Indicates the current state of modem. The meaning of each state code is explained below: unknown: the current state of the modem is unknown. onHook: the condition similar to hanging up a telephone receiver. The call cannot enter a connected state when the modem is onHook. offHook: The condition similar to picking up a telephone receiver to dial or answer a call. connected: The modem is in a state when it can transmit or receive data over the communications line. busiedOut: The modem is busied out (i.e. taken out of service) and cannot make outgoing calls or receive incoming calls. disabled: The modem is in a reset state and non-functional. This state can be set and clear via cmHoldReset. bad: The modem is suspected or proven to be bad. The operator can take the modem out of service and mark the modem as 'bad' via cmBad. loopback: The modem is in a state where it is currently running back-to-back loopback testing. downloadFirmware: The modem is in a state where it is currently downloading the firmware. downloadFirmwareFailed: The modem is not operational because the downloading of firmware to it has failed.