As PicoDrive is multiplatform emulator, this is GP2X specific part of readme
about configuration.


Configuration
-------------

1. "Renderer"
8bit fast:
This enables alternative heavily optimized tile-based renderer, which renders
pixels not line-by-line (this is what accurate renderers do), but in 8x8 tiles,
which is much faster. But because of the way it works it can't render any
mid-frame image changes (raster effects), so it is useful only with some games.

Other two are accurate line-based renderers. The 8bit is faster but does not
run well with some games like Street Racer.

2. "Accurate timing"
This adds some more emulation precision, but slows the emulation down. Whithout
this option some games do not boot (Red Zone for example), others have sound
problems.

3. "Accurate sprites"
This option improves emulation of sprite priorities, it also enables emulation
of sprite collision bit. If you see one sprite being drawn incorrectly above
the other (often seen in Sonic 3D Blast), you can enable this to fix the problem.
This only works with the default renderer (see first option).

4. "Show FPS"
Self-explanatory. Format is XX/YY, where XX is the number of rendered frames and
YY is the number of emulated frames per second.

5. "Frameskip"
How many frames to skip rendering before displaying another.
"Auto" is recommended.

6. "Enable sound"
Does what it says. You must enable at least YM2612 or SN76496 (in advanced options,
see below) for this to make sense.

7. "Sound Quality"
Sound rate and stereo mode. If you want 44100Hz sound, it is recommended to enable
the second core (next option).

8. "Use ARM940 core for sound"
This option causes PicoDrive to use ARM940T core (GP2X's second CPU) for sound 
(i.e. to generate YM2612 samples) to improve performance noticeably.

9. "6 button pad"
If you enable this, games will think that 6 button gamepad is connected. If you
go and reconfigure your keys, you will be able to bind X,Y,Z and mode actions.

10. "Genesis Region"
This option lets you force the game to think it is running on machine from the
specified region.

11. "Use SRAM savestates"
This will automatically read/write SRAM savestates for games which are using them.
SRAM is saved whenever you pause your game or exit the emulator.

12. "GP2X CPU clocks"
Here you can change clocks of both GP2X's CPUs. Larger values increase performance.
There is no separate option for the second CPU because both CPUs use the same clock
source. Setting this option to 200 will cause PicoDrive NOT to change GP2X's clocks
at all.

13. "[advanced options]"
Enters advanced options menu (see below).

14. "Save cfg as default"
If you save your config here it will be loaded on next ROM load, but only if there
is no game specific config saved (which will be loaded in that case).

15. "Save cfg for current game only"
Whenever you load current ROM again these settings will be loaded (squidgehack and
RAM settings will not take effect until emulator is restarted).

Advanced configuration
----------------------

Enter [advanced options] in config menu to see these options.

1. "Scale 32 column mode"
This enables hardware scaling for lower-res genesis mode (where width is
32 8-pixel tiles, instead of 40 in other mode).

2. "Gamma correction"
Alters image gamma through GP2X hardware. Larger values make image to look brighter,
lower - darker (default is 1.0).

3. "Emulate Z80"
Enables emulation of Z80 chip, which was mostly used to drive the other sound chips.
Some games do complex sync with it, so you must enable it even if you don't use
sound to be able to play them.

4. "Emulate YM2612 (FM)"
This enables emulation of six-channel FM sound synthesizer chip, which was used to
produce sound effects and music.

5. "Emulate SN76496 (PSG)"
This enables emulation of additional sound chip for additional effects.

Note: if you change sound settings AFTER loading a ROM, you may need to reset
game to get sound. This is because most games initialize sound chips on
startup, and this data is lost when sound chips are being enabled/disabled.

6. "gzip savestates"
This will always apply gzip compression on your savestates, allowing you to
save some space and load/save time.

7. "USB joy controls player X"
If you are able to use USB joysticks with your GP2X, this options selects which
player the joystick controls.

8. "Don't save config on exit"
This will disable config autowrite on exit (which might cause SD card corruption
according to DaveC).

9. "craigix's RAM timings"
This overclocks the GP2X RAM chips, but may cause instability. Recommended if you
use the second core for sound. Needs emulator restart to take effect.
See this thread:
http://www.gp32x.com/board/index.php?showtopic=32319

10. "squidgehack"
Well known way to improve the GP2X performance. You must restart the emulator
for the change of this option to take effect.


Key configuration
-----------------

When you select "Configure controls" from the menu, you enter a key configuration
mode, where you use SELECT to change an action, and then press a key you like to
bind to that action. You can press the same key again to unbind. Select "DONE"
action and press any key to finish.


