Boomerang Change UART Baud Rate

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Problem

You want to increase the default UART baud rate that Tmote Sky uses to communicate with the PC.

Or, TOSBase hangs under heavy load, and increasing the default UART baud rate may help. "Heavy load" probably occurs at UART saturation -- when data is received over the radio faster than it can be communicated over the UART. A few people have investigated the problem but can't really nail down the precise condition that causes the failure, so the issue remains.

Work-around

Increase the default baud rate.

  1. Compile TOSBase for another baud rate using the "baud" make extra. For instance, you can compile and install TOSBase for 262144 baud like this:
    make tmote baud,262144 install,1
  2. Set your TOS_PLATFORMS environment variable to specify the file used by Serial Forwarder to override the default serial port specifications for the various platforms
    export TOS_PLATFORMS="`cygpath -m $HOME`/.platform.properties"
  3. To automatically generate the $TOS_PLATFORMS file if it does not yet exist, run Serial Forwarder once then quit
    java net.tinyos.sf.SerialForwarder -no-gui
    # Hit CTRL-C
  4. Edit the $TOS_PLATFORMS file and change the baud rate for tmote to your new baud rate, for instance 262144
    tmote=telos,2,262144
  5. Run serial forwarder as normal, specifying the tmote platform to use the new baud rate