Manual Additions: Peripherals
There are two types of peripheral to consider in the Net
Yaroze environment: Controllers and Memory cards.
[Names of Peripherals] [Controller
Recommendations] [Analog Joystick] [neGcon] [Memory Cards]
The following conditions should be met by the
game for it to pass the tests placed upon it by the European
Quality Assurance Group, and are recommended for Net Yaroze
Members.
Most of the sample code supplied only supports
a single Controller and does not detect the type of Controller
connected - in a commercial title this would fail QA tests.
Physically, the Analog Joystick consist of two
standard joysticks, linked by a control panel with standard
switches. The joystick can act in either digital or analogue
mode.
Make sure you include a Calibration menu (0 position calibration,
idle movement, sensitivity etc.) in your application.
The 8 byte Controller packet (giving the
status of the Controller) which can be returned at every vsynch
call back consists of the following for the Analog Joystick.
The input data is transmitted
as 6-byte serial data and the contents are as follows.
Make sure you include a Calibration menu (0 position calibration,
idle movement, sensitivity etc.) in your title.
The 8 byte Controller packet (giving the status of the
Controller) which can be returned at every vsynch call back
consists of the following for the neGcon.
Note The value varies by twisting NegCon not by
pressing a button.
See the controller packet for
an Analog Joystick, in the table, below.
1 - Switch Data
0 is returned when the button
is pressed otherwise 1 is returned. Unused bits return 1. The
return values comply with the standard Controller specifications,
however, they can be changed by BIOS if necessary.
2 - Switch Data
As above.
3 - Twist Data
The title needs to be designed
so that neGcon's twist data value is around 128 when it is
released. However, a variation of +/-8 should be allowed for to
take account of variations that may occur between different
neGcons and the different effect gravity may have on Controller
buttons if the Controller is held in a different position. (The
specified +/-8 allowance may be changed later if it proves
unsuitable but this does not affect your current title.)
Remember that you are
recommended to include a calibration option in any title which
uses a neGcon Controller as individual neGcons may differ
slightly.
4 - I button Data
The more this button is
pressed, the bigger value is returned. The title should be
designed so that a value of 16 or less is returned when it is
released.. The software should consider 16 or less as the button
not pressed. This error margin allows for variations between
different neGcons, as described in 3 - Twist Data, above -
the specified value of 16 or less may be changed later if it
proves unsuitable but this does not affect your current title.)
The maximum value returned when pressed should be not less than
192(C0H).
5 - II button Data
Same as I button, above.
6 - L button Data
Memory cards are the
removable storage medium used by the PlayStation to save and
recover game sessions (game save file). A Memory card contains
120K of static non volatile RAM. This is divided conceptually
into 15 slots, each of 8k.
Memory cards have the
advantage of small size and ruggedness (there are no moving parts
and no batteries) but they are relatively slow to access.
General Features of
Memory Cards
Capacity: 120 Kilobytes
Access Speed: 10 Kilobytes per
second
Life span: 100,000 reads
guaranteed
As well a being
accessed by the application that created the game save
file, each file will also need to be compatible with the
OSD memory card management program built into the ROM of
each PlayStation.
Different versions of
the OSD are available for each PlayStation territory
(i.e. European, Japanese, American).
The OSD program
displays each save game file as a number of icons plus a
textual title. Each icon displayed relates to a slot
used. This information is provided by a header that must
be included at the start of the save game file.
Filenames used for
memory card save games are based upon the product code
for professional games - you of course are free to choose
one that suits your purposes.
The file name is in
the following format:
BESLES12435plusthis
Some Rules on
Title Names
Choose either Shift-JIS or ASCII code.
Do not mix them.
Use a maximum 32 ASCII letters (32
Byte). If less than 32 characters, please put null letter
(0x00) at the end or fulfil the vacant part with blank
letter.
The Save Game File
Header format is as follows.
In the
header file there is provision for three icon images, as
below, which allows animation.
The Memory card save
game file header Text Name must be stored in Kanji
(Japanese Shift-JIS) type character coding and not the
normal ASCII. (If ASCII were used the game header file,
the title would not be displayed correctly if it is
longer than 16 characters - 32 is the total possible. )
As can be seen from
the table above it is possible to have animated icons in
the save game. There are three frames available and they
are cycled automatically by the OSD.
(If two slots are
used per save, a two frame animation is allowed; with
three slots, a three frame animation).
The Icon is a 16 * 16
image with 4 bit colour depth.
Note: do not
use animated icons for European titles (i.e. only use
type 0x11) if your save occupies a single slot. 3.2.3
Memory cards are slow
to recognise and access. Memory card accesses, therefore,
should be kept to a minimum and when they are made be as
efficient as possible.
As a Memory card is
divided into 8k slots, the minimum possible number should
be used. Writes to the card system are always done as
multiples of 8K, so if the intended game save is 8K + 1
bytes, it will use two slots, taking twice as long to
save as one slot and take twice as much space as a save
that is only 1 byte smaller.
In this example,
there is only 1 byte over so some compression/economising
of the data could probably be achieved. For over spill
which cannot be squeezed into 8k, the alternative is to
save more data in the in the file and use up the wasted
space. It costs nothing in terms of resources or
performance.
Many games in these
genres benefit from allowing the user to save several
sessions concurrently. This allows the user to backup
before undertaking hazardous stages, or to approach a
complex problem from several angles simultaneously.
This can be achieved
in two ways, firstly by having several saves within the
same file. For example if the data required by the save
game is only 2K, you can save 4 games within the same
slot.
Alternatively, the
format of the save game filename allows for multiple
saves from the same game, because there are nine
characters in the memory card file name left available
for user allocation. This could be used to store a user
entered string that is a description of the game save at
that point in the game.
Better still, add an
internal character field that allows for a textual
description of the current stage of the game and display
this when displaying a list of all the save games on the
memory card. BESLES-12345level2 In some games the memory
card facilities play a very important role. A classic
example of this is XCOM: Enemy Unknown, which
would be very hard, if not impossible to finish without
frequent memory card access. These unfortunately are slow
and so disrupt the flow of play. One solution would be to
save games into RAM as a quick save, with the option to
commit the game to the card at any time. This is only
feasible if the game never crashes out and there is room
in memory for the save game(s).
It is not possible to
lengthen a file saved on a Memory card once it is
created, therefore when the file is created it should as
large as it will ever need to be.
- Is the Memory card operation
display working? (Display of icon, or file name,
etc.)
- Can Memory card be formatted?
(On-screen instructions and statements are
correct?)
- The "formatting menu"
options should include a dialogue such as
"The Memory card ID is not formatted yet. Do
you want to format that? Yes? or No?". Then,
when "Yes" is chosen, saving should
start and when "No" is chosen, the menu
should exit from save mode.
- Check what happens when there
aren’t enough empty blocks in the Memory
card for a game save.
- Check what happens when the
Memory.