# DOSBox config: simulate an Intel 386SX-16 (1988), the slowest 386 # desktop CPU JoeyLib could realistically be run on. Use this floor # to verify the DOS port still hits its frame budget on the bottom of # the 386 stack rather than coasting on host CPU. # # The 386SX is identical to the 386DX in instruction set; the only # difference is the 16-bit external bus (vs 32-bit on DX), which slows # memory-bound code. DOSBox does not model the bus split directly -- # the cycles count below approximates the combined 386SX-16 throughput. # # Notes: # core = normal accurate per-instruction cycles, not # recompiled-to-host (auto / dynamic would # defeat slow-CPU simulation). # cputype = 386 386 instruction set (no 486 BSWAP / # CMPXCHG, no Pentium MMX). # cycles = fixed 2200 community-standard approximation for # 386SX-16 throughput in DOSBox. # DOSBox-Staging deprecates this in favor # of cpu_cycles, but still accepts it. # Vanilla DOSBox and DOSBox-X only know # the old key, so 'cycles' stays for # cross-fork portability. [cpu] core = normal cputype = 386 cycles = fixed 2200