Lots of Squares on the Serial Readout

my code simple receiver , rebroadcaster 802.15.4 protocol.

 void setup(){
 }
  void loop(){
   char c = serial.read();
   serial.print(c);
 }

we have more complicated transmitter , had communication working before whenever connect them serial output used write square (characters) really fast until crashed.  i reinstalled arduino , writes squares slower doesn't write correct information.

any ideas squares in serial means?

it means bit rates aren't matched.
you haven't shown initialisation of serial object.

Arduino Forum > Forum 2005-2010 (read only) > Software > Interfacing > Lots of Squares on the Serial Readout

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