Device Architecture

Overview

A abstract device proxy class defines the interface detail below. Implementations of this class are used to communicate with a device, either physical or virtual over various mediums.

Members

• int connect(): tells the proxy to connect to the device

  • return: 0 on success, nonzero on error (implementation dependent)

• void disconnect(): tells the proxy to disconnect from the device

• void reset(): tells the proxy to reset the device

• bool is_connected(): tests if device is still connected, will be called frequently to detect disconnects

• int control_request(const usb_ctrlrequest* request, int nbytes, __u8 dataptr): for setup requests, here the data could be in or out depending on the request

  • request: the actual request header
  • nbytes: used to return the actual bytes returned for an OUT (to host) transaction
  • dataptr: buffer for extra data coming in, or to place returned data
  • return: 0 on success, nonzero on error (implementation dependent)

• void send_data(__u8 endpoint,__u8* dataptr,int length): sends data to device on a non zero EP

  • endpoint: endpoint to transmit to
  • dataptr: data to send
  • length: size of data

• void receive_data(__u8 endpoint,__u8** dataptr, int* length): receives data from device on a non zero EP

  • endpoint: endpoint to transmit to
  • dataptr: data received, caller must free
  • length: size of data

• __u8 get_address(): get address of device

• char* toString(): returns a description of the device

examples(that people would use or would be included as examples or whatever)

• physical device via libusb
• tcp/ip interface
• device emulated by BBB
• facedancer emulation (i think the simplest way to handle this at a reasonable level of abstraction, is to write a interface that matches the MAXUSBApp class in the facedancer code, this could run either directly on the BBB or talk to the TCP/IP interface above)