[Tinyos-devel] lost packets from PC to the mote

[Philip Levis]

On Apr 18, 2008, at 6:47 PM, Razvan Musaloiu-E. wrote:
> Hi!
>
> I just noticed that when a mote sends a lot of packets to a the PC,  
> the packets from the PC to the mote doesn't go reach the user  
> application layer some of the time. In the attached archive there is  
> a test program that is exposing this. The mote program is sending  
> packets back-to-back while the PC program (in Java) is receiving the  
> packets and sends to the mote one packets each second. I run the  
> program on telosb in the following way:
>
> (console 1)$ ./sf 9001 /dev/ttyUSB0 115200
> (console 2)$ java StressSerialTest -comm sf at localhost:9001
>
> The mote is toggling the blue led each time it receives a packet and  
> it should change state each time the RX led from the USB blinks.  
> This doesn't always happen: the RX led indicates a receive but the  
> blue doesn't always change its state. The (console 1) also shows  
> lines like this:
> 	Note: write failed
> 	Note: write failed
> 	Note: write failed
> 	Note: write failed
>
> Did anyone else notice this behavior?

Razvan,

When I run your test application on my machine, I do not see this  
behavior. I was able to send 100 packets (the program ran for 100  
seconds) with no write fails. What write fail rate do you observe?

I ran your Java application connected to a C serial forwarder.

Phil