From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=BAYES_00,INVALID_DATE autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 1089ad,96ebc2bce9474f1a X-Google-Attributes: gid1089ad,public X-Google-Thread: 103376,96ebc2bce9474f1a X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 1994-09-28 12:01:18 PST Path: bga.com!news.sprintlink.net!howland.reston.ans.net!swrinde!news.dell.com!tadpole.com!uunet!winternet.com!mr.net!usenet From: "Paul Pukite" Newsgroups: comp.lang.vhdl,comp.lang.ada Subject: Re: Differences between Ada and VHDL Date: Wed, 28 Sep 94 13:24:34 CST Organization: Minnesota Regional Network Message-ID: <60650.pukite@daina.com> Reply-To: NNTP-Posting-Host: msp2-15.nas.mr.net X-Minuet-Version: Minuet1.0_Beta_16 X-POPMail-Charset: English To: bob@jrs.com Xref: bga.com comp.lang.vhdl:1744 comp.lang.ada:6268 Date: 1994-09-28T13:24:34-06:00 List-Id: Bob Sheraga wrote: >Can anyone refer me to a comprehensive discussion of the differences >between Ada and VHDL (primarily syntactical differences)? > >Thanks in advance. > >Bob Sheraga >bob@jrs.com I haven't seen one myself (I suppose you could get the two LRMs and compare page by page. That would be comprehensive!). Besides the syntactic "surface" similarities, Ada and VHDL have a common foundation in that they both emphasize strong typing, hierarchical organization, separation of interface from implementation, levels of abstraction, and maintainability through readability. The strong typing eliminates at least one class of errors from occurring, the hierarchical organization and interface conventions allow large teams of developers to work on a project, and the levels of abstraction permit either bottom-up or top-down system design techniques (Ada 9X also allows full object-orientation). With that said, a few syntactical differences do stand out: VHDL Ada ~~~~ ~~~ to, downto .. -- range (Ada requires a reverse keyword) inout in out -- one less keyword required in Ada library, use with, use -- use clauses have different semantics variable X X -- need a variable keyword to denote object constant X: X:constant -- constant declaration generic generic -- generic in Ada includes types, fxns, etc TextIO Text_IO -- File objects have different syntax Many parts of VHDL have no correspondence to Ada, such as: signals, entities, components, assert, attribute, physical types, etc. On the other hand, Ada has the following constructs you don't find in VHDL: private and tagged types, tasks, exceptions, delay, etc. I wouldn't try to compare VHDL concurrency and Ada concurrency as they don't have any real common ground (hardware modeling vs. operating system threads). However, if you want to compare only the sequential statements, flipping back and forth between the LRMs is justifiable if you need elaboration on a concept. -- Paul Pukite (pukite@daina.com) DAINA Engineering 612/781-7600 4111 Central AVE NE, Suite 212 Minneapolis, MN 55421-2953