[FAQ]

 

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Frequently Asked Questions

How long does it take to become proficient?

Hours, not days. The installation includes a full self-paced tutorial which takes a couple of hours to complete - after which you can start reaping the benefits.

How quick is the code generation process?

Code generation is blindingly fast, a 3m gate design will code generate in under 3 seconds from clicking the button. We even show the CG time in the CG dialog.

How easy is it to specify USE and LIBRARY clauses for VHDL?

During code generation Expressive builds a list of used types for each level. This information is translated into LIBRARY and USE clauses automatically. You can add your own additional clauses (if required) by editing the HDL source directly or if the clauses are global then they can be placed in the header.

Can I add synthesis directives at any level?

In short yes - you can directly edit the HDL source files at any level, thus can add any additional code.

Can I link in my own text editor?

Yes - the Binding wizard takes you through the process step by step. Once the system knows about your editor, access to functional code is by a simple double click over a design unit (same as pushing down a level).

Will this mess up my design flow?

No - you are simply deploying Expressive on the part of your flow where you previously used a text editor. At the end of the day Expressive produces well formatted HDL source files, which are independent of Expressive. There are no proprietary databases at all.

Does Expressive co-exist with source code control systems?

Yes - all files generated by Expressive are plain ASCII files. All of which can be checked in using delta modes. The code generator only updates a file on disk if there are changes.

Are there any proprietary data bases or files?

None - apart from the executable, licensing s/w, images, all files read by and generated by Expressive are plain ASCII files. We, as a company, do not believe in locking customers to proprietary file formats. We are quite happy to discuss the structure of our ASCII file format with bone-fide customers with real needs in mind.

Could I use Expressive purely as a documentation tool?

Yes, at some stage in your project a team member will need to produce hierarchy diagrams. Typically a tool, any tool, which has drawing capability is chosen. These tools don't understand hierarchy and rarely provide the ability to 'connect' objects together in any useful way.

There is no reason why Expressive could not be used purely as a documentation tool - it would offer significant productivity increases over other tools.

Can I extract sub-ranged signals from a larger bus? i.e. dBus[4-7] from dBus[0-63]

Very easily. Just type in the range you want, Expressive will automatically range check for you. The original sub-range is preserved across hierarchical boundaries preserving the original intent. Expressive has a very flexible signal handling capability.

Do you use awkward bus rippers to access bits?

No - you can access bits of a bus or a contiguous range by simply typing in the index or range required at any boundary point. Both range extract or merge is equally supported. More complex 'bit slicing' can be accomplished by the slice and splice editor access from a junction.

If you have any questions not covered here please contact us, we do our best to return answers by the next working day. See contact information for email address.