USB
 
General Info
Properties
Methods
Events
Typical Usage



Types & definitions
Component Index
CPU Component Index
Embedded Components
Components Categories



Component icon
Component USB
USB device bean
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 - Name of the component
  • USB module - USB module
  • Supported languages - 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).
  • Interrupt service/event - Component uses the interrupt service for communication.
    The following items are available only if the group is enabled (the value is "Enabled"):
  • Device description - Device description contains details information about the USB device which is connected to a USB bus by this component.
    • External power source - Specifies if the device has external power source.
    • Class code - Class code (assigned by the USB standard). If this field is zero, each interface within a configuration specifies its own class information and the various interfaces operate independently. If this field is 0xFFh, the device class is vendor specific. Other values of this field (0x01h - 0xFEh) identifies the class definition used for the aggregate interfaces.
    • Subclass code - Subclass code assigned by the USB standard. These codes are qualified by the value of the Class code field. If the Class code is zero this field must also be zero. If the Class code is not set to 0xFFh, all values are reserved for assignment by the USB standard.
    • Protocol code - This code is qualified by the value of the Class code and Subclass code. If this device support class-specific protocols on the device basis, this code identifies the protocol that the device uses. If this field is zero, the device does not use class-specific protocols on the device basis. However, it may use class-specific protocols on an interface basis. If this field is set to 0xFFh, the device uses a vendor-specific protocol on a device basis.
    • Max EP0 packet size - Specify the size of EP0 buffer (for information only).
    • Vendor ID - Vendor identification number.
    • Product ID - Product identification number.
    • Device release number - Device release number in BCD.
    • Manufacturer description - Unicode string describing this device.
    • Product description - Unicode string describing this product.
    • Device's serial number - Unicode string with device serial number.
  • Configuration descriptor list - List of configuration descriptors used by this device. Click '+' to add new configuration descriptor.
    One Item of the list looks like:
    Configuration1 - Configuration descriptor settings.
    • Number of interfaces - Number of interfaces in this configuration (for information only).
    • Configuration value - This value is used as an argument for the SetConfiguration() request to select this configuration (for information only).
    • Configuration descripton - Unicode string describing this configuration.
    • Power characteristics - Power characteristic of the device in this configuration. The device can be supplied by the bus or by the external power source. (Note: For a device without external power source you cannot select 'self powered' option.)

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

    • Remote wakeup - Specify if the device supports remote wakeup.

      There are 2 options:
      • yes: Device supports remove wake up.
      • no: Device does not support remove wake up.

    • Maximum power consumption [2mA units] - This field specify maximum power consumption from the bus [expressed in 2mA units] when the device is fully operational.
    • Interface descriptor list - List of interface descriptors used by this configuration. Click '+' to add new interface descriptor.
      One Item of the list looks like:
      Interface 0 - Interface descriptor settings.
      • Alternate setting list - List of alternate interface descriptors used by this interface. Click '+' to add new alternate interface descriptor.
        One Item of the list looks like:
        Alternate setting 0 - Interface descriptor settings.
        • Interface number - Number of interface. Zero-based value identifying the index in the array of concurrent interfaces supported by this configuration (for information only).
        • Alternate setting - Value used to select alternate setting for the interface identified in the prior field (for information only).
        • Number of endpoints - Number of endpoints used by this interface (excluding endpoint zero). If this value is zero, this interface only uses the Default Control Pipe (for information only).
        • Class code - Class code of the interface. A value of zero is reserved. If this field is set to 0xFFh, the interface class is vendor specific. All other values are reserved for assignment by USB standard.
        • Subclass code - This code is qualified by the value of the Class code. If the Class code is zero this code must also be reset to zero. If the Class code is not set to 0xFFh, all values are reserved for assignment by the USB standard.
        • Protocol code - This code is qualified by the value of the Class code and Subclass code. If this interface support class-specific request, this code identifies the protocol that the device uses as defined by the specification of the device class. If this field is zero, the device does not use class-specific protocols on the interface. If this field is set to 0xFFh, the device uses a vendor-specific protocol for this interface.
        • Interface description - Unicode string describing this interface.
        • Pipe list - List of pipes used by this interface alternate setting. Click '+' to add new pipe.
          One Item of the list looks like:
          Pipe 0 - A USB pipe is an association between an endpoint on a device and software on the host.
          An endpoint is a uniquely identifiable portion of a USB device that is the terminus of a communication
          flow between the host and device. device. Each USB logical device is composed of a collection of independent endpoints. Each logical device has a unique address assigned by the system at device attachment time. Each endpoint on a device is given at design time a unique device-determined identifier called the endpoint number. Each endpoint has a device-determined direction of data flow. The combination of the device address, endpoint number, and direction allows each endpoint to be uniquely referenced. Each endpoint is a simplex connection that supports data flow in one direction: either input (from device to host) or output (from host to device).
          • Endpoint number - Generally a four-bit value between 0x00H and 0xFH, inclusive, associated with an endpoint on a USB device. Endpoint number 0 is reserved for the Default Control Pipe.
            Admissible range is HW dependent.
          • Direction - The direction of data transfer on the USB. The direction can be either IN or OUT. IN refers to transfers to the host; OUT refers to transfers from the host.
            Admissible values are HW dependent.

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

          • Transfer type - Determines the characteristics of the data flow between a software client and its function (a USB device that provides a capability to the host). Four transfer types are defined: control, interrupt, bulk, and isochronous.
            Control transfers support configuration/command/status type communications between client and function.
            Interrupt transfer characteristics are small data, non-periodic, low-frequency, and bounded-latency. Interrupt transfers are typically used to handle service needs.
            Bulk transfers are non-periodic, large bursty communication typically used for a transfer that can use any available bandwidth and can also be delayed until bandwidth is available.
            Isochronous transfers are used when working with isochronous data. Isochronous transfers provide periodic, continuous communication between host and device.
            Admissible values are HW dependent.

            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 (this value is HW dependant).

            There are 9 options:
            • 8: Size of endpoint buffer
            • 16: Size of endpoint buffer
            • 32: Size of endpoint buffer
            • 64: Size of endpoint buffer
            • 128: Size of endpoint buffer
            • 256: Size of endpoint buffer
            • 512: Size of endpoint buffer
            • 1023: Size of endpoint buffer
            • 1024: Size of endpoint buffer

          • 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.
  • USB system timer - Settings supported for HC908DB48, HC908JB8, HC908JB12, HC908JB16 and HC908JG16 derivatives only.
  • USB pins
  • USB reset signal options - Settings supported for HC908JB8, HC908JB12, HC908JB16, HC908JG16 and HC908JR32 derivatives only.
    • USB reset signal result - Specify what to do if USB reset signal is detected. (Possible values are "USB interrupt request" and "MCU reset")

      There are 2 options:
      • USB interrupt request: USB reset causes interrupt request.
      • MCU reset: USB reset causes MCU reset.

  • Compound device properties - Settings supported for HC908LD64 only.
  • Initialization - Initial settings (after power-on or reset).
    • Enabled in init. code - The component is enabled after power-on or reset (in initialization code). This property is not used with MC68HC908LD64 (Compound device is initialized by the host request only).
    • Events enabled in init. - Events enabled in initialization.
  • 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.

PROCESSOR EXPERT is trademark of Freescale Semiconductor, Inc.
Copyright 1997 - 2010 Freescale Semiconductor, Inc.