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Messages from 575

Article: 575
Subject: [shin]OrCad .sch to Xilinx .xdf conversion seeking
From: gshin@netcom.com (George Shin)
Date: Mon, 9 Jan 1995 05:36:20 GMT
Links: << >>  << T >>  << A >>
Does anyone come across utility that will allow taking in Orcad .sch or
OrCad netlist file format and convert to Xilinx's .xdf format (suitable
for using its FPGA)?  Thanks much in advance.  If i'm going about in wrong
directoy, please let me know.  Thanks again.

-gshin



Article: 576
Subject: Actel + Mentor Graphics
From: olsson@plasma.kth.se (Goran Olsson, Plasma Physics, KTH)
Date: 9 Jan 1995 09:56:20 GMT
Links: << >>  << T >>  << A >>

We are looking at purchasing a development system for Actel to run on a
HP workstation with a Mentor Graphics environment. Is there anyone out
there using this combination?

=========================================================================
                              Goran Olsson
 Alfven Laboratory, Plasma Physics, Space Group, Electronic Engineering,
         KTH (Royal Institute of Technology), Stockholm, Sweden
        F1 - The Electric Field Experiment on the FREJA satellite
                      Two years in orbit 6 Oct 1994
                           olsson@plasma.kth.se
=========================================================================


Article: 577
Subject: Re: Motorola FPGA
From: hadlich@news.cs.tu-magdeburg.de (Thomas Hadlich)
Date: 9 Jan 1995 13:54:44 GMT
Links: << >>  << T >>  << A >>
Chuang Hsien-Ho (eea80593@twis.EE.NCTU.edu.tw) wrote:
> I want to find some information about look-up table-based FPGA
> made be Motorola. Could anyone help me? Thanks.

> --
> ===============================
> Hsien-Ho Chuang     
> eea80593@yankees.ee.nctu.edu.tw
> ===============================


I would also like to get some information on these devices, so please answer
as follow up.

Thomas

--
--------------------------------------------------------------------------
|    Thomas Hadlich      Thomas.Hadlich@E-Technik.Uni-Magdeburg.DE       |
|                        hadlich@infaut.et.uni-magdeburg.de              |
--------------------------------------------------------------------------


Article: 578
Subject: Re: Motorola FPGA
From: wolf@aur.alcatel.com (William J. Wolf)
Date: 9 Jan 1995 16:36:41 GMT
Links: << >>  << T >>  << A >>
Personally, I think request for basic info is a waste of the net.  Call Motorola 
or a distributor and ask them for their data book, DL201/D "FPGA Data, Field 
Programmable Gate Arrays.  You might also contact NeoCAD - Motorola uses their 
FPGA tools.

Is there anyone out there who is willing to put together a contact list for 
FPGA & tool vendors to take care of simple questions like this?  Perhaps a 
consultant who wouldn't mind frequently posting their name on the net.

Now, if anyone has early user experiences with Motorola FPGAs, pros & cons 
versus other FPGAs etc, I would like to here that.  That is something I can't 
get by taking the trouble to pick up the phone and call a vendor.

---
~ Bill Wolf, Raleigh NC           ~          I can see         ~
~ wolf@aur.alcatel.com            ~           the fog          ~
~ My opinions, NOT my employer's  ~  at the end of the tunnel  ~




Article: 579
Subject: Lee Fadden, what is your address?
From: randraka@ids.net
Date: Tue, 10 Jan 95 14:26:28 GMT
Links: << >>  << T >>  << A >>
If anyone knows Lee Fadden's (Harris) complete E-mail address please send it to
me.  The address I have, lfadden@harris.com comes back as undeliverable.

-Ray Andraka  randraka@ids.net
 


Article: 580
Subject: Re: Motorola FPGA
From: telkamp@eis.cs.tu-bs.de (Gerrit Telkamp)
Date: 10 Jan 1995 18:01:10 GMT
Links: << >>  << T >>  << A >>
In Article 648 Chuang Hsien-Ho (eea80593@yankees.ee.nctu.edu.tw) writes:

>I want to find some information about look-up table-based FPGA
>made be Motorola. Could anyone help me? Thanks.
>
>--
>===============================
>Hsien-Ho Chuang     
>eea80593@yankees.ee.nctu.edu.tw
>===============================

Motorola's FPGA architecture has been developed by a small british design company
(Pilkington). Engeneering samples will be available during this quarter.

You'll find some informations at
   http://www.demon.co.uk/pmel/index.html
Or send an email to 
   email info@pmel.com
Also you can download a demonstration version of the software package, which works
only for the smallest device of the family (PMEL 1036, I think)
        - ftp ftp.cica.indiana.edu
        - ftp micros.hensa.ac.uk
        cd pub/cica/win3/demo  
        pmelcore.zip

Hope this helps,

Gerrit.
-----------------------
telkamp@eis.cs.tu-bs.de






Article: 581
Subject: Re: Fpga programming
From: khurley@ea.com
Date: 10 Jan 1995 22:04:02 GMT
Links: << >>  << T >>  << A >>


In article <D1zu5s.4FA@eunet.ch> roman@pax.eunet.ch (rroman pollak) writes:

It is said that Intel gives theirs away for free, try ftp.intel.com,
it's a big site however, try under flex or something like that
I however prefer Lattice Semiconductor ISP LSI devices, their starter kit
is $99.00 and runs under window, it only supports the 1016 device, 32 I/O
roughly 2000 pld gates.  The upgrade is $650.00 for the higher density devices.
What I really like about these is they are in-circuit programmable.  For Proto-
typeing you can just build a board, and later figure the logic that goes into
them.....


>Is there a Software on an Anonymous ftp ,to can programm resp. desing a
>fpga with my circuits .
>I am a normal mortal person, for my is it vary expensive to buy
>the original Software mybe for one or two chips programm.
>And for the local distributer have the hole installation ,
>it is also very expensive .
>I would like to build my dream Graphic Processor it is
>possible with ttl but with 30-40 ic's.
>regards,
>roman


Article: 582
Subject: PCB design with Xilinx
From: weathert@ee.umr.edu (Terry Chevalier)
Date: 11 Jan 1995 17:34:37 GMT
Links: << >>  << T >>  << A >>
	I am currently designing a board that is using both 240 pin and 208
pin quadflat pack packages for the 4013 and 4010 xilinx chips respectively.
My problem is finding specifications for the design of the footprint of these
chips.  I am using Mentor graphics boardstation which contains some basic
pads but nothing very complex.  I have checked several books both at our
library at UMR and others through interlibrary loan.  If anyone could point
me to reference material to design the pads for these chips I would appreciate
the time spent.
William Eatherton



Article: 583
Subject: Backannotating Xilinx pinouts to ViewLogic symbols... BUT Not by hand!
From: mrivero@emerald.tufts.edu (Marco Rivero)
Date: 11 Jan 1995 13:37:36 -0500
Links: << >>  << T >>  << A >>

Hi,

The problem is simple:  I've got a schematic with a Xilinx part symbol.  
After routing the Xilinx part, and after everytime I change my pinout 
(since the pcb hasn't been made yet) I need to update all the pin number 
attributes on the symbol.  The pin information is available in the 
Xilinx netlist (.xnf), but it doesn't get backannotated into the ViewLogic 
wir file by XNF2WIR.  Viewgen could be used to create a new symbol from 
the wir file (but without the pin info, this is almost useless).  Xilinx 
said: "Ask Viewlogic"; Viewlogic said "ask Xilinx!"

Has anyone foud a way to transfer all the pin information 
(pintype=I/O/B; #=pinnumber) to the symbol on the top level schematic? or 
maybe written a piece of code to do it?  

I would appreciate any info.  Thanks!
Marco
-- 
-----
  Marco Rivero                        mrivero@tufts.edu


Article: 584
Subject: Re: Backannotating Xilinx pinouts to ViewLogic symbols
From: allen@hex.viewlogic.com (Dave Allen)
Date: 11 Jan 1995 12:07:28 -0800
Links: << >>  << T >>  << A >>
Marco Rivero (mrivero@emerald.tufts.edu) writes:

> The problem is simple:  I've got a schematic with a Xilinx part symbol.  
> After routing the Xilinx part, and after everytime I change my pinout 
> (since the pcb hasn't been made yet) I need to update all the pin number 
> attributes on the symbol.  The pin information is available in the 
> Xilinx netlist (.xnf), but it doesn't get backannotated into the ViewLogic 
> wir file by XNF2WIR.  Viewgen could be used to create a new symbol from 
> the wir file (but without the pin info, this is almost useless).  Xilinx 
> said: "Ask Viewlogic"; Viewlogic said "ask Xilinx!"
> 
> Has anyone foud a way to transfer all the pin information 
> (pintype=I/O/B; #=pinnumber) to the symbol on the top level schematic? or 
> maybe written a piece of code to do it?  

Well, here is one way this could be done.  I don't know of any code which
does it.   But first, a disclaimer:  this is only a proposal, not a
commitment to do it.

In the Xilinx <-> Viewlogic path, Viewlogic's tools do not read xnf.  The
tools which read and write xnf are written and distributed by Xilinx.  This
path can be made to work if (1) Xilinx modifies xnf2wir to pass the
pin number and pin type information into the wir file and (2) Viewlogic
makes sure that Viewgen will use the information to put it on the symbol.

- Dave Allen: allen@viewlogic.com


Article: 585
Subject: Re: Backannotating Xilinx pinouts to ViewLogic symbols
From: mmoeller@delphi.com
Date: Wed, 11 Jan 95 20:09:48 -0500
Links: << >>  << T >>  << A >>
Dave Allen <allen@hex.viewlogic.com> writes:
 
>> The problem is simple:  I've got a schematic with a Xilinx part symbol.  
>> After routing the Xilinx part, and after everytime I change my pinout 
>> (since the pcb hasn't been made yet) I need to update all the pin number 
>> attributes on the symbol.  The pin information is available in the 
 
I have some awk code that does what want for Orcad. Orcad has an Ascii
format for libray source files. One prgram makes the symbol the first time
another updates it, flags moved and new pins etc.
If Viewlogic has a simialr input path this may be of use.
If interested send me a note and I will see mail it to you, if I get
othere requests I will post it.
It is tested only on 3000 series parts but shoudl work for others,
some care is needed in use as is the case with most software written
for "self use".
 
>Well, here is one way this could be done.  I don't know of any code which
>does it.   But first, a disclaimer:  this is only a proposal, not a
>commitment to do it.
>
>In the Xilinx <-> Viewlogic path, Viewlogic's tools do not read xnf.  The
>tools which read and write xnf are written and distributed by Xilinx.  This
>path can be made to work if (1) Xilinx modifies xnf2wir to pass the
 
It may be posible to get .xnf with Pin# in it already, would show up as
atributes. I have not tried this I simply extract the pin# from the
lca file (which is verbose but esaily parsed ascii).
I do not back annotate pin types, they are noted when the file is
first made.  My code can also generate an "Orcad stuff" file to
back annotate the pin # onto the schamtic of the Xilinx part.
BTW, The program I mentioned before manages the Schematic symbol of the
FPGA part that is being designed. The other part helps update the schematic
OF the FPGA being designed. ( Almost forgot that I ahve been working
primarly in VHDL for FPGA design lately).
 
Martin Moeller
mmoeller@delphi.com
 
Moeller, Inc.
We do video in Xilinx.


Article: 586
Subject: ASIC '95 Call For Papers
From: rauletta@site.gmu.edu (Not who you think)
Date: 12 Jan 1995 01:18:53 GMT
Links: << >>  << T >>  << A >>


-------------------------------------------------------------------
       #     #####    ###    #####            ###    #####  #######
      # #   #     #    #    #     #           ###   #     # #
     #   #  #          #    #                  #    #     # #
    #     #  #####     #    #                 #      ###### ######
    #######       #    #    #                             #       #
    #     # #     #    #    #     #                 #     # #     #
    #     #  #####    ###    #####                   #####   #####

                               Eighth Annual
                 APPLICATION SPECIFIC INTEGRATED CIRCUIT
                       Conference and Exhibit 1995

               "Implementing the Information Superhighway 
                       with Emerging Technologies"

                         Stouffer Renaissance Hotel
                              Austin, Texas
                             September 18-22


                 CALL FOR PAPERS, TUTORIALS, & WORKSHOPS 

  The IEEE International ASIC Conference and Exhibit  provides a forum
  for examining current issues related to ASIC applications and system
  implementation, design, test, and design automation.  The conference
  offers a  balance of emphasis on  industry standard  techniques  and 
  evolving research topics. Information is exchanged through workshops,
  tutorials,  and paper presentations.  These promote an understanding
  of the current technical challenges and issues of system integration
  using  programmable logic devices, gate arrays, cell based  ICs, and
  full custom ICs in both digital and analog domains.  
  ____________________________________________________________________

  Technical Papers, Tutorials, and Workshop Proposals are solicited in
  the following areas: 

ASIC Applications:    Wireless Communications, PC/WS and Peripherals,
                      Multimedia, Networking, Image Processing, Data
                      Communications, Storage Technologies, Graphics, 
                      Digital Signal Processing 

Technologies:         Digital, Analog, Mixed Signal, CMOS, BiCMOS, ECL,
                      GaAs 

CAD Tools:            Design Capture, Layout, Test, Synthesis,
                      Modeling, Simulation  

Architectures:        PLDs, Gate Arrays, Cell Based ICs, Full Custom ICs 

Evolving Research:    Research in Methodologies, Tools, Technologies &
                      Architectures  

Design Methodologies: System Design, Top-down, Graphical, HDLs  

Manufacturing:        Process, Testability, Packaging 

Workshops: Four or eight hour technical workshops covering ASIC design
knowledge and skills.  Proposals to form these workshops for either
introductory or advanced levels are invited. ASIC industry as well as
universities are encouraged to submit proposals. Contact the Workshop
Chair.  

______________________________________________________________________

                       INSTRUCTIONS TO AUTHORS 

Authors of papers, tutorials, and workshops are  asked to submit 15
copies of a review package that consists of a  500 word summary and
a title page. The title page should include the technical area from
above, the title,  a 50 word abstract, the authors names as well as 
an indication of the primary contact author with a COMPLETE mailing
address,  telephone number and TELEX/FAX/Email.  The summary should
clearly state:   1) title of the paper;  2) the purpose of the work; 
3) the major contributions to the art; and  4) the specific results 
and their significance.  

                           IMPORTANT DATES

            Summaries and Proposals due:      March 3, 1995 
            Notification of Acceptance:      April 14, 1995 
            Final Camera Ready Manuscript due: June 2, 1995 

                        SEND REVIEW PACKAGE TO 

                        Lynne M. Engelbrecht 
                        ASIC Conference Coordinator 
                        1806 Lyell Avenue 
                        Rochester, NY 14606 
                        Phone: (716) 254-2350 
                        Fax: (716) 254-2237 

CONFERENCE INFORMATION 
http://asic.union.edu 
Proceedings, and the Advance Program 
Airline Discounts, Exhibits, Technical Sessions, 
Schedule, Registration, Hotel Sites, 


CONFERENCE CHAIR	TECHNICAL CHAIR		WORKSHOP CHAIR
William A. Cook		Richard A. Hull 	P. R. Mukund
Eastman Kodak Co.	Xerox Corp.		RIT
Rochester, NY 14650	Webster, NY 14580	Rochester, NY 14623
Phone: (716) 477-5119 	Phone: (716) 422-0281	Phone: (716) 475-2174
Fax: (716) 477-4947 	Fax: (716) 422-9237 	Fax: (716) 475-5845
bcook@kodak.com 	rah.wbst102a@xerox.com 	mukund@cs.rit.edu


EXHIBIT CO-CHAIRS

Kerry Van Iseghem 	Kenneth W. Hsu
LSI Logic Corporation 	RIT
Victor, NY 14564	Rochester, NY 14623
Phone: (716) 223-8820	Phone: (716) 475-2655
Fax: (716) 223-8822	Fax: (716) 475-5041
kerryv@lsil.com		kwheec@ritvax.isc.rit.edu

               Sponsored by the IEEE Rochester Section 
        in cooperation with the Solid State Circuits Council  
	            and the IEEE Austin Section
-------------------------------------------------------------------


Article: 587
Subject: Re: Motorola FPGA
From: dgamble@wimsey.com (Don Gamble)
Date: Wed, 11 Jan 1995 22:07:12
Links: << >>  << T >>  << A >>
>Motorola's FPGA architecture has been developed by a small british design 
>company(Pilkington). Engeneering samples will be available during this 
>quarter.

The Pilkington AutoLayout tool will handle all of the Motorola devices.
It will work as a back-end to Capilano Computings DesignWorks schematic
capture or ViewLogics schematic.

Demos of the Pilkington back-end tools and of the DesignWorks front-end
can be downloaded from ftp.wimsey.com in /pub/capilano/demo.

Don Gamble


Article: 588
Subject: Re: Backannotating Xilinx pinouts to ViewLogic symbols... BUT Not by hand!
From: postmaster@lsantist.dfrf.nasa.gov
Date: Thu, 12 Jan 1995 19:40:13 GMT
Links: << >>  << T >>  << A >>

In article <3f18hg$vd7@emerald.tufts.edu>, <mrivero@emerald.tufts.edu> writes:
> 
> Hi,
> 
> The problem is simple:  I've got a schematic with a Xilinx part symbol.  
> After routing the Xilinx part, and after everytime I change my pinout 
> (since the pcb hasn't been made yet) I need to update all the pin number 
> attributes on the symbol.  The pin information is available in the 
> Xilinx netlist (.xnf), but it doesn't get backannotated into the ViewLogic 
> wir file by XNF2WIR.  Viewgen could be used to create a new symbol from 
> the wir file (but without the pin info, this is almost useless).  Xilinx 
> said: "Ask Viewlogic"; Viewlogic said "ask Xilinx!"
> 
> Has anyone foud a way to transfer all the pin information 
> (pintype=I/O/B; #=pinnumber) to the symbol on the top level schematic? or 
> maybe written a piece of code to do it?  
> 
> I would appreciate any info.  Thanks!
> Marco
> -- 
> -----
>   Marco Rivero                        mrivero@tufts.edu

Hi Marco!  I have RTFM over and over again to see if some Viewlogic facility
will allow this.  It may be possible with PCBBCK, which is intended to 
backannotate from an external PCB layout system and it operates in a very
general way.  However, trying to figure it all out takes a lot of time 
which I have very little; So, I end up doing it "by hand".  If you ever find 
a solution to this, I would sure like to hear about it.  

BTW, I do automate this slightly by first entering the pin number as the 
attribute value and then using the Windows recorder applet to rapidly add 
the common prefix (i.e. the "#=").


Article: 589
Subject: Xilinx marketing knuckleheads
From: dh@fncrd7.fnal.gov (don husby)
Date: 12 Jan 1995 21:35:02 GMT
Links: << >>  << T >>  << A >>

Disclaimer: I am not an employee of Xilinx, AT&T, or NeoCad.

The local Xilinx guy left a Xilinx brochure on my desk this morning 
titled: "Xilinx 4000 vs. AT&T ORCA FPGAs: A feature comparison."

It's filled with half-truths and downright lies regarding ORCA.  You 
should watch out for this.  Certainly, someone at Xilinx should be 
slapped upside the head for producing something this deceptive: it 
makes me wonder if Xilinx can now be written off completely as being run 
by dimwitted marketing types. (Leaving iterative design out of their 
original X4000 design flow was probably the first indication of this.)

An example of misrepresentation of truth is Table 1. Logic block 
utilization for various functions:

X4000	ORCA	Circuit
-------------------------------------------------------------
1 CLB	2 PFU	9-bit parity
		The truth is: ORCA can implement up to 11 bits of
		parity with a single PFU.

1 CLB	4 PFU	8-bit registered-input parity generator.
+8 IOB	+8 IO	The truth is: while ORCA does not have registered I/O, the PFU
		registers can be connected directly to I/O pads.  It only
		takes 2 PFU to implement this circuit.

1 CLB	2 PFU	6-input function and sync of a separate signal. 
		The truth is: X4000 can NOT implement completely-covered
		6-input functions in a single CLB. The ORCA CAN implement full
		6-bit functions AND has 4 registers that can be used
		independently for synchronization.
-------------------------------------------------------------


The truthful comparison of logic capacity per CLB/PFU is:
================================================================================
				X4000			ORCA 2C
Fully covered functions:	5-bits			6-bits
				1 independent FF	4 independent usable FF
Partially covered functions:	9-bits + 1 ind. FF	11-bits + 4 ind. FF
RAM capacity:			16x2			16x4
RAM capacity:			32x1			32x2

Plus ORCA has payed attention to making single PFU implementation of other
functions:

X4000	ORCA 2C
-----------------
2 CLB	1 PFU	Quad 2-1 multiplexer.
2 CLB	1 PFU	Dual 4-1 mux with registered output. (ORCA uses a trick).
		Each flip-flop has a multiplexed input that can select either 
		the function generator or a direct input.  In addition to 
		extending the logic capability for registered functions, this 
		is intended to be used to create loadable counters:
4 CLB?	1 PFU	4-bit loadable up/down counter with synchronous reset.


Of course, the useful comparison between ORCA and X4000 is the performance and
cost.  Since each ORCA PFU is between 1.5 and 2.5 times the functionality of a 
Xilinx CLB, you might expect similar-sized ORCA parts to cost about twice as 
much as their X4000 counterparts.  Anyone have the latest prices?

Final note:
  Xilinx also compares its software to AT&T's develompment system.  When I 
called the local AT&T sales office, they recommended that I get NeoCad.  They 
admit that NeoCad has more experience at this kind of software.  I've just 
purchased a NeoCad system and find it superior in many ways (but not all) to 
Xilinx.

  I'm sorry if this sounds like I'm ragging on Xilinx.  I still feel that 
Xilinx offers excellent products and service.  It's just dissappointing to see 
such blatant lies and half-truths coming from their marketing folks.  
If I didn't know better, I'd swear they hired Rush Limbaugh to write it.


Article: 590
Subject: Re: PCB design with Xilinx
From: postmaster@lsantist.dfrf.nasa.gov
Date: Thu, 12 Jan 1995 23:02:36 GMT
Links: << >>  << T >>  << A >>

In article <3f14rd$ati@hptemp1.cc.umr.edu>, <weathert@ee.umr.edu> writes:
> 
> 	I am currently designing a board that is using both 240 pin and 208
> pin quadflat pack packages for the 4013 and 4010 xilinx chips respectively.
> My problem is finding specifications for the design of the footprint of these
> chips.  I am using Mentor graphics boardstation which contains some basic
> pads but nothing very complex.  I have checked several books both at our
> library at UMR and others through interlibrary loan.  If anyone could point
> me to reference material to design the pads for these chips I would appreciate
> the time spent.
> William Eatherton
> 

I have never been able to find a "specification" for Plastic Quad Flat Packs.  
These are Japanese standards which differs from similar "JEDEC" standards used 
by most American engineers.  There are lots of pitfalls for the unaware.  One of
the problems is that these standards are metric but most boards designed in the 
U.S. are based on an english grid.  If you simply convert the metric dimensions 
to english so as to match the grid, you end up with an error that accumulates the 
farther you get from the datum.  This is specially bad in large package such as 
208 or 240 pins where there is little room for error; It simply won't work!  The 
only solution I am aware of is to use a PCB layout system that can accomodate both 
an english and a metric grid and a PCB designer that can use it effectively.  
Some years back, I heard that JEDEC was working on standards to sort out the 
differences, but I don't know what became of it.

I have always been able to avoid the problem by using ceramic PGA packages, but 
board space constrains will force me to adopt these metric packages in my current 
design.  My approach will be to use IPC-D-275 for general guidelines.  As a final 
authority, I will rely on my PCB fabricator and board assembly house to check the 
work of my PCB designer, since these folks deal with these problems every day.

Document Engineering has the IPC spec (and most other technical specs).  Their 
voice number is (818)782-1010.  You might want to check out the Xilinx Customer 
Support BBS at (408)559-9327.

BTW, I would be very interested in reading other opinions on this subject.

--
Lou Santisteban   
Computer Sciences Corporation     Email - lsantist@lsantist.dfrf.nasa.gov
P.O. Box 387                      Phone - (805)258-3786
Edwards, CA 93523-0387            Fax   - (805)258-3567
"The difference between good and excellent is details", Unknown

I DO NOT SPEAK FOR CSC, NASA, OR ANYONE ELSE BUT MYSELF!



Article: 591
Subject: ViewLogic simulation without master reset
From: med440@aol.com (Med440)
Date: 12 Jan 1995 23:10:50 -0500
Links: << >>  << T >>  << A >>
I have inherited an Actel FPGA design which was done using ViewLogic and
I'm preparing to convert it to a semi-custom "sea-of-gates" chip.  
Unfortunately, no simulation of the design was ever done, and simulation
files are required by the people doing our conversion.   The simulation
has fallen into my hands, and my very limited FPGA experience has already
gotten me into trouble -- here goes:  Many of the flip-flops in the
current design do not have any reset/preset.  Because of this, predicting
the state at power-on is impossible, as is generating the
"print-on-change" type data required.   I don't think the lack of a master
reset(or any reset) is a real problem from a design standpoint, as most of
the FFs without resets are in clock-divider chains where state is not
really an issue -- it's only from a simulation standpoint that this is
troublesome.

Any ideas on how this is commonly done, or why it should never be done,
will be appreciated.

Med Dyer
JABRA Corp.


Article: 592
Subject: FPGA '95 Advance Program/ time to send in your registration
From: pak@cse.ucsc.edu (Pak K. Chan)
Date: 13 Jan 1995 15:59:24 GMT
Links: << >>  << T >>  << A >>
			FPGA `95 Advance Program
			------------------------

1995 ACM Third International Symposium on Field-Programmable Gate Arrays

			February 12-14, 1995
		    Marriott Hotel, Monterey, CA, USA

Note: The Symposium location is now Monterey.

Sponsored by ACM SIGDA, and Actel Corp., Altera Corp. and Xilinx, Inc.


Field-Programmable Gate Arrays (FPGAs) have revolutionized ASIC design by 
providing fast turnaround and negligible overhead cost. The challenge in 
FPGA research is to improve the speed and density of the devices, and find 
new CAD synthesis algorithms that make effective use of the new architectures. 
The objective of this symposium is to bring together people who are working 
in the many areas of research that are necessary to make a complete FPGA and 
high-capacity PLDs. 

The technical program consists of papers concerning FPGAs and High-Capacity 
PLD device architecture, Computer-Aided Design of these devices, architecture 
of multi-FPGA systems and CAD tools associated with these systems. In addition, 
there are several papers concerning applications of programmable logic.

The Symposium will be of interest to those developing FPGA architectures, both 
at the chip and board level, and those developing CAD algorithms for FPGAs. 
The Symposium is not of direct interest to immediate users of FPGAs.

General Chair: Pak K. Chan, UC Santa Cruz
Program Chair: Jonathan Rose, University of Toronto

Program Committee

Duncan Buell, SRC
Pak K. Chan, UCSC
Jason Cong, UCLA
Carl Ebeling, U. Washington
Ewald Detjens, Exemplar
Frederic Furtek, Atmel
Dwight Hill, Synopsys
Sinan Kaptanoglu, Actel
John McCollum, Actel
Jonathan Rose, U. Toronto
Richard Rudell, Synopsys
Rob Rutenbar, CMU
Takayasu Sakurai, Toshiba
Martine Schlag, UCSC
Tim Southgate, Altera
Steve Trimberger, Xilinx

Program
-------

Sunday February 12, 1995

6:00pm	Registration

7:00pm	Welcoming Reception, Marriott Hotel, Monterey

Monday February 13, 1995

8:20am	Opening Remarks

Session 1: General Purpose Architecture 

Chair: Tim Southgate, Altera

8:30am	On Designing ULM-Based FPGA Logic 
        Modules, S. Thakur, D.F. Wong, U. of Texas

8:50am	Using Architectural "Families" to Increase FPGA 
        Speed and Density, V. Betz, J. Rose, U.  Toronto

9:10am	Design of FPGAs with Array I/O for Field 
        Programmable MCM, J. Darnauer, J. Ramirez, 
        W. W-M. Dai, U. of Cal. Santa Cruz

Posters: General Purpose Architecture

9:30-10:30am Coffee & Posters	

Session 2: Field-Programmable Systems

Chair:	Carl Ebeling, University of Washington

10:30am	TIERS: Topology Independent Pipelined Routing 
        and Scheduling for Virtual Wire Compilation, 
        C. Selvide, A. Agarwal, M. Dahl, J. Babb, Virtual 
        Machine Works, MA.

10:50am	Logic Partition Orderings for Multi-FPGA 
        Systems, S. Hauck, G. Borriello, U. Wash.

11:10am	An FPGA-Based Reconfigurable Co-processor 
        Board Utilizing a Mathematics of Arrays, H. 
        Pottinger, W. Eatherton, J. Kelly, T. Schiefelbein, 
        U. of Missouri - Rolla

Posters: Field-Programmable Systems 11:30-12

LUNCH 12:00 - 1:30

Session 3: Applications I

Chair: Pak K. Chan, UCSC

1:30pm	High-Energy Physics on DECPeRLE-1 
        Programmable Active Memory, L. Moll, 
        J. Vuillemin, P. Boucard, Digital Equip. Corp, 
        Paris Res. Lab, France

1:50pm	HGA: A Hardware-Based Genetic Algorithm, 
        S. D. Scott, A. Samal, S. Seth, Wash. Univ, 
        U. of Nebraska-Lincoln

2:10pm	The U.S.C. Multiprocessor Testbed: A Rapid 
        Prototyping Engine, K. Oner, L. Barroso, 
        S. Iman, J. Jeong, K. Ramamurthy, M. Dubois, 
        U.  Southern California

Posters: Applications

2:30-3:30pm Coffee & Posters

Session 4: Logic Synthesis

Chair:	Richard Rudell, Synopsys

3:30pm	Simultaneous Depth and Area Minimization in 
        LUT-Based FPGA Mapping, J. Cong, 
        Y-Y. Hwang, U. of California, L.A.

3:50pm	Synthesis of Signal Processing Structured 
        Datapaths for FPGAs Supporting RAMs and 
        Busses, B. Haroun, B. Sajjadi, Concordia 
        University.

4:10pm	On Nominal Delay Minimization in LUT-Based 
        FPGA Technology Mapping, J. Cong, Y. Ding, 
        UCLA.

Posters: Logic Synthesis and Co-Design

4:30-6:00pm Free time/Posters

Dinner 6:00-7:30pm



7:30-9:00pm  PANEL

The Architecture/Software Boundary:

Motherhood & Lies.

The most crucial element in the creation of an FPGA is the 
interaction between the device architecture and the software 
tools that map circuits into the device. The architect should 
determine the ability of the placement and routing software, 
for example to:

i.  Deal with routing architecture's overall structure 
    (such as symmetric vs. asymmetric; hierarchical vs. 
    flat, segmented routing etc.)

ii. Handle special purpose connections, such as carry 
    chains, local interconnect or hard-wired connections.

iii.Route typical circuits with the fixed total amount of 
    interconnect. For example, should different-sized 
    parts be given different quantities of routing?

Similarly the architecture should be able to deal with the 
capability of the logic synthesis tools to handle:

i.  The structure and function of the logic block.

ii. Special logic block features such as adder logic, clock 
    qualifiers and logic sharing capability.

iii.The effect of the synthesis on the routability of the 
    synthesized netlist.

Although FPGA vendors and academic architects will 
immediately agree with that this interaction is essential, and 
is indeed a motherhood issue, it is actually rare that these 
interactions are enforced. Similarly, synthesis vendors (and 
University CAD researchers) may claim to produce FPGA 
architecture-specific algorithms but the reality is otherwise. 
What makes it so difficult?

Is interaction really important, or will the effects of poor 
interaction be swallowed by the next generation IC process 
advance? Perhaps some very clever interactions can produce 
major density and speed gains FPGA devices.

If interaction is difficult to enforce for general-purpose 
FPGA architectures, will it be possible to create a next 
generation of special-purpose architectures?

This panel will explore these issues by bringing together 
several people from the FPGA vendor community, the 
FPGA user community, synthesis vendors and researchers.

Tuesday February 14, 1995

Session 5: Architecture of Special-Purpose Structures

Chair:	Steve Trimberger, Xilinx

8:30am	Revisiting the Cascade Circuit in Logic Cells of 
        Lookup Table Based FPGAs, N-S. Woo, AT&T 
        Bell Labs, N.J.

8:50am	Architecture of Centralized Field-Configurable 
        Memory, S.J.E. Wilton, J. Rose, Z.G. Vranesic, 
        U.  Toronto

9:10am	A Field-Programmable Mixed-Analog-Digital 
        Array, P. Chow, P. Chow, P.G. Gulak, 
        U.  Toronto


Posters: Special-Purpose Architecture

9:30-10:30am Coffee & Posters	

Session 6: Placement, Routing & Testing

Chair:	Jason Cong, UCLA

10:30am	PathFinder: A Negotiation-Based Performance-
        Driven Router for FPGAs, L.E. McMurchie, 
        C. Ebeling, U. Washington

10:50am	Applications of Slack Neighborhood Graphs to 
        Timing Driven Optimization Problems In 
        FPGAs, A. Mathur, K.C. Chen, C.L. Liu, 
        U. Illinois, Fujitsu America, San Jose

11:10am	Testing of Uncustomized Segmented Channel 
        Field Programmable Gate Arrays, T. Liu, 
        W.K. Huang, F. Lombardi, Texas A&M University

Posters: Routing and Fault-Tolerance 11:30-12 

LUNCH 12:00 - 1:30

Session 7: Multi-FPGA Partitioning

Chair:	Martine Schlag, UCSC

1:30pm	Spectral-Based Multi-Way FPGA Partitioning, 
        P.K. Chan, M.D.F. Schlag, J.Y. Zien, U. of 
        California, Santa Cruz

1:50pm	Multi-Way System Partitioning into Single or 
        Multiple Type FPGAs, D. J-H. Huang, A.B. 
        Kahng, UCLA

2:10pm	Multiple FPGA Partitioning with Performance 
        Optimization, K. Roy-Neogi, C. Sechen, U. 
        Washington

2:30-3:30pm Coffee & Posters

Session 8: Applications and Bit-Serial Synthesis

Chair:	Sinan Kaptanoglu, Actel

3:30pm	Techniques for FPGA Implementation of Video 
        Compression Systems, B. Schoner, J. Villasenor, 
        S. Molloy, R. Jain, UCLA.

3:50pm	An SBus Monitor Board, H.A. Xie, K.E. 
        Forward, K.M. Adams, D. Leask, U. Melbourne, 
        Australia

4:10pm	High-Level Bit-Serial Datapath Synthesis for 
        Multi-FPGA Systems, T. Isshiki, W. W-M. Dai, 
        U. California, Santa Cruz

Posters: Applications 4:30-5:00


		    FPGA `95 REGISTRATION
		    ---------------------

The Symposium registration fee includes a copy of the symposium proceedings, 
a reception on Sunday evening, February 12, coffee breaks, continental breakfast 
on the first day, lunch on both days, and dinner Monday evening, February 13.

First Name:___________________________________________
Last Name:____________________________________________
Company/Institution___________________________________
Address:______________________________________________

City:___________________State:_____________
Postal Code:_______________Country:____________

Email:________________________________________
Phone:_______________________Fax:_______________________

Circle Fee	Before January 25, 1995 	After January 25, 1995 ACM Member #____________

ACM/SIGDA Member 	US $320 			US $390

*Non-Member	        US $417				US $487

*If you are not an ACM/SIGDA member we are giving you the opportunity to 
join by paying your first year's dues out of your conference non-member 
registration fee -- a US$97 value. Forms will be available at on-site 
registration.

Guest Reception Tickets #Tickets______x US $15 ______
Guest Banquet Tickets #Tickets______x US $40 ______

Total Fees:____________________(Make checks payable to ACM/FPGA'95)
Payment Form (Circle Once)

AMEX 	MASTERCARD	 VISA	 CHECK

Credit Card#:_____________________
Exp. Date:________________________
Signature:________________________________________

Send Registration with payment to:

	FPGA `95, Colleen Matteis, 553 Monroe St., Santa Clara, CA. 95050, USA. 
	Phone: +1(408)296-6883 Fax: +1(408)296-5452.

For registration information contact Colleen Matteis, 
e-mail: sigda@nextwave.com. Cancellation must be in writing, and 
received by Colleen Matteis before January 24,1995.

		Hotel Information
		-----------------

The symposium will be held at the Monterey Marriott, 350 
Calle Principal, Monterey, CA 93940, USA. The phone 
number for room reservations is (408) 649-4234. 
Reservations must be made directly with the Hotel before 
January 20, 1995. Identify yourself with the group
Association for Computing Machinery FPGA `95 
Symposium to receive the special Symposium rates ($110 
single/double occupancy; parking is $10/day).

Directions to Hotel: From San Jose (a 1.5 hour trip), take 
HWY 101 South to HWY 156 west to HWY 1 South. On 
HWY 1 South, take the first exit in the city of Monterey 
(labelled Del Monte Ave.). Continue on Del Monte Ave. 
until the tenth traffic light. Stay in the left lane, and the 
hotel will be on the left. The hotel is the tallest building in 
the City of Monterey.

You can also fly directly to the Monterey Airport, which 
handles United, American and other air lines with at least 
8 flights per day.


Article: 593
Subject: Re: ViewLogic simulation without master reset
From: jnoll@su19bb.ess.harris.com (John Noll)
Date: Fri, 13 Jan 1995 23:15:25 GMT
Links: << >>  << T >>  << A >>

In article mk@newsbf02.news.aol.com, med440@aol.com (Med440) writes:
>... has fallen into my hands, and my very limited FPGA experience has already
> gotten me into trouble -- here goes: Many of the flip-flops in the
> current design do not have any reset/preset.  Because of this, predicting
> the state at power-on is impossible, as is generating the
> "print-on-change" type data required.   I don't think the lack of a master
> reset(or any reset) is a real problem from a design standpoint, as most of
> the FFs without resets are in clock-divider chains where state is not
> really an issue -- it's only from a simulation standpoint that this is
> troublesome.
> 
 
For what it's worth, I'm currently experiencing the same problem.  I'm designing
two Actel 1280A's using the Cadence tools and Rapidsim.  The problem is the same.
I have found that if you run the simulation long enough, sometimes the unknowns get
resolved (sometimes not)  also you might try checking to see of your simulator will
allow you to initialize gates (I can initialize them to all 0, all 1, postive logic
state, or negative state).  No method I have found is easy or works every time.  I
have always been succesful at resolving this problem by trial and error when doing
functional simulation.  HOWEVER, when doing back annotated timing simulation I have
had less luck.  I am at this very moment waiting for my design to load to see if
my next attempt will work.  I'll let you know how it goes.  My best advice would be
to contact someone who knows ViewLogic and see if they can find a way for you to 
initialize the unknown states.  I doubt if you'll get any solution from Actel, as you
have said, the part will work regardless of initialization state.

Best Luck.

John Noll jnoll@su19bb.ess.harris.com



Article: 594
Subject: FPGA tools that run on SGI ?
From: Rainer Malzbender <rainer@sdisplay.com>
Date: 14 Jan 1995 18:29:41 GMT
Links: << >>  << T >>  << A >>

We are about to get into FPGA design and would like to be able to use
both schematic entry (OrCAD on a PC) and VHDL. We like SGI
workstations, and would not want to migrate to Sun or HP for our other
work, so we'd be very interested in tools that run on SGI machines,
at least for the compute-intensive part of the design process (we
could live with transferring netlists from the PC). Is this a pipe
dream ? Thanks.


--
Rainer Malzbender
Senior Research Physicist
Displaytech, Inc.
2200 Central Ave.
Boulder, CO 80301
rainer@sdisplay.com
rainer@colorado.edu



Article: 595
Subject: Re: ViewLogic simulation without master reset
From: randraka@ids.net
Date: Sun, 15 Jan 95 07:25:33 GMT
Links: << >>  << T >>  << A >>
In Article <D2D9xq.MHt@news.ess.harris.com>
jnoll@su19bb.ess.harris.com (John Noll) writes:
>
>In article mk@newsbf02.news.aol.com, med440@aol.com (Med440) writes:
>>... has fallen into my hands, and my very limited FPGA experience has already
>> gotten me into trouble -- here goes: Many of the flip-flops in the
>> current design do not have any reset/preset.  Because of this, predicting
>> the state at power-on is impossible, as is generating the
>> "print-on-change" type data required.   I don't think the lack of a master
>> reset(or any reset) is a real problem from a design standpoint, as most of
>> the FFs without resets are in clock-divider chains where state is not
>> really an issue -- it's only from a simulation standpoint that this is
>> troublesome.
>> 
> 
>For what it's worth, I'm currently experiencing the same problem.  I'm designing
>two Actel 1280A's using the Cadence tools and Rapidsim.  The problem is the same.
>I have found that if you run the simulation long enough, sometimes the unknowns get
>resolved (sometimes not)  also you might try checking to see of your simulator will
>allow you to initialize gates (I can initialize them to all 0, all 1, postive logic
>state, or negative state).  No method I have found is easy or works every time.  I
>have always been succesful at resolving this problem by trial and error when doing
>functional simulation.  HOWEVER, when doing back annotated timing simulation I have
>had less luck.  I am at this very moment waiting for my design to load to see if
>my next attempt will work.  I'll let you know how it goes.  My best advice would be
>to contact someone who knows ViewLogic and see if they can find a way for you to 
>initialize the unknown states.  I doubt if you'll get any solution from Actel, as you
>have said, the part will work regardless of initialization state.
>
>Best Luck.
>
>John Noll jnoll@su19bb.ess.harris.com
>
I see this quite a bit since I usually don't use the async sets and clears and
use a synchronous reset only where it is essential. The way I usually get 
around this is by defining a vector containing the D inputs to the flops which
do not become known after your reset.  At the beginning of simulation, assign 
that vector to zero (or some other value) for one clock cycle then release the 
vector. This has the effect I believe you are looking for.  The viewlogic sim 
command file would contain something like:

v init <list of flops>
a init 0
c
r init

You will also want to make sure that your circuit really will start up from a 
random state.  If need be, you can simulate that by assigning different values 
to the init vector.

Hope this helps,

Ray Andraka
the Andraka Consulting Group
401/884-7930  FAX 401/884-7950
email randraka@ids.net

The Andraka Consulting Group is is digital design firm specializing in getting
the maximum performance from FPGAs.  Services include complete design,
development, simulation and integration of these devices.  We also evaluate,
troubleshoot and improve existing designs.


Article: 596
Subject: Re: ViewLogic simulation without master reset
From: bobe@soul.tv.tek.com (Bob Elkind)
Date: 16 Jan 1995 07:33:25 GMT
Links: << >>  << T >>  << A >>
To be more clear on the subject, the ASIC vendor does *not* want simulation
files.  The ASIC vendor wants fault test patterns to verify that the devices
were built correctly.

Simulation is what the designer does in the privacy of his/her "home" to
verify that the *design* is correct.  Fault testing is done by the foundry
to verify that the parts are *built* correctly.  By definition, any parts
that correctly pass the test pattern you give the foundry are good enough
for you to buy, whether or not they work in your circuit.

In sum, fault pattern generation and simulation pattern generation are very
different problems.

regards,

Bob Elkind, Tektronix TV Products, bobe@tv.tv.tek.com



Article: 597
Subject: Re: Xilinx marketing knuckleheads
From: bobe@soul.tv.tek.com (Bob Elkind)
Date: 16 Jan 1995 07:56:22 GMT
Links: << >>  << T >>  << A >>
dh@fncrd7.fnal.gov (don husby) writes (heavily edited! -- BE):

>The local Xilinx guy left a Xilinx brochure on my desk this morning 
>titled: "Xilinx 4000 vs. AT&T ORCA FPGAs: A feature comparison."

 <snip>

>The truthful comparison of logic capacity per CLB/PFU is:
>=========================================================================
>				X4000			ORCA 2C
>Fully covered functions:	5-bits			6-bits
>				1 independent FF	4 independent usable FF
                                ^
				| I think this is 2 independent FFs,
				| depending on your definition of the term
                                         
>Partially covered functions:	9-bits + 1 ind. FF	11-bits + 4 ind. FF
                                         ^
					 | again, I think this is 2!

>RAM capacity:			16x2			16x4
>RAM capacity:			32x1			32x2
>
>Plus ORCA has payed attention to making single PFU implementation of other
>functions:
>
>X4000	ORCA 2C
>-----------------
>2 CLB	1 PFU	Quad 2-1 multiplexer.
>2 CLB	1 PFU	Dual 4-1 mux with registered output. (ORCA uses a trick).
>		Each flip-flop has a multiplexed input that can select either 
>		the function generator or a direct input.  In addition to 
>		extending the logic capability for registered functions, this 
>		is intended to be used to create loadable counters:
>4 CLB?	1 PFU	4-bit loadable up/down counter with synchronous reset.
 ^
 | I believe this can be implemented with 2 CLBs, 2 bits per CLB, using the
 | fast carry and add/sub control features.  You may have to do a bit of
 | manual, custom macro layout work to do it, but that's life.

 <more snipped>

>Final note:
>  Xilinx also compares its software to AT&T's develompment system.  When I 
>called the local AT&T sales office, they recommended that I get NeoCad.  They 
>admit that NeoCad has more experience at this kind of software.  I've just 
>purchased a NeoCad system and find it superior in many ways (but not all) to 
>Xilinx.

I believe that ATT no longer offers a proprietary tool set.  I believe that
NeoCad is now the sole official vendor for Orca back-end tools.  I believe
that ATT recently made this decision (last half of 1994?) and that it's a
very good move on their part. I've done work with both Orca and Xilinx
(4K/3K) devices and toolsets, and I'm convinced that the hardware vendors
should leave the immense problem of SW toolset to a dedicated EECAD SW
vendor.

NeoCad has a good reputation, and they support Xilinx, Moto, and ATT/Orca
FPGAs with back-end (place/route/manual layout) tools.

  <balance snipped>

Bob Elkind, Tektronix TV Products,   bobe@tv.tv.tek.com


Article: 598
Subject: Re: PCB design with Xilinx
From: bobe@soul.tv.tek.com (Bob Elkind)
Date: 16 Jan 1995 08:21:36 GMT
Links: << >>  << T >>  << A >>
weathert@ee.umr.edu (Terry Chevalier) writes:
>	I am currently designing a board that is using both 240 pin and
>208 pin quadflat pack packages for the 4013 and 4010 xilinx chips
>respectively.  My problem is finding specifications for the design of
>the footprint of these chips.
  <snip>
>If anyone could point me to reference material to design the pads for
>these chips I would appreciate the time spent.
>William Eatherton

The latest Xilinx data book, 1994 *second edition*, contains all the
info you need, including the PCB pad layout dimensions, etc.

The previous 1994 data book had all the package info, but *not* the
PCB footprint info.

Also, the first 1994 databook has a note about "cavity up or cavity down"
in the packaging section.  There, it says that the ceramic quad flatpak
packages are all constructed "cavity down" to maximise heat flow from
the die to ambient air.  Make sure you understand that *ceramic* quad
flatpak does not equal *metal* quad flatpak, and all the metal quads
are indeed cavity *up*.  The largest 4K devices are not available in any
sort of cavity down (thermally better) surface mountable package.

I don't work/speak for Xilinx, I'm just a customer, and my opinions
should be subject to verification.

Bob Elkind, Tektronix TV Products, bobe@tv.tv.tek.com


Article: 599
Subject: Re: ViewLogic simulation without master reset
From: samson@ptd10c.erim.org (Joe Samson)
Date: 16 Jan 1995 13:19:52 GMT
Links: << >>  << T >>  << A >>
>sometimes the unknowns get resolved (sometimes not)  also you might try 
>checking to see of your simulator will allow you to initialize gates (I can 
>initialize them to all 0, all 1, postive logic state, or negative state).

I think that the real problem that the original poster is having is that 
because the flip-flops don't have resets, the device doesn't have predictable
outputs after reset, and so he can't generate test vectors for the
semi-custom fab line.
My only suggestion is to go back to the original design and put in some
resets - enough so that you can guarantee known outputs after some number
of clocks. If there isn't a spare input pin available for reset, maybe
you could use a combination of inputs to recognize a reset (for example,
if there were separate read and write enable inputs, having both asserted
simultaneously could be decoded as a reset).
--
+===============================================================+
+ Joe Samson                               (313) 994-1200 x2878 +
+ Research Engineer, ERIM                                       +
+ P.O. Box 134001                         email samson@erim.org +
+ Ann Arbor, MI 48113-4001                                      +
+===============================================================+




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