http://www.ratatanek.cz/hg/ultrasound_beacon/ en-us ultrasound_beacon Changelog ultrasound_beacon Changelog Switch to using watchdog reset to enter bootloader. http://www.ratatanek.cz/hg/ultrasound_beacon/rev/aaf5f98f3a2f Martin Vejnar <avakar@ratatanek.cz> Fri, 02 Apr 2010 23:08:49 +0200 Updated dependency list for changeset 0dd70531aa4f http://www.ratatanek.cz/hg/ultrasound_beacon/rev/5ee358bf8535 Martin Vejnar <avakar@ratatanek.cz> Thu, 18 Mar 2010 21:10:40 +0100 Initial import. http://www.ratatanek.cz/hg/ultrasound_beacon/rev/0dd70531aa4f
The period if fixed to 16.384ms. Each period the transmitter is
fed with two cycles of a 40kHz rectangular wave.

The wave is sent through PB1 (positive) and PB2 (inverted),
an ultrasound transmitter can be connected directly to these two
pins.

PD6 rises at the beginning of each period and falls when the wave
transmission is finished.]]> Martin Vejnar <avakar@ratatanek.cz> Thu, 18 Mar 2010 21:10:35 +0100