INTRODUCTION
------------

Stella is the best emulator of Atari 2600 game
console, running on many different systems, such as
Linux, Solaris, Windows, MacOS/X WinCE, OS/2, GP2X.

It has been initially written by Bradford Mott
(see http://stella.sourceforge.net/)

PSP2600 is a port on PSP of the version v2.2 of
Stella. It's based on the work of David Voswinkel,
who was the first to port Stella to PSP.

CONTROL
------------

PSP        Atari 2600
  
Cross      Fire
Triangle   L Diff A 
Circle     L Diff B
Square     R Diff A

LTrigger mapping :

  PSP        Atari 2600
    
  Square     Hotkey FPS
  Triangle   Hotkey Load state
  Cross      Hotkey Save state
  Circle     Hotkey swap joystick
  Up         Hotkey flicker
  Down       Hotkey flicker
  Left       Hotkey render
  Right      Hotkey render

RTrigger mapping :

  PSP        Atari 2600 
    
  Square     Escape
  Triangle   Reset
  Cross      Hotkey auto-fire
  Circle     Select
  Up         Up
  Down       Down
  Left       Hotkey Dec Fire
  Right      Hotkey Inc Fire


Analog     Joystick

LTrigger   Toogle with L keyboard mapping
RTrigger   Toggle with R keyboard mapping

Analog     Joystick

Press Start  + L + R to exit and return to eloader.
Press Select         to enter in emulator main menu.
Press Start          open/close the On-Screen keyboard

In the main menu

RTrigger   Reset the emulator

Triangle   Go Up directory
Cross      Valid
Circle     Valid
Square     Go Back to the emulator window

The On-Screen Keyboard of "Danzel" and "Jeff Chen"

Use Analog stick to choose one of the 9 squares, and
use Triangle, Square, Cross and Circle to choose one of
the 4 letters of the highlighted square.

You can also use IR keyboard. Edit the pspirkeyb.ini
file to specify your IR keyboard model, and modify
eventually layout keyboard files in the keymap
directory.

The following mapping is done :

IR-keyboard   PSP

Cursor        Digital Pad

Tab           Start
Ctrl-W        Start

Escape        Select
Ctrl-Q        Select

Ctrl-E        Triangle
Ctrl-X        Cross
Ctrl-S        Square
Ctrl-F        Circle
Ctrl-Z        L-trigger
Ctrl-C        R-trigger

In the emulator window you can use the IR keyboard to
enter letters, special characters and digits.


LOADING ROM FILES (.A26 or .BIN)
------------

If you want to load rom images in the virtual drive
of your emulator, you have to put your rom file (with
.zip, .bin or .a26 file extension) on your PSP memory
stick in the 'roms' directory. 

Then, while inside Atari 2600 emulator, just press
SELECT to enter in the emulator main menu, choose
"Load ROM" and then using the file selector choose one
game file to load in your emulator. Back to the
emulator window, your game should run automatically.

LOADING KEY MAPPING FILES
------------

For given games, the default keyboard mapping between
PSP Keys and Atari 2600 keys, is not suitable, and
the game can't be played on PSP2600.

To overcome the issue, you can write your own mapping
file. Using notepad for example you can edit a file
with the .kbd extension and put it in the kbd 
directory.

For the exact syntax of those mapping files, have a
look on sample files already presents in the kbd
directory (default.kbd etc ...).

After writting such keyboard mapping file, you can
load them using the main menu inside the emulator.

If the keyboard filename is the same as the rom file
(.a26) then when you load this rom file, the
corresponding keyboard file is 
automatically loaded !

You can now use the Keyboard menu and edit, load and
save your keyboard mapping files inside the emulator.
The Save option save the .kbd file in the kbd
directory using the "Game Name" as filename. The game
name is displayed on the right corner in the emulator
menu.

CHEAT CODE (.CHT)
----------

  You can use cheat codes with this emulator.  You
can add your own cheat codes in the cheat.txt file
and then import them in the cheat menu.  

  All cheat codes you have specified for a game can
be save in a CHT file in 'cht' folder.  Those cheat
codes would then be automatically loaded when you
start the game.

The CHT file format is the following :
#
# Enable, Address, Value, Comment
#
1,36f,3,Cheat comment

  Using the Cheat menu you can search for modified
bytes in RAM between current time and the last time
you saved the RAM. It might be very usefull to find
"poke" address by yourself, monitoring for example
life numbers.

To find a new "poke address" you can proceed as
follow :

Let's say you're playing Moon patrol and you want to
find the memory address where "number lives" is
stored.

. Start a new game in Moon patrol
. Enter in the cheat menu. 
. Choose Save Ram to save initial state of the memory. 
. Specify the number of lives you want to find in
  "Scan Old Value" field.
  (for Glouton the initial lives number is 3)
. Go back to the game and loose a life.
. Enter in the cheat menu. 
. Specify the number of lives you want to find in
  "Scan New Value" field.
  (for Moon patrol the lives number is now 2)
. In Add Cheat you have now one matching Address
. Specify the Poke value you want (for example 3) 
  and add a new cheat with this address / value.

The cheat is now activated in the cheat list and you
can save it using the "Save cheat" menu.

Let's enjoy Moon patrol with infinite life !!

COMMENTS
------------

You can write your own comments for games using the
"Comment" menu.  The first line of your comments
would then be displayed in the file requester menu
while selecting the given file name (roms, keyboard,
settings).

SETTINGS
------------

You can modify several settings value in the settings
menu of this emulator.  The following parameters are
available :

Sound enable : 
  enable or disable the sound

Active Joystick : 
  Joystick player, it could be 1 or 2

Paddle enable :
  enable or disable paddle

Paddle speed :
  specify paddle speed factor (from 1 to 3)

Speed limiter :
  limit the speed to a given fps value

Skip frame : 
  to skip frame and increase emulator speed

Display fps : 
  display real time fps value 

Render mode : 
  many render modes are available with different
  geometry that should covered all games
  requirements

Delta Y : 
  move the center of the screen vertically

Vsync : 
  wait for vertical signal between each frame displayed

Flicker mode : 
  set flicker mode (none, simple, phosphor or average)
  
Swap Analog/Cursor : 
  swap key mapping between PSP analog pad and PSP
  digital pad

Auto fire period : 
  auto fire period

Auto fire mode : 
  auto fire mode active or not

Display LR led : 
  draw a small blue rectangle in top of the screen
  when trigger keys are pressed

Clock frequency : 
  PSP clock frequency, by default the value is set
  to 222Mhz, and should be enough for most of all
  games.


FLICKERING 
------------

On several games such as Asteroids or Missile
Command, the screen flicks, or the color are dark.
You can then change the Flicker mode parameters in
the Settings menu. For example, Asteroids is very
nice using the "Simple" anti-flicker mode.

AUTO-FIRE
------------

It may happens that autofire can not be stopped. 
You have then to go to the settings menu and 
set auto fire option to off ...


  Enjoy,

            Zx

