Thank you Nickolay but I don't know how can I configure? That link has very general explanation and I have installed all those packages and also installed sphanix-base and pocketsphinx again, but that error comes again.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
I have a board similar to raspberry pi(nani pi-m1) and have installed ubuntu-core 1604. but get this error:
I have searched and tried some suggestions but didn't work for me!
I most also say my board has an on-board microphone and I have installed and tested pocketsphinx before with Jessie 8.5 on this board succesfully.
This error usually means pulseaudio not configured properly. For more details read
https://cmusphinx.github.io/wiki/faq/#q-failed-to-open-audio-devicedevdsp-no-such-file-or-directory
Thank you Nickolay but I don't know how can I configure? That link has very general explanation and I have installed all those packages and also installed sphanix-base and pocketsphinx again, but that error comes again.
This is not pocketsphinx issue, you can ask on Ubuntu forums or Raspberry Pi forums.