A command hold-reset will put the state of modem into reset mode
until an inverse command to bring modem out of RESET mode.
During the period of reset mode, this modem can not be used
and is non-functional.
This object is only valid when cmState is onHook, busiedOut, or
disabled. The value of true(1) attempts to put the modem in
reset mode, and the value of false(2) takes the modem out of
reset.
This object is not applicable for Mica modems.