USBHUB
 
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Component icon
Component USBHUB
USB HUB device
Component Level: High
Category: CPU Internal Peripherals-Communication
Properties:
(Properties are parameters of the component. Please see the Embedded Components page for more information.)
  • Component name - Component name
  • HUB module - USB module
  • Hub Interrupt service/event - Component uses the interrupt service for communication. If enabled, the component functionality (e.g. sending and receiving data) depends on the interrupt service and will not operate if the CPU interrupts are disabled. For details please refer to chapter "interrupt service in the component's generated code".
    The following items are available only if the group is enabled (the value is "Enabled"):
  • SupLangs - List of languages supported by this device.
    One Item of the list looks like:
    Language0 - Language ID (Language 0 is default if language requested by OS is not supported).
  • USB Specification Release Number - USB specification release number (for information only).
  • Hub description - Hub description contains detail information about the USB hub connected to the USB bus by this component.
  • Configuration descriptor list - Configurations descriptions
    One Item of the list looks like:
    Configuration1 - Configuration settings
    • Configuration descriptor - Unicode string describing this configuration.
    • Power characteristics - Power characteristic of the device in this configuration. The device can be supplied by the bus or the device is self powered.

      There are 2 options:
      • bus powered: Device is powered from the USB bus
      • self powered: Device has its own power source.

    • Maximum power consumption - This field determines maximum power consumption [mA] if the device is supplied by the bus.
    • Interface 0 - Interface settings.
      • Interface description - Unicode string describing this interface.
      • Endpoint - Endpoint settings.
        • Direction - Direction, ignored for control endpoints.

          There are 2 options:
          • IN: Device to host direction.
          • OUT: Host to device direction.

        • Endpoint address - The endpoint number.
        • Endpoint type - Type of the endpoint. The type can be Control, Interrupt, Bulk or Isochronous.

          There are 4 options:
          • Control: Control transfer type.
          • Isochronous: Isochronous transfer type.
          • Bulk: Bulk transfer type.
          • Interrupt: Interrupt transfer type.

        • Maximum packet size - Maximum packet size this endpoint is capable of sending or receiving. For isochronous endpoints this value is used to reserve the bus time in the schedule, required for the per-frame data payloads (for information only).
        • Polling interval - Interval for pooling endpoint for data transfers. Expressed in milliseconds. This field is ignored for Bulk and Control endpoints. For Isochronous endpoints this field must be 1. For interrupt endpoints, this field may range from 1 to 255 for full speed devices and from 10 to 255 for low speed devices.
  • Hub properties - Various information used to create hub descriptor
    • External power source - Specifies if the hub has external power source.
    • Power switch - Specifies if the hub has power switch.
    • Over-current protection - Specifies if the hub has over-current protection.
    • Logical power switching mode - Specifies logical power switching mode.

      There are 3 options:
      • Ganged power switching: All ports’ power at once.
      • Individual port power switching: Each port power individualy.
      • Reserved - no power switching: Used only on 1.0 compliant hubs that implement no power switching.

    • Over-current protection mode - Specifies over-current protection mode.

      There are 3 options:
      • Global Over-current Protection: The hub reports over-current as a summation of all
      • Individual Port Over-current Protection: The hub reports over-current on per-port basis.
      • No Over-current Protection: This option is allowed only for bus-powered hubs that do not implement over-current protection.

    • Embedded device - This property is automatically set to 'yes' if there is USB bean using embedded device on this chip. After removing USB bean you must set this property to 'no'.

      There are 2 options:
      • yes: Hub is part of a compound device
      • no: Hub is not part of a compound device

    • bPwrOn2PwrGood - Time (in 2ms intervals) from the time the power-on sequence begins on a port until power is good on that port. The USB System Software uses this value to determine how long to wait before accessing a powered-on port.
    • Max. hub controller current - Maximum current requirements of the Hub Controller.
  • HUB upstream port - HUB upstream port setting.
  • HUB downstream port list - List of downstream port of this hub.
    One Item of the list looks like:
    Port1 - Downstream port setting
  • Initialization - Initial settings (after power-on or reset).
  • CPU clock/speed selection - Settings for the CPU speed modes: if the component is supported or not.
    For details about speed modes please refer to page Speed Modes Support.

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