USBTrace : Class Decoding : Communication Device (CDC)

USB devices which belong to the Communication Device class can be monitored using the Communication Device class decoder (Plug-in dll). The devices which fall in to this category include telecommunication devices (analog modems, ISDN terminal adapters, digital telephones, and analog telephones) & networking devices (ADSL modems, cable modems, 10BASE-T Ethernet adapters/hubs, and “Ethernet” cross-over cables).

The decoder will capture, decode and display CDC class specific functional descriptors, communication class interface management element requests and management element notifications.

The following class specific functional descriptors are decoded:

• Video Control (VC) Requests
• Header Functional Descriptor
• Union Functional Descriptor
• Country Selection Functional Descriptor
• Call Management Functional Descriptor
• Abstract Control Management Functional Descriptor
• Direct Line Management Functional Descriptor
• Telephone Ringer Functional Descriptor
• Telephone Call Functional Descriptor
• Telephone Operational Modes Functional Descriptor
• USB Terminal Functional Descriptor
• Network Channel Terminal Functional Descriptor
• Protocol Unit Functional Descriptor
• Extension Unit Functional Descriptor
• Multi Channel Management Functional Descriptor
• CAPI Control Management Functional Descriptor
• Ethernet Networking Functional Descriptor
• ATM Networking Functional Descriptor
• WHCM Functional Descriptor
• Device Management Model Functional Descriptor
• OBEX Functional Descriptor
• Command Set Functional Descriptor
• Command Set Detail Functional Descriptor
• Telephone Control Model Functional Descriptor

The following communication interface management element requests are decoded:

• Set Comm Feature (SET_COMM_FEATURE)
• Get Comm Feature (GET_COMM_FEATURE)
• Clear Comm Feature (CLEAR_COMM_FEATURE)
• Set Aux Line State (SET_AUX_LINE_STATE)
• Set Hook State (SET_HOOK_STATE)
• Pulse Setup (PULSE_SETUP)
• Send Pulse (SEND_PULSE)
• Set Pulse Time (SET_PULSE_TIME)
• Ring Aux Jack (RING_AUX_JACK)
• Set Line Coding (SET_LINE_CODING)
• Get Line Coding (GET_LINE_CODING)
• Set Control Line State (SET_CONTROL_LINE_STATE)
• Send Break (SEND_BREAK)
• Set Ringer Parms (SET_RINGER_PARMS)
• Get Ringer Parms (GET_RINGER_PARMS)
• Set Operation Parms (SET_OPERATION_PARMS)
• Get Operation Parms (GET_OPERATION_PARMS)
• Set Line Parms (SET_LINE_PARMS)
• Get Line Parms (GET_LINE_PARMS)
• Dial Digits (DIAL_DIGITS)
• Set Unit Parameter (SET_UNIT_PARAMETER)
• Get Unit Parameter (GET_UNIT_PARAMETER)
• Clear Unit Parameter (CLEAR_UNIT_PARAMETER)
• Get Profile (GET_PROFILE)
• Set Ethernet Power Management Pattern Filter (SET_ETHERNET_POWER_MANAGEMENT_PATTERN_FILTER)
• Get Ethernet Power Management Pattern Filter (GET_ETHERNET_POWER_MANAGEMENT_PATTERN_FILTER)
• Set Ethernet Multicast Filters (SET_ETHERNET_MULTICAST_FILTERS)
• Set Ethernet Packet Filter (SET_ETHERNET_PACKET_FILTER)
• Get Ethernet Statistic (GET_ETHERNET_STATISTIC)
• Set ATM Data Format (SET_ATM_DATA_FORMAT)
• Get ATM Device Statistics (GET_ATM_DEVICE_STATISTICS)
• Set ATM Default VC (SET_ATM_DEFAULT_VC)
• Get ATM VC Statistics (GET_ATM_VC_STATISTICS)

The following communication interface management element notifications are decoded:

• Network Connection (NETWORK_CONNECTION)
• Response Available (RESPONSE_AVAILABLE)
• Connection Speed Change (CONNECTION_SPEED_CHANGE)
• Aux Jack Hook State (AUX_JACK_HOOK_STATE)
• Ring Detect (RING_DETECT)
• Serial State (SERIAL_STATE)
• Call State Change (CALL_STATE_CHANGE)
• Line State Change (LINE_STATE_CHANGE)

Image below shows a CDC request packet, decoded and displayed by USBTrace.