VHDL Study Group Meeting 2/17/2011 8 am Attendees: Jerry Kaczynski - Aldec John Shields - Mentor Hans Tiggeler - Charles Gardiner - Consultant Chris Higgs David Koontz Charles Fulks Peter Flake Chuck Swart - Mentor Martin Thompson - TRW Automotive Jim Lewis - SynthWorks Discussion: This is an official IEEE study group meeting and is governed by the IEEE patent policy. Please read the following before the meeting: https://development.standards.ieee.org/myproject/Public/mytools/mob/slideset.pdf Review Meeting Minutes from Last Meeting Approve 1/26 Meeting Minutes. Motion: Charles G, Martin T. We finished our discussion of the P&P. They are posted here. http://www.eda.org/vasg/docs/p1076_wg_pp_0110.pdf We will vote on the P&P once NESCOM (IEEE-SA new standards committee) approves the working group. The following items were changed since the previous meeting. Section 6.5.3: i) Conduct electronic (email or web based) voting at the request of the Chair and report the results to the working group. If a Secretary is not elected by the working group, the chair or the chair's designee shall carry out these responsibilities. Section 6.5.4 If a Treasurer is not elected by the working group, the chair or the chair's designee shall carry out these responsibilities. Section 7.2 Entire section. Please see document. Section 7.3 Removed editing directions. Paragraph looks good as it stands as it leaves all decisions to be made at time of formation of subgroup. Section 9.4 Voting between Meetings refers us to IEEE Bylaw I-300.4(4). I found I-300.4(4) at the following link: http://www.ieee.org/about/corporate/governance/email_meetings.html I-300.4(4) states that we should be specifying the minimum allowed electronic balloting time. For voting on WG officers, this is specified in clause 6.2 of the P&P document. It would be natural to specify the minimum voting period for all other voting in clause 9.4, however, I feel intimidated by the P&P editing guidelines that say, "This clause shall be included and shall not be modified except to be compliant with the Sponsor’s procedures." I decided that IEEE is the ultimate sponsor, and as a result, that it is ok to add something to be compliant with I-300.4(4). So I added: "The minimum period for an electronic ballot, other than for officer elections, shall be at least 7 days." Note, I was originally thinking 10 days (so we could easily vote between meetings), but since I-300.4(4) had 7 as an example, I copied that. Initiate discussion of language change requirements Language Interfaces: Peter Flake: VHPI: calls from C into VHDL objects DPI: How does VHDL call C subprograms. John Shields: VHPI: similar to Verilog VPI Small API Large representation of information model implied by design. Build and extend simulation environment Write foreign subprograms and architectures control model - must work hard and overhead is fairly awkward for people wanting DPI: Quick interface into and out of C code with minimal overhead to user interface. VHPI and a DPI are complementary If need more than DPI simple interface will need VHPI Hans DPI: powerful - with simplistic interface and executes within a delta cycle however has no call backs VHDL to C and C to VHDL - can also have wait statements within VHDL side Foreign procedures - DPI style interface Procedure with an empty body that is declared as foreign Chris VHPI allows foreign architecture and register with simulator John Shields: Value of VHDL DPI for simplicity at user level Charles DPI: Connect VHDL to Verilog Hans: VHPI - data introspection? Chris Higgs VHPI - using call backs Charles VHPI - power user - more casual user if c lib for helping some tasks Chris agrees - big investment for infrastructure DPI - casual user DPI: does it play a role in mixed language interface (John S)? Charles G: Yes. Peter: Subprograms calling both ways, how do that in VHPI? In VHPI: register call backs In SV DPI: no register call backs, just do it directly DPI: supports structs & pointers VHPI is needed for complex data structures? Charles G: SV may support this in DPI Summary: Need simplified interface to other languges Investigate VHPI potential and potential need for simplified DPI access Meeting times: Is 8 am Pacific convenient? Please sound off on reflector. We have had quite good attendance and I would like to keep that, but if we can make it more convenient - particularly for those already attending then good. Next Meeting 2 weeks: Thursday March 3 at 8 am I am looking into web based conference solutions. So the conference number may change before the next meeting.