====== Overview ======


----

This section lists the requirements for incorporating extended joystick support in titles development, and compares the features of various versions of the extended joystick. Topics include:

  * [[:documentation:development:opera:pf25:ppgfldr:smmfldr:gspfldr:#xref26299|Requirements]]
  * [[:documentation:development:opera:pf25:ppgfldr:smmfldr:gspfldr:#xref16321|Features of the Extended Joystick]]
  * [[:documentation:development:opera:pf25:ppgfldr:smmfldr:gspfldr:#xref23208|Bit Order]]



===== Requirements =====

Requirements for incorporating extended joystick support in titles development include:

  * Extended joystick
  * Extended joystick driver (included in the Portfolio OS)
  * 3DO Development Station



===== Features of the Extended Joystick =====

The three-axis, extended joystick manufactured by CH Products offers the following features:

  * One four-way switch
  * Three single buttons
  * One fire button
  * One z-axis (throttle) control
  * Movement capability (x and y)
  * Trim controls (x and y)
  * Left shift
  * Right shift
  * Play/pause
  * Stop

The table below provides a description of the features available on various versions of the extended joystick:

<code>
Table 1:   Joystick versions and features.
--------------------------------------------------------
Feature          |Description                              
--------------------------------------------------------
4 single buttons |Includes one fire button in the index 
                 |finger position,and three additional 
                 |buttons (A, B, and C) on the extended 
                 |joystick handle.                         
--------------------------------------------------------
4Ðway switch     |Located in thumb position. The consumer 
                 |extended joystick comes with a single   
                 |4-way switch, or 4 single buttons 
                 |placed in a diamond pattern.  
--------------------------------------------------------
x and y axis     |Consumer versions of the extended    
movement         |joystick are permitted a maximum of   
                 |10-bit precision in each direction.
                 |8-bit precision is the minimum allowed.                 
--------------------------------------------------------
Auxiliary axis   |Consumer versions of the extended    
control          |joystick are permitted a maximum of
                 |10-bit precision in each direction.
                 |8-bit precision is the minimum allowed.     
--------------------------------------------------------
Left-shift,      |These features are implemented with  
right-shift,     |single buttons mounted on the base of 
stop, play/pause |the extended joystick.
--------------------------------------------------------
</code>
Figure 1 shows the placement of controls on the extended joystick.

{{:documentation:development:opera:pf25:ppgfldr:smmfldr:gspfldr:figures:numberjoy.png|Graphic cannot be displayed}}

**Figure 1:** //Extended joystick controls.//



===== Bit Order =====

When 8-bit precision is used, the two least-significant bits are padded with zeros to fill all 10 bits available, as shown in Figure 2.

{{:documentation:development:opera:pf25:ppgfldr:smmfldr:gspfldr:figures:bitlayout.png|Graphic cannot be displayed}}

**Figure 2:** //Bit layout for 8-bit precision.//