devices like 8259, VGA, PIT, etc and, these devices don't exist on all UEFI platforms. The Microsoft Surface RT would be an example of one of these platforms. Thanks, Andrew Fish > Thanks everyone. > Rafael R. Machado > ------------------------------------------------------------------------------ > Learn the latest--Visual Studio 2012, SharePoint 2013, SQL 2012, more! > Discover the easy way to master current and previous Microsoft technologies > and advance your career. Get an incredible 1,500+ hours of step-by-step > tutorial videos with LearnDevNow. Subscribe today and save! > http://pubads.g.doubleclick.net/gampad/clk?id=58040911&iu=/4140/ostg.clktrk_______________________________________________ > edk2-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/edk2-devel ------------------------------------------------------------------------------ Learn the latest--Visual Studio 2012, SharePoint 2013, SQL 2012, more! Discover the easy way to master current and previous Microsoft technologies and advance your career. Get an incredible 1,500+ hours of step-by-step tutorial videos with LearnDevNow. Subscribe today and save! http://pubads.g.doubleclick.net/gampad/clk?id=58040911&iu=/4140/ostg.clktrk _______________________________________________ edk2-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/edk2-devel
