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| | Protected mode - Wikipedia, the free encyclopedia |
 | | While software-mediated multitasking is certainly possible on systems running in real mode, the memory protection features of protected mode prevent an erroneous program from damaging the memory "owned" by another task or by the operating system kernel. | | | Protected mode has a number of new features designed to enhance multitasking and system stability, such as memory protection, a paging system, and hardware support for virtual memory. | | | In modern computers, this switch is usually one of the very first tasks performed by the operating system at boot time. |
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http://en.wikipedia.org/wiki/Protected_mode
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| | Real mode - Wikipedia, the free encyclopedia |
| | Real mode is characterized by a 20 bit segmented memory address space (meaning that only 1 MB of memory can be addressed), direct software access to BIOS routines and peripheral hardware, and no concept of memory protection or multitasking at the hardware level. | | | Windows 3.1 removed support for Real Mode, and was the first mainstream operating environment which required at least an 80286 processor (not counting Windows 2.0 which was not a mainstream product). | | | Almost all modern x86 operating systems (Linux, Windows 95 and later, OS/2, etc.) switch the CPU into protected mode at startup. |
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http://en.wikipedia.org/wiki/Real_Mode
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| | X86 assembly programming in real mode - Wikipedia, the free encyclopedia |
| | All modern x86 operating systems use protected mode; however, when the computer boots, it starts up in real mode, so the part of the operating system responsible for switching into protected mode must operate in the real mode environment. | | | x86 assembly programming in real mode is a type of assembly computer programming for the Intel x86 in real mode. | | | Perhaps the most popular use of this type of programming was writing DOS programs in the 1980s. |
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http://en.wikipedia.org/wiki/X86_assembly_programming_in_real_mode
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| | Chapter 2 - basic protected mode architecture |
| | Consequently, the basic protected mode environment is the same as it was on 386 computers. | | | Protected mode was introduced with the 80286 processor around 1990 (before the advent of the 80286 processor, computers ran exclusively in real mode). | | | Many drawbacks of real mode, most notably the fact that real mode programs can only access 1 MB of the computer's physical memory, motivated Intel to create a totally differant environment known as protected mode. |
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http://www.geocities.com/efeiveson2003/ch2
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| | Hexapedia - X86 |
| | With the notable exception of the Intel 80386SX, which was 32-bit yet only had 24-bit addressing (and a 16-bit data bus), it was all 32-bit - all the registers, instructions, I/O space and memory. | | | As it was in the 286, segment registers were used to index inside a segment table that described the division of memory. | | | In addition, Enhanced Mode supported paging, a mechanism which made it possible to use virtual memory. |
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http://www.hexafind.com/encyclopedia/x86
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| | kernel - real-time multitasking kernel, embedded realtime kernel |
| | The smx API is unchanged, except for the lack of far objects in 32fpm. | | | Often, projects are upgrading from 186 to 386-class processors simply to gain performance, not to gain increased memory. | | | smx86 is ideal for real-mode projects that may need to move to protected mode in the future, in order to obtain more address space, or for other reasons. |
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http://www.smxinfo.com/articles/smx86ver.htm
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| | ProtectedMode overview [deinmeister.de] |
| | The only difference to pure Real Mode is that these programs are only allowed to use the instructions available in Privilege Level 3. | | | The problem is that this realization can lock up easily even if only one program is buggy. | | | One can realize that the logical address consisting of the segment register (now called selector coz it selects a descriptor within the table) and the index has nothing to do with the physical address. |
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http://www.deinmeister.de/x86modes.htm
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| | Virtual 8086 Mode |
| | Microsoft Windows/286 was one of the first programs to make use of protected mode on the 80286, providing some degree of hardware-assisted memory management and inter-application protection. | | | A simple way is to allocate 256 bytes more than you need to, put the contents of the program 256 bytes from the start of the buffer, and run it from there. | | | While this was a great improvement over the unprotected 8086, giving programmers the ability to separate code, data and stack, to limit the lengths of segments, and to move segments around in memory transparently, it was clear that Intel didn't have backwards compatibility in mind with the new mode. |
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http://www.openbg.net/sto/os/xml/v86.xml
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| | Chapter 14 80386 Real-Address Mode |
| | However, the LIDT instruction can be used in real-address mode to change the base and limit values in the IDTR. | | | These interrupt identifiers should not already have been used by the 8086 software, because they are in the range reserved by Intel. | | | After an NMI is recognized on the 80386, the NMI interrupt is masked until an IRET instruction is executed. |
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http://library.n0i.net/hardware/intel80386/Chap14.html
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| | DPMI Specification |
| | If a protected mode program is using memory in the first megabyte of address space, it is a good idea to use this function to turn off automatic page locking for regions of memory that will not be touched at interrupt time. | | | It also defines a new interface via software interrupt 31h that protected mode programs use to allocate memory, modify descriptors, call real mode software, etc. Any operating system that currently supports virtual DOS sessions should be capable of supporting DPMI without affecting system security. | | | Protected mode hardware interrupt handlers will always be called even for interrupts that occur in real mode. |
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http://burks.bton.ac.uk/burks/pcinfo/progdocs/dpmispec.htm
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| | PCTechGuide - The PC Technology Guide |
| | "Real mode" refers to an operating mode of x86 chips that replicates the memory management used by 8086 or 8088 chips, characterised by an absence of memory management or memory protection features and limiting the processor to 1MB of memory. | | | What you need to do now is copy Gscdrom.sys and the associated unzipped driver files to a folder on your Windows 98 Startup Disk and edit its Config.sys and Autoexec.bat files. | | | If you're lucky, you'll have this either on a floppy disk or CD-ROM that came with your drive. |
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http://www.pctechguide.com/tutorials/Win98Install_Real.htm
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| | Protected Mode Basics |
| | According to Intel, each time the CPU loads a segment register in real mode, the base address is 16 times the segment value, while the access rights and size limit attributes are given fixed, "real-mode compatible" values. | | | In protected mode, memory segmentation is defined by a set of tables (called descriptor tables) and the segment registers contain pointers into these tables. | | | Within a few hours, I realized that the book I had purchased didn't have any usable examples, since the examples in the book were intended to be programmed in EPROM CHIPS. |
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http://x86.ddj.com/articles/pmbasics/tspec_a1_doc.htm
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| | 15. Accessing 4 Gigs of Memory in Real Mode |
| | In protected mode, the value in the segment register is used as an index into a descriptor table located in memory, and the base address and size (which may be as small as 4 KB, or as large as 4 GB) from the descriptor table are loaded into the descriptor cache. | | | If switching modes caused an immediate recalculation of the descriptor cache, the processor would attempt to read entry 1000h of the descriptor table immediately upon switching to protected mode. | | | When the processor changes modes, the contents of the processor's internal descriptor cache are not changed. |
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http://www.faqs.org/faqs/assembly-language/x86/general/part2/section-1.html
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| | Protected Mode tutorial |
| | This is the maximum amount of physical memory addressable by a CPU with a 32-bit address bus. | | | Protected mode allows programs to access more than 1 megabyte of physical memory, and protects against misuse of memory (i.e. | | | In particular, there was no easy way to access more than 1 megabyte of physical memory. |
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http://my.execpc.com/~geezer/os/pm.htm
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| | Real Mode |
| | All processors have this real mode available, and in fact the computer normally starts up in real mode. | | | The decisions made in these early days have carried forward until now, and in each new processor, care had to be taken to be able to put the processor in a mode that would be compatible with the original Intel 8088 chip. | | | Even within DOS now there are special programs available that will "extend" DOS to allow access to extended memory (over 1 MB) and faster 32-bit access. |
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http://www.pcguide.com/ref/cpu/arch/int/modesReal-c.html
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| | Computer Associates Security Advisor Center Glossary |
| | Joke programs are usually seen as programs that do no real damage but in some way attempt to raise the program user's concern for the contents of their computer. | | | Specialized hardware that standard BIOSes were not written to recognize and handle had to either include a BIOS extension on its adaptor card or provide device drivers allowing access to the device (or both) if they were to be used other than by proprietary software written to their hardware interface. | | | Many programs that are clearly designed to harass, annoy and spy on unsuspecting users who are fooled into running their server part (that is, programs that better fit the first expansion of this acronym) are referred to as 'remote administration tools' in an attempt (usually by their writers, resellers, agents, etc) to legitimize them. |
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http://www3.ca.com/virus/glossary.asp
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| | Segment Registers: Real mode vs. Protected mode |
| | When you are writing code that crosses mode boundaries, you should consider all possible segment register writes. | | | When the CPU switches from SMM to any other mode it reads the entire contents of the segment registers from that work area. | | | Immediately after you exit pmode the segment registers still have the selector and base values that were loaded when you fixed the limit and attribute values (as described above). |
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http://my.execpc.com/~geezer/johnfine/segments.htm
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| | MSN Encarta - Search Results - Real Mode |
| | Real Mode, in computer science, the native or default operating mode in IBM and other computers based on the Intel 80x86 family of microprocessors;... | | | How well did we match your search term? | | | Mode (mathematics), the number in a given set of numbers that appears most frequently. |
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http://encarta.msn.com/Real_Mode.html
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| | real mode - Glossary - CNET.com |
| | Real mode limits the processor to 1MB of memory and provides no memory management or memory protection features. | | | An operating mode of x86 chips that replicates the memory management used by 8086 or 8088 chips. | | | The phrase is often used to describe device drivers that operate in this mode. |
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http://www.cnet.com/Resources/Info/Glossary/Terms/realmode.html
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| | Real Mode vs. Protected Mode |
| | If your computer is in real mode, software communicates directly with the computer's ports and devices. | | | If you've been working with computers since the days of DOS, the difference between real mode and protected mode is easy to understand. | | | But if your computer life began after Windows took over, the difference might not be as clear, and you might not appreciate the importance of the distinction. |
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http://www.windowsitpro.com/Article/ArticleID/43596/43596.html
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| | Using Registry Editor in Real Mode |
| | Windows 95 includes a Registry Editor program (Regedit.exe) that runs in both the real-mode MS-DOS environment and in the protected-mode Windows environment. | | | When you need to modify the registry without starting Windows 95, use Registry Editor in real mode. | | | If the changes you make cause problems in Windows 95 or you want to revert to the registry before you made the changes, restart your computer, press the F8 key when you see the "Starting Windows 95" message, and then choose Safe Mode Command Prompt Only from the Startup menu. |
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http://support.microsoft.com/support/kb/articles/q131/3/52.asp
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| | Computer with virtual machine mode and multiple protection rings (EP0187603B1) |
| | It is desirable to have the computer preserve the most privileged protection ring for the real mode to allow an orderly transition and allocation of resources of the computer system among users in the virtual mode. | | | When an instruction is retrieved, the processor first performs a probe operation to determine whether it can access any required memory locations in response to its current privilege level, and then determines whether it is in a privilege level which allows it to process the instruction. | | | A computer system including a processor and memory, the processor having a virtual mode of operation in which it uses a virtual machine monitor which allows it to service a plurality of users contemporaneously in a multiplexed manner, and a non-virtual, or real, mode of operation. |
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http://www.delphion.com/details?pn=EP00187603B1
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| | The Basics:What is Real Mode? |
| | Indeed, the way that modern Windows makes older Real Mode programs work is by using "virtual 8086" machines that provide a separate execution environment - a virtual CPU. | | | As computers have evolved, 1MB of addressable memory has not been enough, so subsequent processors in the IA-32 family have changed to allow larger address spaces. | | | System Management Mode Addressing is only available when running in system management mode, and that in turn is enabled by asserting a signal on the appropriate pin for the IA-32 CPU (assuming your version supports System Management Mode, of course). |
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http://www.osronline.com/article.cfm?article=225
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| | Real mode |
| | When running in protected mode, the 80286, 80386, and 80486 processors are capable of multitasking and addressing much more than 1 MB of memory. | | | The 8086 processor uses a 20-bit address bus, and can address up to 1 MB of memory. | | | The mode that allows an 80286, 80386, or 80486 processor to emulate an 8086 processor and run as though it were an 8086 processor. |
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http://www.novell.com/documentation/nw42/cncptenu/data/haw91lkm.html
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| | DPMI16 Real-mode Callback example |
| | */ fp = (void (*) (void)) MK_FP(Seg, Off); printf("From a real mode program, I "); /* Calculate number of bytes from the getIP call to the IP that the real-mode callback should load when it returns to the child program. | | | */ struct FUNC30X_STRUCT { BYTE4 edi, esi, ebp, always_0, ebx, edx, ecx, eax; BYTE2 flags, es, ds, fs, gs, ip, cs, sp, ss; } regBuf; // This struct is used to access the real mode // code's registers. | | | // spawnl(P_WAIT, "CHILD.EXE", "CHILD.EXE", rSegStr, rOffStr, NULL); asm { /* Free real mode callback address. |
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http://community.borland.com/article/0,1410,16950,0.html
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| | Introduction to Protected-Mode |
| | Protected-mode allowed the 80286 to exploit its 24-bit address bus and thus access up to 16MB of physical memory. | | | The solution came in 1982 when Intel introduced its new processor : The 80286. | | | A 32-bit address bus replaced the old 24-bit bus of the 80286 giving the user a total of 4GB physical address space, a third operating mode dubbed Virtual-Mode was implemented to support execution of old 8086 code while still running in a protected-mode environment, and, last but not least, Paging support was added. |
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http://www.internals.com/articles/protmode/introduction.htm
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| | Overview of Real Mode Removal from Windows Millennium Edition |
| | In Microsoft Windows 98, the Autoexec.bat and Config.sys files are used to set global environment variables. | | | Windows Me solves this issue by migrating current environment variables during Setup and placing them in the registry under the following subkey: | | | When real mode is removed, another method is required to set global environment variables (PATH, SET=, and so on). |
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http://support.microsoft.com/support/kb/articles/Q269/5/24.ASP
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| | Real DOS-Mode Patch for Windows Millennium |
| | This patch will modify "IO.SYS", "COMMAND.COM" and "REGENV32.EXE" in order to unhide the Real DOS-Mode on Windows ME systems, resulting in a similar boot process to the one available in Windows 9x. | | | Did you ever wonder why Windows ME, which is based on the Windows 9x kernel, can't access Real DOS-Mode? | | | Well, it seems that Microsoft simply decided to hide this option in Windows ME, for some unknown reason... |
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http://www.geocities.com/mfd4life_2000
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| | Real mode |
| | A mode that enables Intel 286 and higher processor to take on the attributes of a lower 8086 or 8088 processor in order to run older software programs. | | | This mode offers a higher clock speed but still limits the processor to a minimum of 1MB of RAM. | | | Were you able to locate the answer to your questions? |
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http://www.computerhope.com/jargon/r/realmode.htm
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| | The Old Joel on Software Forum - Calling real mode FAR call from protected mode |
| | However by moving the parameter data to the real mode memory and set SP accordingly, you should get a usable stack frame. | | | The protected mode is Causeway 32Bit DOS-Extended environment. | | | Use GetMemDos to allocate a number of paragraphs you need; paragraphs are 16 byte chunks if memory serves correctly. |
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http://discuss.fogcreek.com/joelonsoftware?cmd=show&ixPost=131513
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| | Real mode |
| | The address space is limited to 1 MB of physical memory and uses memory segmentation scheme. | | | is the 16-bit, backwards-compatible mode of the Intel 80386 family. | | | In real mode all of the CPU's protection features are disabled, paging is not supported, and program addresses correspond to physical memory addresses. |
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http://www.cs.virginia.edu/~bah6f/nachos486/paper/node12.html
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| | OS-FAQ Wiki - Real Mode |
| | That mode is mainly for backward compatibility and provide very few help for the modern developer (no memory protection, only 1MB of adressable memory, no virtual memory support). | | | Glossary -- RealMode 16 bits Operating mode in which the x86 cpu runs when it boots. | | | Page Execution took real: 0.131, user: 0.100, sys: 0.010 seconds |
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http://www.mega-tokyo.com/osfaq2/index.php/RealMode?PHPSESSID=47bee7d53cd28b17536546697bd06461
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| | Depeche Mode - the real meaning of the name (it's not Fast Fashion) |
| | Where this error started is hard to establish and when music sites such as the All Music Guide still get it wrong (also used for Biographies on the now defunct CDNOW), it is easy to see why this error still perpetuates across hundreds of sites. | | | The confusion arises from someone remembering their high school French: the verb 'se dépêcher' means to hurry, which is probably where the 'fast' originates (thanks to Lawrence Koch for explaining the French translation and the source of the error). | | | It is a common mistake to assume that the name Depeche Mode is purely a translation from the French for 'fast fashion'. |
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http://www.eightyeightynine.com/music/depeche-mode.html
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| | The Leader in Real Estate Software and Web Sites a la mode |
| | The Leader in Real Estate Software and Web Sites | | | Finally, your office can do it all — forms, data gathering, marketing, office management and more — with one set of tools. | | | The XSites Network ties real estate professionals together with advanced transaction management and collaboration tools that power each phase of the real estate transaction. |
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http://www.alamode.com
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| | WarBirds Bulletin Board - EMC easy-real mode pilot poll |
| | THis is not a slight on EZ Mode players.. | | | I have not really flown in 2.77 for the best part of a year now. | | | On the question of who has the advantage - Real Mode have spins and blackouts, but do they have a performance advantage, (planes can turn better or fly faster or something), or is it all disadvantage? |
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http://bbs.warbirdsiii.com/showthread.php?s=16762c03f7287860eeb98334ac12ed8d&threadid=794
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| | Virtual CD Changer Project |
| | This page is the home for my real mode OBD-II software. | | | ScanTool.net's software won't run on my oddball Thinkpad 720 laptop. | | | -OR- Gravis GamePad Pro connected to the PC Gameport (in GrIP mode) |
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http://techworld.dyndns.org/obd
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| | Transition from Protected Mode to Real Mode |
| | In the process, we'll mention things you need to do outside the scope of the code presented here — these items are marked. | | | For example, if you load an IDT for use in PM, you must load a IDT for use in RM; if you load segment registers with PM selectors, you must load the same segment registers with RM segment values, etc. | | | This page attempts to deal with every element necessary to accomplish this mode switch. |
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http://www.sudleyplace.com/pmtorm.html
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| | Real Mode Options command |
| | Mark this option to display the detailed constellation drawings. | | | This group contains advanced settings for each real mode options. | | | Use these options to specify settings for photographs and special effects when displaying the real mode options Virtual Sky. |
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http://www.bisque.com/help/TheSkyV6/Real_Mode_Options_command.htm
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| | Supported Processors |
| | All x86 real, extended and protected mode processors or cores including: |
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http://www.devtools.com/pcpp/processors.htm
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| | Windows me - Dialup Networking with Windows 98/ME |
| | Windows Me offers DOS support through “protected mode” which, Microsoft claims This “no-DOS” is also supposed to mean that Windows Me boots more quickly | | | How to set up Power Management on Windows 2000 | | | The Automatic Updates feature replaces the Critical Update |
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http://advertising-sales.siteslinks.com/sil/advertising-sales-windows-me.htm
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