GBAC-

After the wild success of the NES emulator I'm going to attempt to make a GBA emulator

Controls:

XInput Controller	Keyboard		GBA
A	Z	->	A
B/X	X	->	B
LShoulder	LShift	->	L
RShoulder	C	->	R
Start	A	->	Start
Back	B	->	Select
DPad Up / Left Joystick	Up	->	DPad Up
DPad Down / Left Joystick	Down	->	DPad Down
DPad Left / Left Joystick	Left	->	DPad Left
DPad Right / Left Joystick	Right	->	DPad Right

Hotkeys:

• I: Current CPU register info (debugging)
• F1: Current PPU Render status (debugging)
• F4: Pause emulation
• F12: Screenshot

Rendering modes:

I added 2 modes of rendering, threaded and not threaded. Threaded rendering will give a performance boost in general. Then for threaded rendering you can enable unsafe rendering, where VRAM/OAM/PAL changes are executed whether the PPU was rendering or not. These can be toggled in the .csproj file, by adding the compiler symbols THREADED_RENDERING and UNSAFE_RENDERING. For UNSAFE_RENDERING to work, THREADED_RENDERING has to be enabled as well.

I have not noticed any differences between UNSAFE_RENDERING and not, except it has crashed in unsafe mode (when it tried to read an out of bounds VRAM entry while rendering, which probably got changed in a different thread). I have prevented the crash as well as I could, but in case it happens, a pixel might be off. It could also happen that PAL/OAM writes happen, but I do not think they will be of much hinderance. There is some performance gain in turning on UNSAFE_RENDERING.

Done:

• ARM instructions
• THUMB instructions
• Render mode 0, 1, 2, 3, 4 (, 5?)
• SWI's
• IRQ handling (ohhh boy was this annoying)
• DMA
• Timers (though not always acurrate)
• Windowing
• Alpha Blending
• Sound
• Debugging options (viewing some registers / charblocks, enabling rendering layers/GFX)
• RTC

To do:

• SIO
• better open bus
• more accurate cycles
• windowing in BM rendering modes
• More GPIO Ports
• Controls mapping

Known bugs:

• Pokemon pinball menu screen popup should be transparent (alphablending issue, used to work)
• Mario & Luigi Superstar Saga video is messed up

_{^{Screenshot sound effect from (https://www.soundjay.com/camera-sound-effect.html)}}