Sending, Receiving and Processing Messages NQC Tutorial pp'3436

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Sending, Receiving and Processing MessagesNQC
Tutorial pp.34-36
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Sending and Receiving Messages

• A robot can use the command SendMessage() to send
  a value (0-255) over the infra-red port. All
  other robots receive this message and store it.
• The program in a robot can ask for the value of
  the last message received using Message(). Based
  on this value the program can make the robot
  perform certain actions.

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Master and Slave

• Two cooperating robots can interact
• Master-- sends a message
• Slave-- responds to the message
• In the following example we will develop a
  communication protocol in which we define three
  messages
• 1 go forward,
• 2 go backward, and
• 3 stop.

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task main() // SLAVE while (true) ClearMes
sage() until (Message() ! 0) if (Message()
1) OnFwd(OUT_AOUT_C) if (Message() 2)
OnRev(OUT_AOUT_C) if (Message() 3)
Off(OUT_AOUT_C)
task main() // MASTER SendMessage(1)
Wait(200) SendMessage(2) Wait(200) SendMessag
e(3)
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Messaging Protocol for Nursebot
The message will represent the destination for
nursebot.
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start
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• When your nursebot is started, it should remain
  stationary at the starting point until it
  receives a message detailing the destination.
• At that time it should acknowledge receipt of the
  message by tone sounding. That is, if the
  destination is 4, sound a tone 4 times. (Hints
  use a repeat loop and dont forget to add a
  delay.)