This gets to the other sense of your query: "I want to make a disassembler". The source for ndisasm is available, and it handles many of the descendants of 8086, not just 8086, itself (which seriously clutters it, if all you want is an 8086 or even 80386 disassembler), but it is not self-contained and has a heavy dependency on the rest of the distribution.
8086 disassembler download utility
Download File: https://terpturpropki.blogspot.com/?file=2vJSQk
And then you've just disassembled a disassembler that also happens to do CPU emulation, like Fake86 does - but only for the 8086. You'll have to make the absolute addresses relative (using the original relocation table as a guide), to make is re-assemblable. Once you do that, you can work on the source. The opcode table is in clear view (if you display it as text) - both when seen in the packed and unpacked versions of debug.exe.
I might port the DAS disassembler to the x86, since items (a)-(f) are already incorporated into DAS's design. I've only ever ported it to the 8051, 6800, 6809 and 8080/8085 (and Z80) up to now; but the transition from 8085 to 8086 is relatively small. To that end, I might hack something out of Fake86. That's mostly abandonware, now, since the author replaced it by XTulator, as Fake86 was written when the programmer was relatively new to C. You might also be able to hack something directly out of DosDebug's opcode tables (their "instr.*" files).
The DisassemblerHackman Disassembler 9.0 is an ultra fast multi processor disassembler, capable of disassembling code at a rate of 250 Kb/sec (PIII/900 MHz). The opcodes cover all x86 Intel and AMD architecture, starting at 8086 and ending at 3DNow! and Pentium 4 specific instructions. With Hackman Disassembler you have a multi-disassembling suite integrated into one program with a handy interface. Opcode sets are available for Intel 8086/80286/80386/80486 (*), Intel Pentium/Pro/MMX/II/III/P4 (*), AMD 3DNow! (*), 1802 (*), 6502/6510/8500/8502, 65816, 65C02/65SC02, 65CE02, Motorola 6800/6802/6808 (*), Motorola 6801/6803 (*), Motorola 6805/146805 (*), Hitachi 6809/6309, 8085, Zilog Z80, Gameboy CPU, Java Bytecode. Asterisk (*) denotes detailed online help availability.
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