Detecting a PS2 Emulator: When 1*X does not equal X

Re:Detecting a PS2 Emulator: When 1*X does not equal X by xcv123 on Sunday June 09, 2024 @10:07PM (#40629456)

You start by reading hardware documentation and you don't need to understand the machine at an electronic level. It's not a simulation of digital circuits. It doesn't need to be that complicated. An 8-bit CPU is a simple state machine with only a few bytes of state (registers). You can read the program one byte at a time and simulate whatever operation the CPU would do after reading that byte. They are very simple operations like adding and subtracting numbers, loading and storing bytes.

http://www.6502.org/users/obelisk/6502/registers.html

http://www.6502.org/users/obelisk/6502/instructions.html

Your 6502 CPU emulator would read the next few bytes of the program, interpret the bytes as an instruction, execute the instruction, which involves updating a couple of registers/counters in the CPU, doing some arithmetic or bitwise operations, and possibly loading or storing a byte of data from one location to another. This process is then repeated in an endless loop.

It is a simulation of the fetch-decode-execute cycle.

https://en.wikipedia.org/wiki/Instruction_cycle

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Re:Detecting a PS2 Emulator: When 1*X does not equal X by purple-leafy on Sunday June 09, 2024 @11:46PM (#40629949)

Thanks for that! You put it into a very understandable form

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Re:Detecting a PS2 Emulator: When 1*X does not equal X by xcv123 on Sunday June 09, 2024 @11:56PM (#40629993)

You're welcome.

I learned about the basics here http://www.emulator101.com

Then I read the docs at NESdev Wiki and eventually wrote my own NES emulator.

https://www.nesdev.org/wiki/Nesdev_Wiki

If you have good documentation then you're just following the specs and turning that into code. Next level difficulty is reverse engineering the hardware, figuring out how it works when there isn't any documentation. These guys did that for NES back in the 90s and early 2000s, writing little test ROMs to see what the hardware does, in addition to whatever official or unofficial developer docs they could find.

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