[Tinyos-help]: SoS SoS SoS.... How to transmit data with high speed via serial and WSN??

[Renee Azhen]

Dear all, 
   
  What I want to do is transmitting video from a pc to another pc over the WSN, then play the video on the latter PC with real time.
   
  my Video rates is 40Kbps, So it needs to keep a high transmitting rate for real time playing. My telosb baud rate is 115200 and the WSN transmit data rate is 250Kbps which can meet my needs in theory.
   
  I made a little modification to the apps\BaseStation application to accommodate my need, but found it can't transit data with a high speed, the core code that get data from the serial and transmit to the radio is the following function:
    event message_t *UartReceive.receive[am_id_t id](message_t *msg,
         void *payload,
         uint8_t len) {
   // some code here
   
     if (!radioBusy)
     {
       radioBusy = TRUE;     
       post radioSendTask();
     }
  
  // some code here 
    return ret;
  }
   
  if I set the PC send  rates 100 messages/sec, actually the application can only receive messages 1 times/sec, but if I comment the code
         //post radioSendTask();
  the data can be received about 100 messages/sec, So I suppose the key blocking issue is that the serial will reject to receive new message until the post radioSendTask() is ended.
   
  So here I really lost and don't know how to resolve this problem, how to write the code to make it can send and transfer message more quickly with high speed.
   
  Could any kind guy give me some advice or apps demo or web link to help me.
   
  really  really really really really really  thanks
  The painful and losed Sam
  SoS SoS SoS

 		
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