Waiting for heartbeat from /dev/ttyAMA0

Hi,
i am trying to connect raspberry pi b to my pixhawk at telem 2 port with the GPIO pins of the raspberry pi as shown in dev.ardupilot.com/wiki/raspberry-pi-via-mavlink/ post.
i have also changed the pixhawk parameters as in viewtopic.php?f=21&t=8798#p20733
but when i enter " mavproxy.py --master=/dev/ttyAMA0 --baudrate 115200 --aircraft MyCopter" in the pi terminal
i always get
"Connect /dev/ttyAMA0 source_system=255
no script MyCopter/mavinit.scr
Log Directory: MyCopter/logs/2015-12-14/flight5
Telemetry log: MyCopter/logs/2015-12-14/flight5/flight.tlog
MAV> Waiting for heartbeat from /dev/ttyAMA0"
i think either i am missing some setting in the pixhawk for which its not sending the heartbeat signals a to raspberry pi.
** i ran the Sitl on my mac and was able to connect with the mavproxy of the pi"
If i am missing something please point me in the right direction as to how i can set up the connection between the pi and pixhawk

Thanks.

I too am having this same problem. Have you found a solution yet?