Ruby-VPI

Version 18.0.0 released

Tue, 31 Jul 2007 00:00:00 PDT

Version 18.0.0 (2007-07-31)

This release restores support for Synopsys VCS and Cadence NC-Sim, improves portability and performance, and enhances the VPI abstraction layer.

Thanks

Calvin Wong discovered how to bypass the following error emitted by Synopsys VCS when loading the Ruby-VPI shared object file.
```
  Could not open library specified in -load option obj/vcs
  obj/vcs: undefined symbol: vpi_put_data
  
```

Caution

SWIG is now required in order to compile and install Ruby-VPI.

Vpi::Handle.put_value no longer checks whether the value written matches the value read back after writing because that only works when there is no VPI delay associated with the write.

When Vpi::Handle.put_value is used to write a value to a wire (VpiNet), it now forces the value. This is done to ensure portability:
Synopsys VCS and Cadence NC-Sim forget the value written to a wire during the next simulation time step, whereas Mentor Modelsim and GPL Cver remember the value (thereby treating wires as registers).

Note that you have to release a forced value (using Vpi::Handle.release_value) on a wire after writing to the wire if you want the design under test have the ability to update the value of the wire later on:
```
  your_wire.intVal = 15
  your_wire.release_value
  advance_time # let the Verilog DUT modify your_wire
  
```
In addition, you can check if a wire has a forced value using the Vpi::Handle.value_forced? method.

If the format is not specified, Vpi::Handle.get_value now assumes that you want to read the value in VpiIntVal format (because this is the most common case).

The definition of “Derivatives” has been reworded for clarity in the project license.

Repairs

Synopsys VCS and Cadence NC-Sim simulators now correctly load Ruby-VPI. Also, the 64-bit versions of these simulators are now supported.

Improvements

Added “force_value”, “release_value”, and “value_forced?” methods to the Vpi::Handle class.

Vpi::Handle.put_value now tries to automatically detect the format of the value to be written. As a result, you can now write your_handle.put_value 35 in lieu of writing your_handle.intVal = 35.

Vpi::Handle.inspect now shows the hexStrVal of the handle (because it is a common case to want to see a handle’s logic value along with its other information).

Added method caching (memoizing) for VPI property accesses on handles.

Version 17.0.0 released

Sun, 22 Jul 2007 00:00:00 PDT

Version 17.0.0 (2007-07-22)

This release makes the Ruby-VPI testing framework more lightweight by reducing the number of files and parameters involved.

Caution

The generate_test.rb and convert.rb executables have been replaced by a single ruby-vpi executable to avoid name conflicts with other software. They are now accessed using the
```
ruby-vpi generate
```
and
```
ruby-vpi convert
```
commands respectively.

The --name parameter has been removed from the automated test generator. Similarly, you can no longer insert an arbitrary name in a test’s file names (see the user manual for details).

The DEBUG environment variable, which controls wether the test runner starts the interactive debugger, has been renamed to DEBUGGER.

The SIMULATOR_TARGET and SIMULATOR_INCLUDES parameters have been eliminated from test runners. The former is detected automatically. As for the latter, you can specify paths to directories in the SIMULATOR_SOURCES parameter instead.

The bench.rb and bench.v files of a generated test are (1) no longer generated by the test generator and (2) are now ignored. You must move the functionality provided by these files into design.rb and your Verilog module’s source file respectively.

The design.rb and proto.rb files are now loaded into a separate namespace (Ruby module). For example, if the Verilog module under test has the name “counter” and the design.rb file defines a class named “Foo”, then that class will be accessible as “Counter::Foo”.

The global Vpi::simulate method has been replaced by the cycle! method in the design.rb file.

The simulate! method in the proto.rb file has been renamed to feign! for accuracy.

The RubyVpi module has been renamed to RubyVPI.

RSpec >= 1.0.0 is now required by Ruby-VPI.

The project license has been further simplified.

Repairs

Restored support for Enumerable methods in Vpi::Handle.

The specification now begins to execute at simulation time 0. Previously it began at simulation time 1.

Improvements

The bench.rb and bench.v files of a generated test have been eliminated!
One important benefit is that the Ruby interface to the Verilog module under test is now a direct reference, whereas previously it was an indirect reference (it pointed to the Verilog module defined in bench.v, which in turn wrapped around the actual Verilog module under test).

As a result, you can now access the internals of the Verilog module under test by simply calling methods on the Ruby interface, as you would naturally expect to be the case.

The “a” accessor, which returns an array of child handles, has been added to the method naming format for accessing child handles.

All parameter objects in the Verilog module under test are automatically made available as constants. For example, if the Verilog module under test has the name counter and has a parameter object named WIDTH, then you can access the integer value of that parameter using Counter::WIDTH.

The automated test generator now tries to automatically detect the clock and reset signal from Verilog module declarations.

The automated test generator now supports Verilog 95 style module declarations.

Exceptions are now raised when you try to write to a read-only VPI property, such as VpiName.

Added high?, high!, low?, and low! methods to the Vpi::Handle class.

Revised the user manual by removing unnecessary sections and adding newer material from my master’s thesis.

Contributions

Added Jacinto Shy II’s register file example to Ruby-VPI. It can be found in samp/register_file/.

Version 16.0.1 released

Sun, 27 May 2007 00:00:00 PDT

Version 16.0.1 (2007-05-27)

This release restores support for installation on Mac OS X.

Thanks

Mark Thompson reported and solved the problem.

Repairs

Shared-object files have a file extension of .so in Linux and .bundle on Mac OS X. Previously, only the Linux file extension was supported.