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RL-ARM User's Guide (MDK v4)

RL-RTX RL-FlashFS RL-TCPnet RL-CAN RL-USB RL-USB for USB Device Applications RL-USB Device Library RL-USB Device Features RL-USB Device Software Stack RL-USB Device Functions RL-USB Device Source Files RL-USB Device Configuration Audio Device (ADC) Options Communication Device (CDC) - ACM Options Human Interface Device (HID) Options Mass Storage Device (MSC) Options Create USB Device Applications Create ADC Applications Create CDC ACM Applications Create HID Applications Create MSC Applications Create Composite Applications Test USB Device Applications Compliance Tests Test HID Client Application RL-USB for USB Host Applications RL-USB Host Library RL-USB Host Features RL-USB Host Software Stack RL-USB Host Functions RL-USB Host Source Files RL-USB Host Configuration Host Controller Driver Selection Host Controller Driver Configuration Host Class Driver Selection Create USB Host Applications Create USB Host HID Applications HID_Kbd Example Create USB Host MSC Applications Create USB Host Class Driver RL-USB Host Constants and Structures Error constants Speed constants Transaction Packet Type constants Transaction Error Type constants USB Request Block structure (USBH_URB) Endpoint structure (USBH_EP) Driver Capabilites structure (USBH_HCI_CAP) Device Class Instance structure (USBH_DCI) Host Controller Instance structure (USBH_HCI) Host Controller Driver structure (USBH_HCD) USB Concepts USB Transfer Rates USB Network Basic Communication Model USB Protocol Control Transfer Interrupt Transfer Isochronous Transfer Bulk Transfer Descriptors Device Configuration Device Descriptor Configuration Descriptor Interface Descriptor Endpoint Descriptor Device Qualifier Descriptor Example Programs Library Reference Appendix

Driver Capabilites structure (USBH_HCI_CAP)

Host Controller driver Instance CAPabilities (USBH_HCI_CAP) structure represents host controller driver instance capabilities.

typedef struct {                        /* Host Controller Driver Capabilities*/
  union {
    struct {
      U32      MultiPckt;               /* Multiple data packet handling      */
  U32          MaxDataSz;               /* Maximum data that can be handled   */
  U32          CtrlNAKs;                /* Number of NAKs for ctrl endpoints  */
  U32          BulkNAKs;                /* Number of NAKs for bulk endpoints  */

Explanation of USBH_HCI_CAP structure elements:

  • MultiPckt determines if driver supports multiple packets in a single transfer request. (__TRUE = supports multiple packet transfers, __FALSE = no support for multiple packet transfers)
  • MaxDataSz represents maximum data that can be handled by driver.
  • CtrlNAKs represents number of NAKs that driver will wait for transfer on control endpoint before reporting that transfer has failed.
  • BulkNAKs represents number of NAKs that driver will wait for transfer on bulk endpoint before reporting that transfer has failed.
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