codesourcerer/emulator

A NES Emulator written in C#

emulator's Issues

When drawing pixels, palette is read as though there was an external read

GetColorFromPaletteRam() is reading from the palette using ppuRead(), which will cause issues with A12 tracking for the MMC3. Need to refactor this to not do that.

https://github.com/CodeSourcerer/Emulator/blob/master/NESEmulator/CS2C02.cs#L626
https://github.com/CodeSourcerer/Emulator/blob/master/NESEmulator/CS2C02.cs#L1029

Refactor the way devices raise an IRQ

This whole idea of having something signal to the CPU an IRQ happened is apparently flawed:
https://github.com/CodeSourcerer/Emulator/blob/master/NESEmulator/CS6502.cs#L152-L160

What I need to do is poll all connected devices on the bus to determine if an IRQ is being raised, that way multiple devices can trigger an IRQ correctly.

The simplest way I can think of off the top of my head would be to create an interface for this where any device that can raise an IRQ would implement.