This patch, when applied to DOSbox 0.60 and linked with these library functions, arwin's p-sprint and SDL (with 8-bit surface patch), gets DOSbox running on the psp. Later versions use an array too large to fit in the PSP memory for indexing memory pages while this version has high level emulation of dpmi.

I've tested SimCity 2000 and Tie Fighter and they run although very slowly, a lot of optimization will be need if this will be usable. Note that stat fails if the root of the memory stick is what is being checked therefore it cannot be mounted. Mounting ms0:/psp works fine though. Also there is currently no mouse or joystick support.