Game Engine

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Game Engine

• EECS150 Fall2006
• Lab Lecture 9
• Kenny Duong

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Project Status
Check Point 1 N64 Controller Interface
Check Point 2 NTSC Video
VideoRAM
VideoRAM
Check Point 3 Chipcon RF Transceiver
Check Point 4 Game Engine
Block Diagram of the Design
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Checkpoint 4

• Basic Requirements
• 2-player wireless Battleship
• Find an opponent and start playing
• Place and store ship positions
• Display the game and scores
• Extra Credits
• Feel free to add extra features. Talk to TAs
  about extra credits BEFORE you do it.
• A list of possible extra features and point
  rewards for those features will be published later

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First thing first

• 100 Freedom
• 0 Freedom

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Game Setup

• Possible video output

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Game Board (1)

• Internal game board representation
• It is in the engine. You can decide.
• One possible way
• Use RAM to store the board data
• See the reference RAM implementation in cp4 zip
  file

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Game Board (2)

• For each point on the board, you can use 8 bits
  to represent its status
• Things you need to represent
• Hit or Miss
• Ship Index
• Ship Part Type (Vert. Tail, Hori. Tail, etc.)

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Wireless Battleship?? Three main phases

• In default channel
• Initialize the board
• If you are a client, actively find an opponent
• If you are a server, wait for game request

Initialization Phase

• In game play
• Game play is not real-time
• Maintain communication between systems
• (with KA packets)
• Send your shot and GameIndex
• Receive those from your opponent
• Update the game
• Game over. Go back to Initialization phase

Game Setup Phase
Game Playing Phase
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Initialization Phase
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Initialization Phase

• Packet formats standardize the 32-bit payload.
  You need to decide the proper source address and
  destination address.

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Wireless Communication

• !!! UNRELIABLE !!!
• You must add redundancy to make it reliable
• Send every packet multiple times. We start with
  packetRepeatTimes 3. You can experiment later
  on to find out the optimal value.

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Administrative Info (1)

• Checkpoint 3 due next week
• 50 off one week later
• Plan out a design for checkpoint 4
• No design review, but should be useful for
  project writeup
• Considering extra credit? Plan for it
• Design consideration
• Time allocation

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Administrative Info (2)

• Project grade breakdown
• Checkpoint 1 10
• Checkpoint 2 15
• Checkpoint 3 30
• Checkpoint 4 / Final Checkoff 30
• Report 15

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Administrative Info (3)

• Extra credit
• Up to 20 of total project grade
• Due at the same time as your CP4 check-off
• (either early or standard check-off)
• Not eligible unless you complete all previous
  required project work.
• (Single student groups can submit the blackboxes
  we gave you.)

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Administrative Info (4)

• Miscellaneous
• Turn off your FPGAs when you leave
• Its not nice to screw other people up
• )

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Game Setting Phase (1)

• Parameters
• Packet repetition times
• packetRepeatTimes 3
• Resend KA
• speed once every 1/4 seconds
• You could try different values for packet
  repetition later
• To differentiate between games on the same
  channel, introduce a KAIndex. It starts from 0
  increments after every KA is sent.

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Game Setting Phase (2)

• Packet Format
• You must transmit a KA index with your packets

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Game Setting Phase (3)

• Depending on whether you are a client or a
  server, there are two different paths
• Client
• Send KA Packets
• Receive KA-Ack Packets
• Update board with placed ships
• Keep track of KA Index
• Server
• Receive KA Packets
• Send KA-Ack Packets
• Update board with placed ships
• Keep track of KA Index

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Game Playing Phase (1)

• Packet Format

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Game Playing Phase (2)

• KA-Alive Scheme is the same is in initialization
• Communication to VideoRam is more complicated
• Send Row,Col with Shot Packet
• ShipIndex with Sunk Packet
• See Design Document for more detailed description
  of state transitions

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VideoRAM

• You are free to choose any implementation
• For your reference, in our implementation, we
  have dedicated groups of signals for Read/Write
  Ship positions, and for Write characters on the
  screen
• Refer to the Checkpoint assignment for detailed
  port information

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Project Tips (1)

• Design
• Get used to debugging
• An unverified module is useless
• Refer to lab4 and lab5
• Start from SIMULATION
• Testing
• Multiple boards, different addresses, different
  orderings, etc.

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Project Tips (2)

• Requirements
• Finish these first
• Make sure it works well
• Shouldnt depend on a certain N64 controller
• Should work on multiple boards
• Extra Credit
• Finish early, its worth 5
• Keep your required version separate
• Dont touch it while you work on extra credit!

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Project Writeup

• Includes
• Block diagrams
• Bubble-and-arc diagrams
• Comments
• NO SCHEMATICS (Theyre too detailed)
• Use your design reviews!
• Documentation helps you debug
• Also makes it easier for us to help you
• More details will be posted later

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• Enjoy Life