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Function RTUGetEndpoint

RTUGetEndpoint returns a pointer to an endpoint descriptor:

typedef struct { 
   BYTE bLength;              // length in bytes of this descriptor 
   BYTE bDescriptor;          // descriptor ID (5) 
   BYTE bEndPointAddress;     // address and direction 
   BYTE bmAttributes;         // transfer, synch, and usage type 
   WORD wMaxPacketSize;       // max packet size, packets per microframe 
   BYTE bInterval;            // polling interval in [micro]frames 
} RTUEndpointDescriptor; 

const RTUEndpointDescriptor * 
  RTUGetEndpoint(const RTUInterfaceDescriptor * Interface, 
                 int                            Endpoint);

Parameters

Interface

Pointer to an interface descriptor of the interface containing the desired endpoint.

Endpoint

Zero-based index of the endpoint to retrieve. This parameter must be in the range 0 .. RTUInterfaceDescriptor.bNumEndpoints-1.

return value

Pointer to the desired endpoint descriptor or NULL if parameter Endpoint is out of range.

Endpoint descriptors are required by RTUOpenPipe.

Members bEndPointAddress, bmAttributes, wMaxPacketSize, and bInterval contain bit fields and should not be addressed directly. Use functions RTUEndpointDirection, RTUEndpointType, RTUEndpointPacketSize, and RTUEndpointInterval instead.

Further details about the endpoint descriptor are given in the USB specification.

Device Query

Function RTUFindInterface

Function RTUEndpointDirection