On Fri, Mar 12, 2010 at 6:44 PM, Todd Anderson <taanderson@go.wustl.edu> wrote:
> Hey, I'm trying to get ROS working on the Arduino Mega board using Andrew
> Harris' pmad package for the Arduino board.  Unfortunately his node only
> supports 4 digital pins while the board I'm using has 18.

Hi Todd,

   Actually only the status packet is limited to providing the current
value of 4 digital pins.  The "pmad_switch_control" service is capable
of switching any digital pin.  You just have to provide the argument
that you would use for the Arduino's "digitalWrite" function as the
first argument.  So for example, if you wanted to set digital pin 13's
state to HIGH, you would issue the following:

rosservice call pmad_switch_control 13 1

   I'd be happy to provide another service that could return the
current status of any digital pin if you need it.

regards,
-andrew