tugboat.c: correct AY chip type and clock, some cleanups [Alex Jackson]
k005289.c: correct comments, name functions after pin names on schematic (nw)
(MESS) pc/xt/at: added basic implementation of the Programmers Development System ISA card.  The PDS editor software requires the hardware present to start up.  Some core work will need to be done to get any communications working, however. [Barry Rodewald]
AICA: EFREG is mapped every other word, not every word.  Fixes memory trashing in all Naomi/DC/AW games. [O. Galibert, R. Belmont]
Fixed a nasty issue around convergence by defaulting to Gaussian elemination for 5x5 and 6x6 matrices. This prevented pong from starting. 
In addition, removed a number of hacks around start-up conditions. All nets are now defaulted to "0" at startup. Much cleaner.
Added a 74LS629 device which yet needs to be enabled.
preliminary ADM decoding
Implemented a fallback to Gaussian elimination if Gauss-Seidel exceeds a certain number of iterations.
(MESS) amstrad: added the option of having nothing attached to the joystick ports.  Mostly to avoid the cursor keys and the default joystick inputs clashing. (no whatsnew)
(MESS) New skeleton driver:
- Roland Sound Canvas SC-55 [Stefan Lindberg]


nw: Time to play "what's the CPU?".  seems to be 8-bit little-endian, might be 
i8x9x, might not be.  Current ROM mapping is definitely wrong.