NASM sources, DOSBox/FreeDOS Debug/Unicorn harness, captured output and 31 assertions backing the ankurm.com article "INT 3 vs INT 21h in 8086 Assembly". Co-Authored-By: Claude Sonnet 5.5 <[email protected]> Claude-Session: https://claude.ai/code/session_01KqJyCidz3ZgRyHABv2GVJh
14 lines
402 B
NASM
14 lines
402 B
NASM
; bp_target.asm -- a flat 16-bit routine used by the Unicorn breakpoint experiment.
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; Three one-byte INC CX instructions, so a two-byte CD 03 patch on the first one
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; overwrites the first byte of the second one too.
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bits 16
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org 0x7C00
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start:
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xor cx, cx
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site:
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inc cx ; 41 <- breakpoint goes here
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inc cx ; 41
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inc cx ; 41
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done:
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nop
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