======================================================================== UHD - Coding to the API ======================================================================== .. contents:: Table of Contents ------------------------------------------------------------------------ Various API interfaces ------------------------------------------------------------------------ ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Low-Level: The device API ^^^^^^^^^^^^^^^^^^^^^^^^^^^ A device is an abstraction for hardware that is connected to the host system. For a USRP, this means that the motherboard and everything on it would be considered to be a "device". The device API provides ways to: * Discover devices that are physical connected to the host system. * Create a device object for a particular physical device identified by address. * Register a device driver into the discovery and factory sub-system. * Streaming samples with metadata into and out of the device. * Set and get properties on the device object. See the documentation in *device.hpp* for reference. ^^^^^^^^^^^^^^^^^^^^^^^^^^^ High-Level: The multi usrp ^^^^^^^^^^^^^^^^^^^^^^^^^^^ The Multi-USRP class provides a FAT interface to a single USRP with one or more channels, or multiple USRPs in a homogeneous setup. See the documentation in *usrp/multi_usrp.hpp* for reference. ------------------------------------------------------------------------ Integrating custom hardware ------------------------------------------------------------------------ Creators of custom hardware can create drivers that use the UHD API. These drivers can be built as dynamically loadable modules that the UHD will load at runtime. For a module to be loaded at runtime, it must be: * found in the UHD_MODULE_PATH environment variable, * installed into the /share/uhd/modules directory, * or installed into /usr/share/uhd/modules directory (unix only). ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Custom motherboard ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Create a new device driver when the driver in lib/usrp/ cannot support your custom FPGA or hardware modifications. Make a copy of the relevant driver code in lib/usrp/, make mods, and rename the class. The new device code should register itself into the discovery and factory system. ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Custom daughterboard ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Use code from an existing daughterboard in lib/usrp/dboard/* as an example. Your daughterboard code should subclass an rx dboard, rx dboard, or xcvr dboard; and it should respond to calls to get and set properties. The new daughterboard code should register itself into the dboard manager with a unique rx and/or tx 16 bit identification number.