Can this emulator play PS1 games in the future?

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This: https://github.com/DHrpcs3/rpcs3/commit/...1dc0a58e1a

DH set up a separate thread to run ELF files based on the ARM architecture (ARM v7 from the Cortex-A9 MPCore). In the commits afterwards there were some basic interpreter and disassembler implementations and finally the integration with the ELF loader.
While this is not really useful now, I believe the purpose would be to run Vita games in a parallel thread so later we could emulate the connectivity between PS3 and Vita games.

from what I can read: he defines four types of CPU: MIPS, PPU, SPU and ARMv7. They sound more like an attempt to more genericity in the way to handle cpus. This emulator is going to do some low level emulation ?

Possibly, yes. We're still not sure about how the CPU emulation will occur inside the emulator, but it would be really interesting and a great proof of concept to implement.

Possibly, yes. We're still not sure about how the CPU emulation will occur inside the emulator, but it would be really interesting and a great proof of concept to implement.

by just looking some rpcs3 source, I noticed some references to "ARM9" and not to ARMv7. It is misleading for someone who knows about ARM family. ARM9 (ARMv4/5) is an older CPU which were used before the cortex family are released. ARMv7 is perfect as a designation rather than ARM9 for ARM[ Cortex A]9. Hopefully the presence of directory ARMv7 dispels the doubt I had when reading those "ARM9" in comments.

hlide, DH just mistyped it, when added initial commit.

I believe DH renamed later all ARM9 (Cortex A9) references to the proper ARMv7 (ARM family). Looking at the current github code I can't find ARM9 anywhere anymore.