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As an additional digression, I have heard that the ninth mode of Gregorian chant is a bit of a hack, in a good way, that is to say, a non-obvious capability discovered by later composers, but I am not sure about this.
However, from the sound of it, it reminds me of something on “IBM Compatible” to use a phrase I suspect none of you have read in a long time, PCs, with a 386 CPU or newer, called “Unreal Mode.” (No relation to the video game Unreal, at least as far as I am aware)
For those curious, this is a means of running the computer in Real Mode, the mode in which it boots to from the BIOS, which MS-DOS, its competitors such as DR-DOS, and the bootloaders for other operating systems on systems which still use a BIOS or emulated BIOS instead of uEFI firmware, in which you have unrestricted access to the hardware, albeit with a limitation in how much memory you can access (a very severe limitation, since one is limited to 16 bits worth, if I recall). Unreal mode kept the unrestricted access to the hardware, while enabling unrestricted access to 32 bit extended memory, which normally requires switching from the unprotected Real Mode in which MS DOS operates to Protected Mode, where a special piece of hardware on the CPU called an MMU, or Memory Management Unit, prevents, in theory (although this can be bypassed with various tricks of the sort that require us to periodically patch our operating systems) a user program from writing to the protected memory assigned to the operating system, or to other processes, which is normally a good thing as that provides protection from corruption, however, some classic DOS video games would use unreal mode as a hack to enable them to use all the memory that was installed and addressable without the added complexity and performance hit that would have occurred by switching to protected mode; DOS video games already were having to, in many cases, undertake functions that would now be handled by the operating system, but for some particularly brave developers, unreal mode was a useful tool around 1988-1994. I think the classic 2D science fiction dogfighter combat game Zone 66 uses it, which is also one reason why that game is notoriously finnicky and will typically not load if your DOS system has any extra drivers or bits of Windows loaded into memory as what are known as “TSRs” which is a type of horrible thing one had to do on CP/M, MS-DOS and other single-tasking operating systems, including i would assume the original MacOS, which had no multitasking abilitiy, to keep a program in memory but not executing.
This evolved into the cooperative multitasking of later MacOS versions from the late 1980s through to Mac OS/9, and also Windows through version 3.11; versions 95, 98 and ME have an idiosyncratic single user 32 bit pre-emptive multitasking kernel which, being single user, has no real security, and this was replaced by the NT-based multiuser versions of Windows, which were mainly used in businesses until Windows 2000 developed a following in the consumer space and Windows XP then replaced Windows 9x, aided by the very poor reliability of Windows ME, which also had compatibility problems that Windows 98 did not have, as a result of an unwise decision to try to stop using MS-DOS device drivers and software once Windows had booted, while leaving around a stripped-down version of DOS as a glorified bootloader and troubleshooting utility, a version of DOS that was highly incompatible with vintage games, et cetera. Also due to Microsoft being Microsoft, Windows 95-ME can only be booted by MS-DOS or the IBM branded PC-DOS, which is the same thing but with some extra IBM branding and bling, whereas Windows 3.1, 3.11 and earlier could be booted by DR-DOS, produced by Microsoft’s rival Digital Research, and can also be booted by the open source FreeDOS. DR-DOS is also used to bootload the Novell Netware operating system, which was once the dominant system for file sharing and user account management before Microsoft moved to dispose of them by adding that functionality to Windows itself.
So that’s more than I suppose most of you ever wanted to know about liturgics and operating system programming, but hey, that’s what I’m good at. Not much else, but when it comes to systems programming or developing systems software and management software for various somewhat exotic systems, that’s pretty much my balliwick. Well that, and lying around on my posterior dealing with the boredom of recuperation. I am very talented at that.
However, from the sound of it, it reminds me of something on “IBM Compatible” to use a phrase I suspect none of you have read in a long time, PCs, with a 386 CPU or newer, called “Unreal Mode.” (No relation to the video game Unreal, at least as far as I am aware)
For those curious, this is a means of running the computer in Real Mode, the mode in which it boots to from the BIOS, which MS-DOS, its competitors such as DR-DOS, and the bootloaders for other operating systems on systems which still use a BIOS or emulated BIOS instead of uEFI firmware, in which you have unrestricted access to the hardware, albeit with a limitation in how much memory you can access (a very severe limitation, since one is limited to 16 bits worth, if I recall). Unreal mode kept the unrestricted access to the hardware, while enabling unrestricted access to 32 bit extended memory, which normally requires switching from the unprotected Real Mode in which MS DOS operates to Protected Mode, where a special piece of hardware on the CPU called an MMU, or Memory Management Unit, prevents, in theory (although this can be bypassed with various tricks of the sort that require us to periodically patch our operating systems) a user program from writing to the protected memory assigned to the operating system, or to other processes, which is normally a good thing as that provides protection from corruption, however, some classic DOS video games would use unreal mode as a hack to enable them to use all the memory that was installed and addressable without the added complexity and performance hit that would have occurred by switching to protected mode; DOS video games already were having to, in many cases, undertake functions that would now be handled by the operating system, but for some particularly brave developers, unreal mode was a useful tool around 1988-1994. I think the classic 2D science fiction dogfighter combat game Zone 66 uses it, which is also one reason why that game is notoriously finnicky and will typically not load if your DOS system has any extra drivers or bits of Windows loaded into memory as what are known as “TSRs” which is a type of horrible thing one had to do on CP/M, MS-DOS and other single-tasking operating systems, including i would assume the original MacOS, which had no multitasking abilitiy, to keep a program in memory but not executing.
This evolved into the cooperative multitasking of later MacOS versions from the late 1980s through to Mac OS/9, and also Windows through version 3.11; versions 95, 98 and ME have an idiosyncratic single user 32 bit pre-emptive multitasking kernel which, being single user, has no real security, and this was replaced by the NT-based multiuser versions of Windows, which were mainly used in businesses until Windows 2000 developed a following in the consumer space and Windows XP then replaced Windows 9x, aided by the very poor reliability of Windows ME, which also had compatibility problems that Windows 98 did not have, as a result of an unwise decision to try to stop using MS-DOS device drivers and software once Windows had booted, while leaving around a stripped-down version of DOS as a glorified bootloader and troubleshooting utility, a version of DOS that was highly incompatible with vintage games, et cetera. Also due to Microsoft being Microsoft, Windows 95-ME can only be booted by MS-DOS or the IBM branded PC-DOS, which is the same thing but with some extra IBM branding and bling, whereas Windows 3.1, 3.11 and earlier could be booted by DR-DOS, produced by Microsoft’s rival Digital Research, and can also be booted by the open source FreeDOS. DR-DOS is also used to bootload the Novell Netware operating system, which was once the dominant system for file sharing and user account management before Microsoft moved to dispose of them by adding that functionality to Windows itself.
So that’s more than I suppose most of you ever wanted to know about liturgics and operating system programming, but hey, that’s what I’m good at. Not much else, but when it comes to systems programming or developing systems software and management software for various somewhat exotic systems, that’s pretty much my balliwick. Well that, and lying around on my posterior dealing with the boredom of recuperation. I am very talented at that.
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