Usage of ttyS1

I am trying to connect a RFID reader to a RS232 port (port B, I think is /dev/ttyS1). But when I try to launch the application and it tries to connect via RS232 I get this error:

“execve: No such file or directory”

Any idea if I am misconfiguring something or I am doing something wrong?

try /dev/ttyS2

Obviously I did… I solve it, it is /dev/ttyNS1

ttyNS1 is only a link to ttyS1

/ # cd dev
/dev # ls -l tty*
crw-rw---- 1 root root 5, 0 Jan 1 00:00 tty
lrwxrwxrwx 1 root root 5 Jan 1 00:00 ttyNS1 -> ttyS1
lrwxrwxrwx 1 root root 5 Jan 1 00:00 ttyNS2 -> ttyS2
lrwxrwxrwx 1 root root 5 Jan 1 00:00 ttyNS3 -> ttyS3
crw-rw---- 1 root root 204, 197 Jan 1 00:00 ttyS1
crw-rw---- 1 root root 204, 198 Jan 1 00:00 ttyS2
crw-rw---- 1 root root 204, 199 Jan 1 00:00 ttyS3