My apologies. I really needed to clarify my problem. So I have this setup: My PC(my device) is connected to one end of an RS232 cable. The other end of the RS232 cable is connected to a R232 to USB adapter. Finally, the USB end is connected to my Raspberry Pi 3. So I enabled remote access to my Raspberry pi 3 via SSH. I followed the link: http://www.instructables.com/id/Read-and-write-from-serial-port-with-Raspberry-Pi/. So based on that link, I know that /dev/ttyUSB0 is for my Rpi 3 so I want to read whatever the PC is writing(which is at /dev/ttyAMA0). I wanted to know, to write something from the computer to the rpi3, do I just open another putty terminal so that I can see my rpi3 reading the com1 port of my pc?