Control of USB modem

[William Murray]

  Hello all,
      I have a USB modem (running eciadsl) for my home connection, with
some scripts I hacked to switch it on at power up and monitor that it is
still working. If it does down (happens every few days) it is restarted 
automatically
However, sometimes it hangs, power on, and does not respond stop
commands. I am trying to work out how to detect failure, and if possible
reset the device. I think a reboot of the whole machine will do the
trick, but is there a less-destructive way?
    Thank you,
        Bill Murray