Press the Search button to update the list with all memory locations that have
gone down in value since the last dialog visit. We're going to have to try and
find the heart memory location now because there were only two hearts to start
with.

Look at address line 7E00C3, its current value is 1 and its previous value was
2. Scrolling through the list doesn't reveal any other likely memory locations,
so lets try our luck. Click on the 7E00C3 line, press the Add Cheat button and
type in a new value of say 4 into the dialog that appears and press OK. Press 
OK on the Search for New Cheats dialog to return to the game.

At first sight it looks like 7E00C3 wasn't the correct memory location because
the number of hearts displayed on screen hasn't gone up, but fear not, some
games don't continually update health and life displays until they think they
need to. Crash into another baddie - instead of dying, the number of hearts 
displayed jumps up to 4! We've found the correct location after all!

Now every time you play Addams Family you'll have infinite lives and health.
Have fun finding cheats for other games.

Super FX
========
The Super FX is a 10/21MHz RISC CPU developed by Argonaut Software used as a
game enhancer by several game tiles. Support is still a little buggy but most
games work very well, if a little slowly. Released SNES Super FX games included
Yoshi's Island (best single-player game on SNES, if you like platform games),
Doom, Winter Gold, Dirt Trax FX, StarFox, Stunt Race FX and Vortex. If you're
lucky, you might find a copy of the unreleased Starfox 2 image floating around,
but its sound code is corrupt and you'll need to disable sound CPU emulation to
play it.

Lots of Super FX ROM images available are in an odd, interleaved format that I
haven't worked out an easy way to auto-detect. If Snes9x detects that a 
Super FX game crashes (by executing a BRK instruction), it automatically 
assumes the ROM is in this odd format and demangles the ROM and tries to run
it again. If your ROM image isn't working, you could try selecting the 
Interleave mode 2 option on the ROM load dialog before loading the game to help
out Snes9x.

SA-1
====
The SA-1 is a fast, custom 65c816 8/16-bit processor, the same as inside the
SNES itself, but clocked at 10MHz compared to a maximum of 3.58MHz for the CPU
inside the SNES.

The SA-1 isn't just a CPU, it also contains some extra circuits developed by
Nintendo which includes some very fast RAM, a memory mapper, DMA and, several
real-time timers.

Snes9X includes emulation of most features of the SA-1, enough to play all SA-1
games I've located so far, these include Mario RPG, Kirby Superstar and 
Paradius 3.

C4
==

The C4 is custom Capcom chip used only in the Megaman X2 and Megaman X3 games.
It can scale and rotate images, draw line-vector objects and do some simple
maths to rotate them.

Snes9x's C4 emulation is a direct copy of the ZSNES C4 emulation; Intel-based
ports even make use of ZSNES code. Without zsKnight's hard work, Snes9x would
not have C4 emulation. Many thanks go to him.

Problems With ROMs
==================

If the emulator just displays a black screen for over 10 seconds after you've
loaded a ROM image, then one of the following could be true:

1) You just loaded some random ROM image you've downloaded from the Internet
   and it isn't even a SNES game or you only downloaded part of the image. 
   Snes9x only emulates games designed for the Super NES, not NES, or 
   Master System, or Game Boy, or <insert your favourite old games system here>.
2) If its a Super FX game, chances are its in interleaved2 format, try 
   switching to "Interleaved mode 2" on the ROM load dialog before loading the
   game.
3) Someone has edited the Nintendo ROM information area inside the ROM image
   and Snes9x can't work out what format ROM image is in. Try playing
   around with the ROM format options on the ROM load dialog.
4) The ROM image is corrupt. If you're loading from CD, I know it might
   sound silly, but is the CD dirty? Clean, un-hacked ROM images will display
   [checksum ok] when first loaded, corrupt or hacked ROMs display 
   [bad checksum].
5) The original SNES ROM cartridge had additional hardware inside that is not
   emulated yet and might never be - e.g. Street Fighter Alpha 2 (S-DD1).
The following ROMs are known currently not to work with any version of Snes9x:
- All DSP 1 games except Mario Kart (e.g. Pilotwings, Ballz 3d, Topgear 3000)
- Street Fighter Alpha 2, Star Ocean (missing S-DD1 emulation)
- Exhaust Heat2 (custom co-processor)
- Metal Combat (OBC1)

Sound Problems
==============

No sound coming from any SNES game using Snes9x? Could be any or all of
these:

- If all sound menu options are greyed out, or an error dialog about Snes9x not
  being able to initialise DirectSound is displayed - then DirectSound could
  not initialise itself. Make sure DirectX 6 or above is installed and your 
  sound card is supported by DirectX.

  Installing the latest drivers for your sound card might help. Another 
  Windows application might have opened DirectSound in exclusive mode or 
  opened the Windows WAVE device - WinAmp uses the Windows WAVE device by 
  default - in which case you will need to stop that application and then 
  restart Snes9x. It is possible to switch WinAmp to use DirectSound, in
  which case both Snes9x and WinAmp output can be heard at the same time.

  If your sound card isn't supported by DirectX very well (or not at all) you
  will have to use FMOD's WAVE output option; but WAVE output introduces a 
  0.15s delay between Snes9x generating sample data and you hearing it. 
  Select FMOD's WAVE output by choosing the "FMOD Windows Multimedia" sound
  driver option from the Sound Settings dialog.

- The sound card's volume level might be set too low. Snes9x doesn't alter the 
  card's master volume level so you might need to adjust it using the sound
  card's mixer/volume controls usually available from the task bar or start
  menu.
- Make sure your speakers and turned on, plugged in and the volume controls are
  set to a suitable level.
- You've turned off sound CPU emulation, clicked the Mute button in the
  sound settings dialog, or set the playback rate to "<No sound>".

General sound problems:
- A continuous, crackling sound or buzz can be heard.

  First make sure it is happening in all games - Snes9x still does have one or
  two sound emulation bugs that cause the odd pop, crackle and buzz in a few
  games.

  Once you're happy that it is not just the game you're playing, set the 
  playback rate in the Sound Settings dialog to 22KHz, and uncheck "Stereo" and
  "16bit playback". Next set both sound buffer length and mix values to 10ms,
  then try slowly increasing both values until clear sound can be heard. The 
  ideal is that the mix interval and sound buffer length values should be as
  small as possible. The mix interval value must always be smaller than the
  sound buffer length otherwise sound data will be lost.
  
  If your sound card requires larger values, above, say, 40ms, then it might
  also be necessary to enable the "Generate sample data in sync with sound CPU"
  option to maintain accurate sound emulation.
  
  If all else fails, try selecting the "FMOD Window Multimedia" sound driver 
  option and live with the 0.15s lagged sound that is unavoidable when using 
  the older Windows WAVE sound API.

  Once you have clear sound, set the playback rate, 16bit sound and stereo 
  settings to quality you would like - it might be necessary to tweak the 
  sound buffer length and mix interval values again.

- Sound the lagged/delayed compared to on-screen action. If you're using the
  "FMOD Windows Multimedia" sound driver then delayed sound is unavoidable;
  otherwise your sound buffer length/mix interval settings are too large - if
  you can, reduce their values.
- Sound quality is poor on all games. You might have a noisy sound card 
  (usually cheaper sound cards), turning on 16-bit, interpolated sound, 
  sync-sound and/or increasing the playback rate might help.
- Sound seems to have gaps. Using larger sound buffer or mix interval values
  can cause this; reduce them if you can, or click on the "Generate sample data
  in sync with sound CPU" option.
- Sound is awful in all games. You might have selected a playback rate/stereo/
  8-bit/16-bit combination that your sound card can't cope with. Try setting
  8-bit (uncheck the 16bit playback option), mono (uncheck the Stereo option)
  22KHz from the sound menu and if that cures the problem, try other 
  combinations until you find the best setting that works on your sound card.

If all else fails, try posting a message describing your problem and 
requesting help on the Snes9X message board at the Snes9X web site, 
http://www.snes9x.com

Converting ROM Images
=====================

If you have a ROM image in several pieces, simply rename them so their
filename extensions are numbered: e.g. game.1, game.2, etc. Then, when
loading the ROM image, just specify the name of the first part; the remaining
parts will be loaded automatically.

If they are already in the form sf32xxxa, sf32xxxb, etc., you don't even have
to rename them; just choose the name of the first part from the ROM load 
dialog, as above.

Emulation speed
===============

Emulating an SNES is very processor intensive, with its two or sometimes three
CPUs, an 8 channel digital sound processor with real-time sound sample 
decompression and stereo sound, two custom graphics processors, etc.

If you only have a 486 machine, you will need to stick to using only 8-bit
graphics and minimal or no sound. Disabling the joystick support will also
help.

Full-screen mode is generally faster than windowed mode.

Enabling one of the output image processing modes from the Display Config
dialog can slow down overall emulation speed greatly depending on the type of
game and video RAM speed. Enabling the stretch image option further reduces
emulation speed.

If you want the SNES image to fill your computer screen and want maximum speed,
use the 3dfx bi-linear option if you have a Voodoo 3dfx card, or select output
image mode as none and check the full-screen and stretch image options.

Lowering the sound playback rate, selecting 8-bit mono sound or turning off
interpolated or sync-sound modes, or turning off sound CPU emulation altogether
will also help boost emulation speed.

Credits
-------

- Jerremy Koot for all his hard work on previous versions of Snes96, Snes97 
  and Snes9x.
- Ivar for the original Super FX C emulation, DSP1 emulation work and 
  information on both chips.
- zsKnight and _Demo_ for the Intel Super FX assembler code.
- zsKnight and _Demo_ for all the other ideas I've nicked off them; they've
  nicked lots of my ideas and information too!
- Kreed for his excellent image enhancer routines.
- DiskDude's SNES Kart v1.6 document for the Game Genie(TM) and Pro-Action 
  Replay cheat system information.
- Lord ESNES for some nice chats and generally useful stuff.
- Lee Hyde (lee@jlp1.demon.co.uk) for his quest for sound information and 
  the Windows 95 icon.
- Shawn Hargreaves for the rather good Allegro 3.0 DOS library.
- Robert Grubbs for the SideWinder information - although I didn't use his
  actual driver in the end.
- Steve Snake for his insights into SNES sound sample decompression.
- Vojtech Pavlik for the Linux joystick driver patches.
- Maciej Babinski for the basics of Linux's DGA X server extensions.
- Alexander Larsson for the GGI Linux port code.
- Harald Fielker for some sound interpolation code (not included in this 
  release due to problems).
- Takehiro TOMINAGA for many speed up suggestions and bug fixes.
- Predicador for the Windows icon.
- Lindsey Dubb for the mode 7 bi-linear filter code and the improved 
  colour addition and subtraction code.
- Anti Resonance for his super-human efforts to help get his fast sound CPU
  core and sound DSP core working in Snes9x.

Nintendo is a trademark.
Super NES, SuperScope and Super FX are a trademarks of Nintendo. 
Sun, Solaris and Sparc are all trademarks of Sun Microsystems, Inc.  
Game Genie is a trademark of Lewis Galoob Toys, Inc.
MS-DOS and Windows 95 are trademarks of Microsoft Corp.
Intel, Pentium and MMX are all trademarks of Intel Corp.
Sony is a trademark of Sony Corp.
UNIX is a registered trademark of X/Open.
Glide is a trademark of 3Dfx Interactive, inc.

------------------------------------------------------------------------------
Gary Henderson
gary@snes9x.com