Posted January 14, 2017
DOSBox also emulates CPU:286/386 realmode/protected mode, Directory FileSystem/XMS/EMS, Tandy/Hercules/CGA/EGA/VGA/VESA graphics, a SoundBlaster/Gravis Ultra Sound card for excellent sound compatibility with older games...
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The protected mode was introduced since 286, not means DOSBox can only emulate a 286/386 machine.
It will become slower in an ARM CPU, but performance is not a big problem.