c1751(config-voiceport)#?
Voice-port configuration commands:
  battery-reversal     Enable FXO battery-reversal detection
  bearer-cap           Specify the bear capability
  busyout              Configure busyout trigger event & procedure
  comfort-noise        Use fill-silence option
  connection           Specify Trunking Parameters
  cptone               Configure voice call progress tone locale
  default              Set a command to its defaults
  description          Description of what this port is connected to
  dial-type            Configure type of dialer for voice
  disc_pi_off          close voice path when disconnect with PI received
  echo-cancel          Echo-cancellation option
  exit                 Exit from voice-port configuration mode
  impedance            Specifies the terminating impedance of the interface
  input                Configure input gain for voice
  music-threshold      Threshold for Music on Hold
  no                   Negate a command or set its defaults
  non-linear           Use non-linear processing during echo cancellation
  output               Configure output attenuation for voice
  playout-delay        Configure voice playout delay buffer
  pre-dial-delay       FXO Pre-dial Delay
  ring                 Number of rings
  shutdown             Take voice-port offline
  signal               The signaling type for the interface FXS or FXO
  snmp                 Modify SNMP voice port parameters
  station-id           Configure station ID
  supervisory          Configure answer + disconnect supervision options
  threshold            Threshold [noise] for voice port
  timeouts             Configure voice timeout parameters
  timing               Configure voice timing parameters
  translate            Translation rule
  translation-profile  Translation profile
  trunk-group          Configure interface to be in a trunk group
  voice-class          Set voiceport voice class control parameters