Error Connecting to um7-Sensor

edit

Hi,

I installed ROS indigo and the imu7 package. After connecting my um7-Sensor and enabling UART, I run

roscore

and

rosrun um7 um7_driver _port:=/dev/ttyS0

on my Raspberry Pi 3 in two different terminals. Now I get error looking like:

Timed out waiting for packet from device

and

Unable to set CREG_COM_SETTINGS

The funny thing with this is, that I get this error no matter if the um7 is connected to my Raspberry or not.

Can someone help out? I guess this is a setting problem.

Update:

Meanwhile the error has changed. The problem was that I connected my sensor wrongly (swapped tx/rx connections). Now the error looks like this:

rosrun um7 um7_driver _port:=/dev/ttyS0
[ INFO] [1530260971.555390457]: um7_driver successfully connected to serial port /dev/ttyS0.
[ INFO] [1530260971.585594582]: Received packet 02 without data.
[ INFO] [1530260971.592516347]: Setting update rate to 200Hz
[ INFO] [1530260971.604153387]: Received packet 02 without data.
[ INFO] [1530260971.755901299]: Received packet 04 without data.
[ INFO] [1530260971.907765251]: Received packet 05 without data.
[ INFO] [1530260972.059785349]: Received packet 06 without data.
[ INFO] [1530260972.078310769]: Received packet 08 without data.
[ INFO] [1530260972.084691810]: Sending command: zero gyroscopes
[ERROR] [1530260972.769730627]: Command to device failed.
[ INFO] [1530260972.769994166]: Attempting reconnection after error.