Driving the Coupé

I decided to take a look at the SAM Coupé driver, because I saw some weird unused code in the palette init that I cleaned up. After changing the video emulation to use the new scanline-based update features in MAME, adding proper vblank areas and using all that properly emulate the LPEN and HPEN registers we get from this:

To this:

However, currently most of the work is still cleanups, like the I/O ports. Major areas that still need cleaning up are the memory banking and video drawing routines. When the driver is in good shape, we can take a look at adding the missing border areas or features like the Real Time Clock and hard drives (or even tapes).