Finally found a Dreamcast emulator with StateSave

I was using nullDC as my default Dreamcast emulator for a while, and though it performance reasonably fine, it lacks a critical feature that made me use emulator in the first place: the ability to save state, so that I can finish a game without spending huge amount of hours.

Eventually, I found an alternative called Demul.  But then after following some instruction videos, I was even confuse than before.  Eventually I was following this tutorial video,  and realized that I should use the official download to start first, which is from here.  And then i get the BIOS from here, and put them into the roms folder. And then I set up the XBox360 controller, and then selected BIOS "1.01d" (I was NOT ablet to use 1.022), and then everything works fine.

But then state saving is odd:

• To use the feature, you need to map the key of Save and Load state to a certain button.  I mapped them to keys ASZX.
• There's a bug that cause the application to crash if you map those Save/Load state button to XBox 360 control.  So make sure you do not do that.
• If you switch to another game, you should RESTART the application and then load that game.  Otherwise, Save/Load state will be confused and result in mess up State saving files.