Basic i50Phone

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Basic i50Phone

• EECS150 Fall 2007 - Lab Lecture 10
• Allen Lee

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Example
MyTeam
UsrName1
UsrName2
UsrName3
M
S
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Example
MyTeam
UsrName1
UsrName2
UsrName3
UsrName4
Dialing User UsrName2 Cancel(B)
M
S
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Example
MyTeam
UsrName1
UsrName2
UsrName3
UsrName4
Dialing User UsrName2 Cancel(B)
User Unavailable
M
S
10
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Example
MyTeam
UsrName1
UsrName2
UsrName3
UsrName4
Dialing User UsrName2 Cancel(B)
User Unavailable
Dialing User UsrName3 Cancel(B)
M
S
10
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Example
MyTeam
UsrName1
UsrName3
UsrName2
UsrName3
UsrName4
Dialing User UsrName2 Cancel(B)
User Unavailable
Dialing User UsrName3 Cancel(B)
Connection Established
M
S
10
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Example
MyTeam
UsrName3
UsrName2
UsrName3
UsrName4
Dialing User UsrName2 Cancel(B)
User Unavailable
Dialing User UsrName3 Cancel(B)
Connection Established
Connection Terminated
M
S
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Example
MyTeam
UsrName2
UsrName3
UsrName4
Dialing User UsrName2 Cancel(B)
User Unavailable
Dialing User UsrName3 Cancel(B)
Connection Established
Connection Terminated
M
S
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Example
MyTeam
UsrName2
UsrName3
UsrName4
User Unavailable
Dialing User UsrName3 Cancel(B)
Connection Established
Connection Terminated
Call From UsrName4 Acc(A)/Rej(B)
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S
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Example
MyTeam
UsrName4
UsrName2
UsrName3
UsrName4
Dialing User UsrName3 Cancel(B)
Connection Established
Connection Terminated
Call From UsrName4 Acc(A)/Rej(B)
Connection Established
M
S
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Overview

• Introduction to Checkpoint 4
• Adding to Checkpoint 1
• Adding to Checkpoint 2
• Communications protocol
• Advice
• Extra Credit

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Checkpoint 4 Everything in this circle
Checkpoint 4 (Communications and Registry)
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Checkpoint 4 Additions
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Adding to Checkpoint 1

• Audio Buffer
• Previously stored all audio data into one huge
  FIFO and local playback.
• Must now support sending and receiving audio data
  from transceiver.
• AC97 Controller
• Remains the same
• Volume and Mute signals now come from user input
  module in CP2.

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Old Audio Buffer

• Data output from FIFO goes back to Audio
  controller

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New Audio Buffer

• Must now support sending and receiving from
  wireless transceiver

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Adding to Checkpoint 2

• User Input Parser
• Keep track of a cursor position (0 through 7) for
  each of the top two regions.
• Only allow the cursor of a particular region to
  change when the focus is on that region.
• When the cursor is on a valid user in the Channel
  region, and A is pressed
• Change the focus to the console.
• Send a call request, and wait for a response.
• Press B to cancel the request and change focus
  to Channel region.
• Ignore incoming calls while requesting a call.
• When a connection established or refused, change
  focus to Channel region.

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Adding to Checkpoint 2

• User Input Parser (contd)
• When the cursor is on a valid user in the
  Connection region, and B is pressed
• Send a disconnect signal
• Focus remains in Connection region
• When there is an incoming call and you are not
  requesting a call
• Change focus to console
• Press A to accept, or B to reject
• In either case, return focus to Channel

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Adding to Checkpoint 2

• Video Display
• Support a registry that stores up to 8 users in
  the channel and 8 connected users.
• New users may arrive in the Channel at any time.
• Support disconnecting from a connected user.
• Dont worry about supporting more than 8 users.
• Remove users that timeout (more on this later).
• Store and display appropriate console messages
  (use RAM for this).
• Console must display up to 8 lines of 32
  characters each.
• Once console fills up, each new message should
  push the oldest one out.

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Announcements

• Checkpoint 3 is due in two weeks
• Week of 11/12
• Checkpoint 4 is due in four weeks
• Week of 11/26
• Checkpoint 4 design reviews next week.

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Announcements

• Each group should have been assigned a channel
  during lab last week.
• Dont continuously spam your channel.
• Another group is sharing your channel.
• Guaranteed your channel during your lab section.
• Channel assignments will be posted this weekend.

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Announcements

• Clarification for Checkpoint 3
• BigOut and BigIn should be 328 bits (41-bytes),
  not 320 bits (40-bytes).
• An updated version of the checkpoint has been
  uploaded.

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Announcements

• Midterms have been graded
• Pick them up after lab lecture.

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Communications Module

• Responsibilities
• Announce presence every 250 ms.
• Initiate a call with another station.
• Acknowledge a call request.
• Reject a call request.
• Receive audio data.

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Packet Format

• The 41-byte payload from Checkpoint 3 belongs to
  the application layer
• 1-byte header
• 40-byte payload

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Packet Format
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Packet Types

• Announce
• Broadcast (0xFF) an announcement packet
  containing your user name every 250 ms.
• Init Call
• You want to initiate a call request to someone
  specific.
• Ack Init
• Acknowledge that you received an init call
  request, but neither accept nor reject.
• Accept Call
• Accept a call request

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Packet Types

• Reject Call
• Reject a call request
• Data
• Payload contains audio data
• Ready
• Acknowledge an accept call.
• Used to keep an active connection alive when no
  data is being sent.

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Communications Behavior

• Sit idle and receive packets by default.
• Send an Announce packet every 250 ms.
• If received packet is an Announce packet, notify
  Video Display.
• If you initiate a call request, send an Init Call
  packet and wait for acknowledgement.
• Keep exchanging Init Call/Ack Init until one of
  the following happens
• Connection times out.
• Accept Call packet is received, establish chat.
• Reject Call packet is received, return to idle
  state.
• You press Cancel.
• No need to send Announce packets during Init
  Call/Ack Init exchange

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Communications Behavior

• During a call, perform the following
• Receive audio data and Ready packets.
• Reset timeout counter.
• Send audio data whenever it is ready.
• Receive Announce packets and notify Video
  Display.
• Optionally send Ready packets to keep the
  connection alive in the absence of audio data.
• Return to idle receive state if
• Neither audio data nor Ready is received in 1
  second.
• You manually disconnect the call.
• No need to send Announce packets during a call.

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Communications Behavior
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Communications Behavior
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Tips, Hints, Common Pitfalls

• Start early
• If youre already done with CP3, start designing
  now!
• We are not providing skeleton Verilog files
• Run the TA solution to see what the final result
  should look like.

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Tips, Hints, Common Pitfalls

• Split up the checkpoint to work in parallel with
  your partner
• User input parser can be fully tested
  independently without Video Display or
  Communications.
• Video Display can be fully tested with a simple
  user input parser and no Communications.
• Communications module can be fully tested in
  ModelSim without the user input parser or video
  display.
• Do not combine until youve verified each part
  works independently.
• It can take up to 50 minutes to push to board
  after combining!

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Tips, Hints, Common Pitfalls

• Reset is unreliable if N64 controller is
  unplugged (unknown button status is returned).
• Even if N64 controller is plugged in, the user
  input parser may still enter an unpredictable
  state upon Reset.
• Output the current state of the parser somewhere
  and keep resetting until it enters the correct
  state.

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Requirements

• Support persistent two-way communication between
  two stations.
• Need not be compatible with TA solution
• Single bit file
• Latency between speaking into microphone and
  hearing on remote station must be less than 1
  second.

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Extra Credit

• Maximum 20
• Some Ideas (Exact TBD)
• Text messaging
• Talk with more than 1 person simultaneously
• Audio effects (e.g. reverberations)
• Using the console region for a shared game (e.g.
  Pong, Tetris, Guitar Hero)
• Send video
• Record and playback a long conversation using
  SDRAM
• Ring tones
• Open-ended! Come up with something special, cool,
  clever, unique, and/or challenging.

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Stay Tuned

• The spec has not been finalized yet.
• It should be up by later tonight.
• There is enough information in these lecture
  slides to get you started.

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Questions?