Cannot find "Isusb"

While attempting to upgrade the firmware on Arduino Uno R3 (16U2) the instructions refer to using "Isusb" to verify information. Where can I find this code? I cannot find it by searching Google.



The very first hit when doing a Google search for lsusb:

lsusb(8): USB devices - Linux man page lsusb is a utility for displaying information about USB buses in the system and the devices connected to them.

It's a Linux utility. The instructions (that you did not provide a pointer to) seem to assume you are using a Linux operating system.