Linking between px4 SITL and MAVROS

[SAI_RAGHAVENDRA_MUPP (Sai Raghavendra Muppavaram)]

while trying to use roslaunch
roslaunch mavros px4.launch fcu_url:="udp://:14540@127.0.0.1:14557"

Iam getting this error please help me out

[james_pattison]

For help with px4, better to ask at discuss.px4.io