Hi, I have a problem with an TIMER and the function NAFSopen_file. I have a TIMER installed, with this TIMER I call a subroutine. This subroutine open a file and write measuring values in the open file. This do not work, I get an error message returned from the function NAFSio_request_cb_status -> "NAFS_IO_REQUEST_PENDING". Without the TIMER my program is working correctly. Can someone help me, what is the cause of the problem?