CBOLD Reference: TBundle

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C⁺⁺BOLD Reference Manual

4.3. TBundle

TBundle acts like a complex TPort. It is used to provide connectivity between modules. Classes derived from TBundle and instances of such classes are referred to as bundles. TBundle's only user-coded member function is Register(). TBundle is essentially a container for creating sets of ports. Despite its name, a TBundle is not a bus, net, or group of nets. It is more like a complex connector. As an example, consider this DB13W3 connector:

This type of connector integrates three coax and ten individual connections. It was used for analog RGB video monitors. If, for example, your design had a Video subsystem and a FrontPanel subsystem in which a DB13W3 connector was instantiated, the interface between the two subsystems might be expressed as the following bundle:

class CB_Video_FrontPanel : public TBundle {   // Video-to-FrontPanel Interface
public:
  port R;
  port G;
  port B;
  port V_SYNC;
  port C_SYNC;
  port H_SYNC;
//port GND;          // omit ground -- by convention, ground connections are made via a dedicated GND port on each module
  port SENSE_GND;    // but this analog ground is a separate net from GND
  port SENSE;        // AR_BUS(2,0) three analog sense lines
  virtual void Register() {
    ...
  }
};

You would then add a CB_Video_FrontPanel member to each of the subsystems...

class CM_Video : public TModule {        // Video Subsystem
public:
  CB_Video_FrontPanel   FP;              // interface to FrontPanel subsystem
  ...                                    // e.g., interfaces to other subsystems
};
 
class CM_FrontPanel : public TModule {   // FrontPanel Subsystem
public:
  CB_Video_FrontPanel   VI;              // interface to Video subsystem
  ...                                    // e.g., interfaces to other subsystems
};

... and connect the two subsystems at the Root level:

class CM_Root : public TRootModule {     // Root of Hierarchy
  CM_Video       Video;                  // Video      Subsystem
  CM_FrontPanel  FrontPanel;             // FrontPanel Subsystem
  ...
  virtual void Connect() {
    ...
    "VI_" << Video.FP << FrontPanel.VI;  // connect the interfaces between Video and FrontPanel
    ...
  }
};

"VI_" is known as a net prefix. CBOLD uses the prefix to create net names based on the names of bundle members. The single connection statement above results in the creation of the following net names:

VI_R

VI_G

VI_B

VI_V_SYNC

VI_C_SYNC

VI_H_SYNC

VI_SENSE_GND

VI_SENSE0

VI_SENSE1

VI_SENSE2

A TBundle may have member TBundle's as well as member ports:

class CB_Color : public TBundle {
public:
  port R;
  port G;
  port B;
  virtual void Register() {
    ...
  }
};
 
class CB_Sync : public TBundle {
public:
  port V_SYNC;
  port C_SYNC;
  port H_SYNC;
  virtual void Register() {
    ...
  }
};
 
class CB_RGB_Video : public TBundle {
public:
  CB_Color  Color;
  CB_Sync   Sync;
  port      SENSE_GND;
  port      SENSE;        // AR_BUS(2,0) three analog sense lines
  virtual void Register() {
    ...
  }
};

For details on making connections to bundles or members of bundles, see Connections.