gpsd blocks ttyUSB0 while using ttyACM0 on raspi

[Andreas Heertsch]

Hi

If I run gpsd on Raspi 3B (Buster): /usr/sbin/gpsd -n -b /dev/ttyACM0 (or /dev/ttyS0)

It stops communication on /dev/ttyUSB0:

Unable to open /dev/ttyUSB0 - Device or resource busy

If I shut down gpsd the USB-port /dev/ttyUSB0 works as expected.

(But with the same configuration on Ubuntu and Notebook gpsd does not block the access to /dev/ttyUSB0)

Can I do something better?

Thanks Andreas