Serial Port USB read/write access


I'm trying to use a serial terminal program (moserial) to send serial data from my laptop (running on Ubuntu Mate) to my microcontroller for programming via USB. The help section of moserial recommends I type the following to get read/write permission from my laptop serial ports:

"sudo chmod o+rw /dev/ttyS*" and "sudo chmod o+rw /dev/ttyUSB*"

These commands aren't working for me. I get an error that I'm "missing an operand"

Would you have any advice to allow me access to my USB ports ?

Thanks so much.

read the chmod man page ...

Multiple symbolic modes can be  given,  separated by commas.

your command becomes sudo chmod o+r,o+w /dev/ttyS*

also, add your username to the dialout group