29/5/2000	- changed keys, implemented 2P keys.
		- implemented switch between keypads (CONSOL).

Some 2-pl games working, Pengo 2nd player works fine.

30/5/2000	- implemented cart sig detect for 16k carts

Moon Patrol (unmodified) and Starwars now working.

31/5/2000	- implement detect for Space Shuttle
		- optimised PF gfx a bit.

Space Shuttle working.

1/6/2000	- 2 hour bughunt to get pitfall 2 working
		- traced to bug in mode 4 vert scroll
		
Pitfall 2 & Xevious now working!!! Megamania runs further!

2/6/2000	- fixed mode 5 vert scroll (Countermeasure)


12/7/2000	- fixed "sprite wraparound" bug
                  (Space Invaders, Missile Command, Moon Patrol)

27/7/2000	- added title screen with palette fade-in (WOW!)
		- enabled vsync again
		- added key to switch fps display on/off (F11).
		- ran Good5200 to sort out ROMs.
		- messed about with NTSC/PAL stuff.

13/8/2000	- added support for Tempest and tested Asteroids.
		- put vsync back in.
		
15/9/2000	- HEAVY DUTY changes to HBL updating and finally
		  implemented true scanline renderer.
		- HSCROLL and VSCROLL broken.
		- Some games broken, some fixed.

16/9/2000	- Debugged scanline renderer a bit.
		- Debugged and fixed MODE F (Ballblazer/Fractalus title)
		- Re-implemented HSCROLL
		- Re-mplemented scanline draw delay (40 CPU clocks)
		  (fixed many timing problems (Choplifter))
		- Changed sprite priority and collision detection
		  (broke Zone Ranger :{ )
		- Speed: 60 fps in debug mode for some games!
		  (P166MMX + S3 Trio + S3VBE).

18/9/2000	- Concentrated on fixing "Star Raiders"
		- Fixed bug with DLI on "blank" mode lines
		- Changed display timing so that DL only starts
		  drawing on line 8
		  (Many games MUCH happier now!)

19/9/2000	- Implemented speed throttler (fairly accurate for
		  both NTSC 60Hz and PAL 50Hz)
		- 3 Settings: None, 60/50Hz, 30/25Hz (half speed :)

22/9/2000	- Fixed PF DMA bug (disabled PF scanline update if
		  PF DMA not on) - Ballblazer now runs!
		- Re-implemented VSCROLL (and the same bugs came
		  crawling back... )

23/9/2000	- Fixed VSCROLL
		- Fixed for debug monitor stuff

3/10/2000	- Fixed up collision detection a bit.
		- Fixed up runtime debug out to go to 5200.log
		
8/10/2000	- Added command-line switch for PAL mode.


TODO:
1. fix collision detection
2. fix gfx bug (extra line of text drawn)
 
