Resetting USB ports via Terminal

So I've made a stupid mistake by messing around with Terminal trying to fix a dodgy USB stick. I entered some commands such as "diskutil eraseDisk HFS+ newdisk disk2" trying a few different options without fully understanding what I was doing. Now anything I plug into either USB 3.0 ports gets the message "The disk you inserted was not readable by this computer". USB drives and hard drives that worked before now no longer work.

I've tried resetting SMC and PRAM to no avail. Would rather not format the whole system as I can't do a more recent backup to HDD beforehand now. But if it comes to it, will this fix the problem?

Can someone tell me what commands to enter into terminal to set these ports back to what they were before I started messing with it?