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Not being a Poqet expert (just knowing a few things about DOS), it's a guess if this will work. The debug commands are (comments on what each line does to the right, don't need to type those): L 0100 1 0 1 ;load first sector of drive B: to 0100 E 0103 ;enter...

in the L (load) and W (write) command, the first number is the load address (0100), then second the drive (0=A: ), then the starting sector (0) and count (1). So you would have to change the second number to 1. That doesn't look right, it should normally be some ASCII text, not executable code...

After reading the boot sector (that's the "L" command), enter "D 0103 010A".

He formatted it in the HP 200 LX. Since it's a 2 MB card, it would likely have been as FAT12. But it's possible that the Poqet disk driver or DOS expects certain parameters, instead of reading the correct ones from the BPB. Might be this problem...

Windows XP might work, but in my experience, Win9x is the safer bet for SRAM cards - newer operating systems probably don't support them at all. And the reason why the Poquet can't access a 2 MB card formatted in the 200LX might be that it only supports one specific format, and the HP palmtop...

Have now tested it in QEMU, and of course it doesn't work with extended partitions. One of the system structures this code uses being named BDSM is only fitting :)

Well your suggestion has been helpful anyway, I found 5 files where my (DOS-based, written in assembly) conversion tool has eaten a line for some reason. It's the font data for GRAFTABL, nothing else was affected - I'm working on fixing them right now. edit: uploaded new zip file. "diff...

I don't have a GitHub account and no idea how any of this works. And I'm fine with someone else doing that, as I said the code should be the same as the original except for charset and line endings (which as far as I understand would appear in a diff as every line being changed...)

$EF $BF $BD is U+FFFD, which some editor or other tool configured for UTF-8 put in to replace what it considered invalid characters. This is the only string that needs to be replaced by a single character, and only in a few files, others aren't mangled. $C4, $B4 and $BF are the original line...

Notepad++ (not the same thing as the Notepad built into Windows) calls it OEM-US. https://npp-user-manual.org/docs/preferences/#encoding-menu

Try setting the encoding to Western European -> OEM-US or OEM-850

By the way, the same Alt+Numpad codes probably still work in Windows 10 (I know they do in Win7). It translates the DOS character codes to Unicode codepoints, to use Unicode directly you type a leading zero. The only problem would be saving the file in the correct codepage - Notepad++ should be...

All the documentation you can find online saying to use '^' only applies to Windows's cmd.exe! It is immensely annoying when people keep repeating this as advice for DOS - and no doubt this style of confident-but-wrong responses will only get more frequent, since it's basically what ChatGPT does...

What you are saying is that every program, for every system, should either be written in C, or link with a C library. Or you're even assuming that this is already the case, as if C was somehow fundamental to how computers function and there was no way - or at least no reason - to avoid it, ever...

Yes, the 16-bit addressing modes are different from those in 32-bit mode. Intel originally chose to only allow certain combinations of base+index, so that all of them could be encoded in 3 bits - and this was apparently more important than allowing any register to be used. So base must be BX or...

Compatibility mode is a hardware feature and won't be going away for a long time (you can even still have 16-bit protected mode segments mixed with 32- and 64-bit). Without doing any further research on this, I assume your code is running in ring 0 under UEFI, so even if there is no GDT entry...

I'm not entirely sure I understand what you're trying to do here. Generate machine code that runs the same in both 32- and 64-bit mode? Why not use (or create, if running on UEFI?) a compatibility segment descriptor for the 32-bit code? In long mode, any update to a 32-bit register will zero...

For maximum portability today, you'd write your emulator in JavaScript. Could possibly be made to run on an 8088 too - with a looooooooooooot of patience. But that's kind of the antithesis of what this forum is about.

Of course the V20 is obsolete. So is CP/M. But having an x86 CPU run 8080 code natively is more interesting, I think, than doing the same in software emulation :)

Yes, it's a lot simpler to have separate vectors. Possibly also for BIOS and BDOS calls, depending on how the code for those is implemented. Was just pointing out a theoretical possibility of how to reuse a single one for both entering 8080 mode and then calling back. Also DOS reserves the INT...