[Tinyos-devel] again about the baudrate issue for telos

Razvan Musaloiu-E. razvanm at cs.jhu.edu
Wed Feb 18 13:38:30 PST 2009


On Tue, 17 Feb 2009, Philip Levis wrote:

> ...
> However, the issue here is not really reliability, but starvation.
> High load in the mote->PC direction causes bytes to be dropped in the
> PC->mote direction, such that packets almost never arrive successfully.
> That being said, there are lots of ways to solve this. Here's a simple
> one: when a packet is lost in the PC->mote direction, have the PC
> toolchain start inserting small pauses between bytes, so the mote has
> time enough to handle the interrupt. Scale the duration of these
> pauses using MIAD (multiplicative increase, additive decrease). This
> would be a few tens of lines of Java code, and would not limit the
> mote->PC rate in the unidirectional case.

Adding a small delay between the bytes solves the problem in the last test 
program I sent. I committed a fix for tos.py. :-)

Razvan ME

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