dos - Omit vowels from string in x86 assembly -

how can omit vowels string? tried using je instead print out z when loop line 0105.

here code without , loop respectively

without

with

you write 15 (0x0f) bytes file, second version has 20 bytes (0x14), resulting .com file contains code cmp dl, 0x41 , first byte of je opcode. kind of luck when run it, displays z , finishes without taking down whole dos executing random garbage memory.

using proper assembler may bit easier, guess nasm has win binaries, , it's syntax not far masm/tasm, or debug.exe (which not masm/tasm either). (the point is, nasm free , recent). see first if can find reasonable nasm + dos tutorial.

even using debugger run + verify code is absolutely essential, either dig docs debug.exe , try again cut-down version of letters.com see did, or search other dos debugger (my university provided me turbo debugger borland around 199x). if that, wouldn't need ask why z printed, resolving why lost instructions file.