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Messages from 58600

Article: 58600
Subject: Partial Reconfiguration support for Spartan 2 or Spartan 2E devices
From: machosri@yahoo.com (Sriram)
Date: 28 Jul 2003 11:52:58 -0700
Links: << >>  << T >>  << A >>
hi , 
I have 2 major doubts.
The first one is whether Spartan 2 or Spartan 2E support partial
reconfiguration.

The second one is about the S/W support for partial reconfiguration.Is
there any support from XIlinx's Impact software to implement and
verify the same.
If not how would I go about implementing one.

Your answers to the above would be immensely helpful.

Thanks,
Sriram Anand

Article: 58601
Subject: Altera Stratix PCI board and Linux... Anyone try this?
From: skintigh_spam@yahoo.com (Seth)
Date: 28 Jul 2003 12:11:06 -0700
Links: << >>  << T >>  << A >>
Does anyone have any experience with this board, with or without Linux?

Thank you.

Article: 58602
Subject: help neede-----Error Pack 1107 -Unable to combine the following .........
From: paraagv@hotmail.com (paraag)
Date: 28 Jul 2003 12:30:19 -0700
Links: << >>  << T >>  << A >>
Hi 
im unable to comprehend this error inspite of the help given inthe
solution board.....im using ISE 5.2 version

ERROR:Pack:1107 - Unable to combine the following symbols into a
single IOB
   component:
   	BUF symbol "iobuf_6/IBUF" (Output Signal = dip_i<2>)
   	TBUF symbol "iobuf_6/OBUFT" (Control Signal = dip_t<2>)
   	PAD symbol "dip<2>" (Pad Signal = dip<2>)
   	PULL symbol "dip<2>_PULLUP" (Output Signal = dip<2>)
   Each of the following constraints specifies an illegal physical
site for a
   component of type IOB:
   	Symbol "dip<2>" (LOC=AB9)
   Please correct the constraints accordingly.
ERROR:Pack:1107 - Unable to combine the following symbols into a
single IOB
   component:
   	BUF symbol "iobuf_7/IBUF" (Output Signal = dip_i<3>)
   	TBUF symbol "iobuf_7/OBUFT" (Control Signal = dip_t<3>)
   	PAD symbol "dip<3>" (Pad Signal = dip<3>)
   	PULL symbol "dip<3>_PULLUP" (Output Signal = dip<3>)
   Each of the following constraints specifies an illegal physical
site for a
   component of type IOB:
   	Symbol "dip<3>" (LOC=AB8)
   Please correct the constraints accordingly.
Problem encountered during the packing phase.

can anyone help me on this.
Paraag

Article: 58603
Subject: Re: help neede-----Error Pack 1107 -Unable to combine the following .........
From: "Avrum" <avrum@REMOVEsympatico.ca>
Date: Mon, 28 Jul 2003 15:58:16 -0400
Links: << >>  << T >>  << A >>
I have never encountered these messages before, but from them, it looks like
you are trying to pack an input buffer (IBUF) and a tristateable output
buffer (OBUFT) into the same IOB; specifying the same LOC constraint on the
IBUF and the OBUFT. If this is the case, then you should be using an IOBUF
instead of the IBUF and OBUFT.

Avrum

"paraag" <paraagv@hotmail.com> wrote in message
news:39fdcd07.0307281130.1d418106@posting.google.com...
> Hi
> im unable to comprehend this error inspite of the help given inthe
> solution board.....im using ISE 5.2 version
>
> ERROR:Pack:1107 - Unable to combine the following symbols into a
> single IOB
>    component:
>    BUF symbol "iobuf_6/IBUF" (Output Signal = dip_i<2>)
>    TBUF symbol "iobuf_6/OBUFT" (Control Signal = dip_t<2>)
>    PAD symbol "dip<2>" (Pad Signal = dip<2>)
>    PULL symbol "dip<2>_PULLUP" (Output Signal = dip<2>)
>    Each of the following constraints specifies an illegal physical
> site for a
>    component of type IOB:
>    Symbol "dip<2>" (LOC=AB9)
>    Please correct the constraints accordingly.
> ERROR:Pack:1107 - Unable to combine the following symbols into a
> single IOB
>    component:
>    BUF symbol "iobuf_7/IBUF" (Output Signal = dip_i<3>)
>    TBUF symbol "iobuf_7/OBUFT" (Control Signal = dip_t<3>)
>    PAD symbol "dip<3>" (Pad Signal = dip<3>)
>    PULL symbol "dip<3>_PULLUP" (Output Signal = dip<3>)
>    Each of the following constraints specifies an illegal physical
> site for a
>    component of type IOB:
>    Symbol "dip<3>" (LOC=AB8)
>    Please correct the constraints accordingly.
> Problem encountered during the packing phase.
>
> can anyone help me on this.
> Paraag



Article: 58604
Subject: Re: CRC questions
From: "Glen Herrmannsfeldt" <gah@ugcs.caltech.edu>
Date: Mon, 28 Jul 2003 21:13:58 GMT
Links: << >>  << T >>  << A >>

"Marc Randolph" <mrand@my-deja.com> wrote in message
news:15881dde.0307280821.fba8a71@posting.google.com...

(snip)

> > I am not sure why it is that way, but it is.   I don't completely
understand
> > the process for generating primitive polynomials.  My understanding is
that
> > it gets harder as they get bigger.  It might be that someone found some
> > relatively simple large ones that work well enough.
>
> I suspect that is the case.
>
> http://www.cs.ucl.ac.uk/staff/d.jones/crcnote.pdf
>
> discusses how the "sparse" 64-bit polynomial produced an abnormally
> high rate of collisions when used as a simple hash.  Yes, I know it
> even a "good" CRC isn't really a good hash function, but that seem to
> be what they were using it as.

Some years ago I was using it for a DNA hash function.  Since EMBL had
already used it, I decided to use it, too.

Though even with the results they have, it is significantly better than
CRC32.   Because of the sparse ones it was very easy to implement using 32
bit arithmetic, which I considered an advantage.

-- glen



Article: 58605
Subject: Replacing Spartan 300E by 600E
From: electronics_designer@hotmail.com (Roel)
Date: 28 Jul 2003 16:37:16 -0700
Links: << >>  << T >>  << A >>
Hi,

I checked the "Pin Compatibility tool" of xilinx for the spartan IIE
http://www.xilinx.com/applications/web_ds_sp2e/pin_comp/

When I compare the 300E with the 600E in FG456 package then I got 
a few mismatches. Pins that are "NC" for 300E and should be either GND
or VCCINT for the 600E type. The design did not anticipate for the
600E so the "NC's" are really not connected. Can someone tell me if
this will be a problem?

Thanks,
R_ed

Article: 58606
Subject: Re: xilinx programing interface
From: email_address@message.end
Date: Mon, 28 Jul 2003 23:52:19 GMT
Links: << >>  << T >>  << A >>
Hi Peter,

Speaking of configuration, can I bug you about data sheets?

I really want to design in an XCF16P, but I can't find the data sheet.

The link provided gets you a PDF that stops at XCF04P.  (Different
package and everything. ;)

Or is the part not "real" yet?

Thanks,
Gary
g w helbig -at- yahoo -dot- com

On Mon, 28 Jul 2003 09:17:28 -0700, Peter Alfke <peter@xilinx.com>
wrote:

>Michael, what do you mean by interface? Read the data sheet, and it
>tells you that you have to input a serial bitstream, and you can store
>this in many ways. The "interface" is the simplest possible, a data line
>and a clock.
>Peter Alfke, Xilinx
>
>Michael Petry wrote:
>> 
>> Hello,
>>  I'm looking for a programing interface (cheap, selfmade)for a xilinx FPGA
>> (e.g. XCS10-3). Does anybody know some links for a interface?
>>  Thanks
>>  Michael


Article: 58607
Subject: Re: xilinx programing interface
From: email_address@message.end
Date: Mon, 28 Jul 2003 23:55:17 GMT
Links: << >>  << T >>  << A >>

Two options I can think of:

I see JTAG programmers on eBay for $15.  Search for Xilinx or Altera;
the JTAG interfaces are compatable.

I program my spartan with I/O bits on the CPU (that just happens to be
on the card).  It's not that tough.  20 lines of PERL to convert the
bit file, and another 20 lines of assembler to move it out to the
chip.

Gary.
g w helbig -at- yahoo -dot- com

On Mon, 28 Jul 2003 14:13:39 +0200, Michael Petry <micpetry@web.de>
wrote:

>
>Hello,
> I'm looking for a programing interface (cheap, selfmade)for a xilinx FPGA 
>(e.g. XCS10-3). Does anybody know some links for a interface?
> Thanks
> Michael
>


Article: 58608
Subject: Re: help neede-----Error Pack 1107 -Unable to combine the following
From: Marc Guardiani <marc@guardiani.com>
Date: Mon, 28 Jul 2003 21:07:43 -0400
Links: << >>  << T >>  << A >>
Also make sure that the specified pin is legal. For example, you can't 
define an output on a global clock input pin.

Avrum wrote:
> I have never encountered these messages before, but from them, it looks like
> you are trying to pack an input buffer (IBUF) and a tristateable output
> buffer (OBUFT) into the same IOB; specifying the same LOC constraint on the
> IBUF and the OBUFT. If this is the case, then you should be using an IOBUF
> instead of the IBUF and OBUFT.
> 
> Avrum
> 
> "paraag" <paraagv@hotmail.com> wrote in message
> news:39fdcd07.0307281130.1d418106@posting.google.com...
> 
>>Hi
>>im unable to comprehend this error inspite of the help given inthe
>>solution board.....im using ISE 5.2 version
>>
>>ERROR:Pack:1107 - Unable to combine the following symbols into a
>>single IOB
>>   component:
>>   BUF symbol "iobuf_6/IBUF" (Output Signal = dip_i<2>)
>>   TBUF symbol "iobuf_6/OBUFT" (Control Signal = dip_t<2>)
>>   PAD symbol "dip<2>" (Pad Signal = dip<2>)
>>   PULL symbol "dip<2>_PULLUP" (Output Signal = dip<2>)
>>   Each of the following constraints specifies an illegal physical
>>site for a
>>   component of type IOB:
>>   Symbol "dip<2>" (LOC=AB9)
>>   Please correct the constraints accordingly.
>>ERROR:Pack:1107 - Unable to combine the following symbols into a
>>single IOB
>>   component:
>>   BUF symbol "iobuf_7/IBUF" (Output Signal = dip_i<3>)
>>   TBUF symbol "iobuf_7/OBUFT" (Control Signal = dip_t<3>)
>>   PAD symbol "dip<3>" (Pad Signal = dip<3>)
>>   PULL symbol "dip<3>_PULLUP" (Output Signal = dip<3>)
>>   Each of the following constraints specifies an illegal physical
>>site for a
>>   component of type IOB:
>>   Symbol "dip<3>" (LOC=AB8)
>>   Please correct the constraints accordingly.
>>Problem encountered during the packing phase.
>>
>>can anyone help me on this.
>>Paraag
> 
> 
> 

-- 


Marc Guardiani

To reply directly to me, use the address given below. The domain name is 
phonetic.
fpgaee81-at-eff-why-eye-dot-net


Article: 58609
Subject: Spartan IIE max pin switching
From: "Gaby Jay" <gabsterblue@hotmail.com>
Date: Mon, 28 Jul 2003 21:45:15 -0400
Links: << >>  << T >>  << A >>
Hi,

    I've been unable to determine looking in the datasheet what is the
fastest an output pin can switch on a Xilinx Spartan IIE. Info appreciated.

thx



Article: 58610
Subject: Re: VHDL Book Recommendations Please
From: "Paul Leventis" <paul.leventis@utoronto.ca>
Date: Tue, 29 Jul 2003 01:49:36 GMT
Links: << >>  << T >>  << A >>
> How specific to Altera is this book?

Not at all.  It ships with MaxPlus II (or maybe Quartus in the newer
editions?) and occasionally gives tutorials or examples that can be done in
the CAD tool.  But the vast majority of the text and VHDL examples use only
the IEEE libraries.  One place where an Altera-specific reference would be
made (for example) is when describing the capabilities of CAD tools, such as
parameterized modules (in this case, Altera's LPMs such as lpm_add_sub,
etc).  The concepts are portable to other tools.

Looking through the book again for the first time in a few years, my take on
it is that it is first a book about digital design (intro to digitial logic,
arithmetic techniques, FSMs, etc.) and only an intro to VHDL, with the most
useful/basic subset of the language introduced.  Once you go through that
book, a more thorough reference on the VHDL itself would be useful to flush
out your knowledge of the complete language.  And a more advanced textbook
on particular areas of digital design (such as arithmetic) may be needed.

Regards,

Paul Leventis
Altera Corp.





Article: 58611
Subject: Re: Replacing Spartan 300E by 600E
From: Andrew Paule <lsboogy@qwest.net>
Date: Mon, 28 Jul 2003 21:01:35 -0500
Links: << >>  << T >>  << A >>
Hi Roel:

in my experience, this will be a problem  - if it's not in a bga, you 
should be able to pull acceptable rework with good results until you can 
spin the board.

Andrew

Roel wrote:

>Hi,
>
>I checked the "Pin Compatibility tool" of xilinx for the spartan IIE
>http://www.xilinx.com/applications/web_ds_sp2e/pin_comp/
>
>When I compare the 300E with the 600E in FG456 package then I got 
>a few mismatches. Pins that are "NC" for 300E and should be either GND
>or VCCINT for the 600E type. The design did not anticipate for the
>600E so the "NC's" are really not connected. Can someone tell me if
>this will be a problem?
>
>Thanks,
>R_ed
>  
>


Article: 58612
Subject: Re: VHDL Book Recommendations Please
From: rickman <spamgoeshere4@yahoo.com>
Date: Tue, 29 Jul 2003 00:01:27 -0400
Links: << >>  << T >>  << A >>
Jon Masters wrote:
> 
> Hi,
> 
> I am after a book with a title something along the lines of
> 
> ``VHDL for Software Engineers''
> 
> Finding a suitable book seems pretty challenging as most assume either
> the reader is an experienced electrical engineer or that they are a
> complete novice coming in. I have years of Computer Science background
> and am trying to become more aquainted with the actual hardware design.
> 
> FWIW the Linux port I mentioned before has now progressed further and I
> am in the process of adding support for various Xilinx devices.
> 
> Jon.

I see you have gotten a lot of recomendations that don't really address
your question.  If you are a software engineer and are not familiar with
hardware design, I recommend that you start with some good books on
hardware before you try to master a hardware desciption language.  My
observations have been that you will not do well with hardware
desciption languages if you don't understand the hardware you want to
describe.  

I personally think that too many engineers try to write in HDL in
similar ways to writing software.  The two are very different and have
little in common.  You can write an HDL program in a similar manner to
software, but you will often get a very inefficient implementation and
it is very likely that the design will not work well if you do not
observe many rules of hardware design that have nothing to do with the
HDL.  

I can't recommend a good starter book in hardware design since all of
the books I read are quite old and most were not very good as a
beginner's book.  Perhaps someone else can recommend a good book for
teaching hardware design to a software person?  

-- 

Rick "rickman" Collins

rick.collins@XYarius.com
Ignore the reply address. To email me use the above address with the XY
removed.

Arius - A Signal Processing Solutions Company
Specializing in DSP and FPGA design      URL http://www.arius.com
4 King Ave                               301-682-7772 Voice
Frederick, MD 21701-3110                 301-682-7666 FAX

Article: 58613
Subject: Re: Spartan IIE max pin switching
From: russelmann@hotmail.com (Rudolf Usselmann)
Date: 28 Jul 2003 22:57:06 -0700
Links: << >>  << T >>  << A >>
"Gaby Jay" <gabsterblue@hotmail.com> wrote in message news:<ECkVa.12678$vB6.409940@weber.videotron.net>...
> Hi,
> 
>     I've been unable to determine looking in the datasheet what is the
> fastest an output pin can switch on a Xilinx Spartan IIE. Info appreciated.
> 
> thx


The reason you where not able to determine this is
probably because it is a function of the pin loading
and output duffer size. You have to look a bit closer
through the tables in the data sheet, select an output
buffer type, strength and then calculate the max delay
for a given load.

Regards,
rudi               
--------------------------------------------------------
www.asics.ws  --- Solutions for your ASIC/FPGA needs ---
----------------- FPGAs * Full Custom ICs * IP Cores ---
FREE IP Cores --> http://www.asics.ws/ <-- FREE IP Cores

Article: 58614
Subject: how to design hardware for 2's complement parallel multiplier(at gate level)
From: rsprasad24@yahoo.co.in (prasad)
Date: 28 Jul 2003 23:35:11 -0700
Links: << >>  << T >>  << A >>
I am designing QAM chip.
I want know hardware for 2's complement parallel multiplier(12bit by 12 bit).
can any body know plz help me.
  Thank you and best regards.
                                  prasad

Article: 58615
Subject: Re: VHDL Book Recommendations Please
From: "Jonathan Bromley" <jonathan@oxfordbromley.u-net.com>
Date: Tue, 29 Jul 2003 09:45:36 +0100
Links: << >>  << T >>  << A >>
"rickman" <spamgoeshere4@yahoo.com> wrote in message
news:3F25F197.818731BA@yahoo.com...
> Jon Masters wrote:
> > I am after a book with a title something along the lines of
> > ``VHDL for Software Engineers''
> > Finding a suitable book seems pretty challenging [...]

> I see you have gotten a lot of recomendations that don't really address
> your question.  If you are a software engineer and are not familiar with
> hardware design, I recommend that you start with some good books on
> hardware before you try to master a hardware desciption language.  My
> observations have been that you will not do well with hardware
> desciption languages if you don't understand the hardware you want to
> describe.

Too true.

> I personally think that too many engineers try to write in HDL in
> similar ways to writing software.  The two are very different and have
> little in common.
This I'm less sure about.  It is certainly true that some people try to
slide straight from software into designing hardware, and spectacularly
miss the point.  But it is also true that many hardware engineers miss
the opportunity to learn from software techniques when writing VHDL.
This is especially true when creating non-synthesisable code, for
test benches or component modelling.

> You can write an HDL program in a similar manner to
> software, but you will often get a very inefficient implementation and
> it is very likely that the design will not work well if you do not
> observe many rules of hardware design that have nothing to do with the
> HDL.

Again, if you are trying to create synthesisable hardware, this is
entirely true.

And to return to the question...

I quite like Mark Zwolinski's book "Digital System Design with VHDL"
(Prentice-Hall).  It's aimed at undergraduates but it's very clear
and good to read, and quite focused about what does and doesn't
make sensible hardware.  If you are really interested in creating
hardware, you may also care to look at Andrew Rushton's "VHDL for
Logic Synthesis" (Wiley);  personally I like the style, and it's
particularly good on design for synthesis.

If you are a real software person, with a good background in
computer science, then you probably need to know a few things
that they don't usually tell you in beginners' VHDL books.

- Never, never forget that hardware is a STATICALLY DETERMINED
  network of heterogeneous, fine-grained processing elements
  which typically fall into two categories:  combinational
  (output is a pure function of the inputs, delay is short(ish)
  compared with the system clock period) and register (output
  captures a new value on the active edge of the system clock,
  then holds it until the next active edge).  If you try to
  do anything that implies a dynamically varying network of
  processes, synthesis will need to map it on to a specific
  static network which is likely to be very inefficient.

- VHDL is built around a discrete-event simulation model.
  However, it's commonly used to create cycle-based,
  clock-synchronous systems.  Getting from one paradigm
  to the other requires the application of some discipline
  so that all the hardware you create matches the synchronous
  model.  Find out about "synthesis templates".

- You can write ordinary procedural software in VHDL if you
  wish, but you only get real value out of VHDL if you use
  it to create a network of interacting processes.

- VHDL is strongly typed, and obsessive about static
  compile-time checks.  This often leads to what many
  perceive to be excessive verbosity.

- VHDL uses a library-based mechanism of compilation that
  follows Ada's model.  This is really important if you are
  using a simulator; it's less troublesome for synthesis,
  because most synthesis tools recompile everything from
  source every time they run.

Enjoy,
--
Jonathan Bromley, Consultant

DOULOS - Developing Design Know-how
VHDL * Verilog * SystemC * Perl * Tcl/Tk * Verification * Project Services

Doulos Ltd. Church Hatch, 22 Market Place, Ringwood, Hampshire, BH24 1AW, UK
Tel: +44 (0)1425 471223                    mail: jonathan.bromley@doulos.com
Fax: +44 (0)1425 471573                           Web: http://www.doulos.com

The contents of this message may contain personal views which
are not the views of Doulos Ltd., unless specifically stated.




Article: 58616
Subject: Re: Spartan IIE max pin switching
From: antti@case2000.com (Antti Lukats)
Date: 29 Jul 2003 03:28:48 -0700
Links: << >>  << T >>  << A >>
Virtex-E highest speed is capable of 622MB/s data transfer in LVDS DDR mode
those clock is running at 311MHz
if the S2E speed grade -7 has similar AC characteristics as VirtexE -7
then the answer to your question would be 'just above 300MHz'

but sure it all depends on the load and standard selected.

antti


russelmann@hotmail.com (Rudolf Usselmann) wrote in message news:<d44097f5.0307282157.47edf1a6@posting.google.com>...
> "Gaby Jay" <gabsterblue@hotmail.com> wrote in message news:<ECkVa.12678$vB6.409940@weber.videotron.net>...
> > Hi,
> > 
> >     I've been unable to determine looking in the datasheet what is the
> > fastest an output pin can switch on a Xilinx Spartan IIE. Info appreciated.
> > 
> > thx
> 
> 
> The reason you where not able to determine this is
> probably because it is a function of the pin loading
> and output duffer size. You have to look a bit closer
> through the tables in the data sheet, select an output
> buffer type, strength and then calculate the max delay
> for a given load.
> 
> Regards,
> rudi               
> --------------------------------------------------------
> www.asics.ws  --- Solutions for your ASIC/FPGA needs ---
> ----------------- FPGAs * Full Custom ICs * IP Cores ---
> FREE IP Cores --> http://www.asics.ws/ <-- FREE IP Cores

Article: 58617
Subject: Re: Pricing question....
From: wpiman@aol.com (MS)
Date: 29 Jul 2003 06:44:33 -0700
Links: << >>  << T >>  << A >>
We got a ball park cost for our timeframe and volume.  I should have
said this up front.

Yeah- I knew it would be a wild guess- the drop in the price of
processor is probably a safe model to follow.

Thanks to everyone- including the vendors----

MS

Article: 58618
Subject: Re: Spartan IIE max pin switching
From: Austin Lesea <Austin.Lesea@xilinx.com>
Date: Tue, 29 Jul 2003 07:31:55 -0700
Links: << >>  << T >>  << A >>
All,

Please take advantage of the fact that we have IBIS models, and there are IBIS simulators out there!

Any such question can be easily answered by simulating the IO standard, the pcb traces, and the loading at the end of
the traces.

If you need a "what if" answer, you may open a case with our hotline, but you need to state:

- the io standard
- the pcb trace lengths/impedances/topology
- the load (IBIS models of the load - where are they if they are not Xilinx models)
- SDR or DDR

Austin

Antti Lukats wrote:

> Virtex-E highest speed is capable of 622MB/s data transfer in LVDS DDR mode
> those clock is running at 311MHz
> if the S2E speed grade -7 has similar AC characteristics as VirtexE -7
> then the answer to your question would be 'just above 300MHz'
>
> but sure it all depends on the load and standard selected.
>
> antti
>
> russelmann@hotmail.com (Rudolf Usselmann) wrote in message news:<d44097f5.0307282157.47edf1a6@posting.google.com>...
> > "Gaby Jay" <gabsterblue@hotmail.com> wrote in message news:<ECkVa.12678$vB6.409940@weber.videotron.net>...
> > > Hi,
> > >
> > >     I've been unable to determine looking in the datasheet what is the
> > > fastest an output pin can switch on a Xilinx Spartan IIE. Info appreciated.
> > >
> > > thx
> >
> >
> > The reason you where not able to determine this is
> > probably because it is a function of the pin loading
> > and output duffer size. You have to look a bit closer
> > through the tables in the data sheet, select an output
> > buffer type, strength and then calculate the max delay
> > for a given load.
> >
> > Regards,
> > rudi
> > --------------------------------------------------------
> > www.asics.ws  --- Solutions for your ASIC/FPGA needs ---
> > ----------------- FPGAs * Full Custom ICs * IP Cores ---
> > FREE IP Cores --> http://www.asics.ws/ <-- FREE IP Cores


Article: 58619
Subject: Re: VHDL Book Recommendations Please
From: Mike Treseler <tres@tc.fluke.com>
Date: Tue, 29 Jul 2003 08:10:20 -0700
Links: << >>  << T >>  << A >>
Jonathan Bromley wrote:

> This I'm less sure about.  It is certainly true that some people try to
> slide straight from software into designing hardware, and spectacularly
> miss the point.  But it is also true that many hardware engineers miss
> the opportunity to learn from software techniques when writing VHDL.
> This is especially true when creating non-synthesisable code, for
> test benches or component modelling.

Well said.

Some of that computer science stuff
can be applied to synthesis as well.
References to constant data structures or
well named functions can replace
"magic numbers" in synth code.

Recurring sets of sequential statements
can be replaced with a procedure.

           -- Mike Treseler


Article: 58620
Subject: Re: FPGA research
From: "Steve Casselman" <sc_nospam@vcc.com>
Date: Tue, 29 Jul 2003 16:14:40 GMT
Links: << >>  << T >>  << A >>
> BTW, what is the difference between academic and industrial research ?
>
About $75K/year.

If you just want to see what the hot research topics are go to
http://fccm.org and http://fpl.org .
Also http://fpga.org has lots of info as well as http://www.optimagic.com

Steve



Article: 58621
(removed)


Article: 58622
Subject: Re: FPGA research
From: Austin Lesea <Austin.Lesea@xilinx.com>
Date: Tue, 29 Jul 2003 11:17:35 -0700
Links: << >>  << T >>  << A >>
Steve,

Good one.  I always thought the difference was between generating degrees,
and generating $$$ (both useful and necessary).

Austin

Steve Casselman wrote:

> > BTW, what is the difference between academic and industrial research ?
> >
> About $75K/year.
>
> If you just want to see what the hot research topics are go to
> http://fccm.org and http://fpl.org .
> Also http://fpga.org has lots of info as well as http://www.optimagic.com
>
> Steve


Article: 58623
Subject: Re: VHDL Book Recommendations Please
From: Eric Crabill <eric.crabill@xilinx.com>
Date: Tue, 29 Jul 2003 13:00:59 -0700
Links: << >>  << T >>  << A >>

Hi,

I entirely agree.  The way you teach hardware design
to a software person should be the same way you teach
it to an EE undergraduate.

I would think any introductory digital design text
would be a good start, there is one by M. Morris
Mano, and another by John F. Wakerly.  There are,
no doubt, countless others.  Amazon might be a good
place to start looking.

Eric

rickman wrote:
> 
> Jon Masters wrote:
> >
> > Hi,
> >
> > I am after a book with a title something along the lines of
> >
> > ``VHDL for Software Engineers''
> >
> > Finding a suitable book seems pretty challenging as most assume either
> > the reader is an experienced electrical engineer or that they are a
> > complete novice coming in. I have years of Computer Science background
> > and am trying to become more aquainted with the actual hardware design.
> >
> > FWIW the Linux port I mentioned before has now progressed further and I
> > am in the process of adding support for various Xilinx devices.
> >
> > Jon.
> 
> I see you have gotten a lot of recomendations that don't really address
> your question.  If you are a software engineer and are not familiar with
> hardware design, I recommend that you start with some good books on
> hardware before you try to master a hardware desciption language.  My
> observations have been that you will not do well with hardware
> desciption languages if you don't understand the hardware you want to
> describe.
> 
> I personally think that too many engineers try to write in HDL in
> similar ways to writing software.  The two are very different and have
> little in common.  You can write an HDL program in a similar manner to
> software, but you will often get a very inefficient implementation and
> it is very likely that the design will not work well if you do not
> observe many rules of hardware design that have nothing to do with the
> HDL.
> 
> I can't recommend a good starter book in hardware design since all of
> the books I read are quite old and most were not very good as a
> beginner's book.  Perhaps someone else can recommend a good book for
> teaching hardware design to a software person?
> 
> --
> 
> Rick "rickman" Collins
> 
> rick.collins@XYarius.com
> Ignore the reply address. To email me use the above address with the XY
> removed.
> 
> Arius - A Signal Processing Solutions Company
> Specializing in DSP and FPGA design      URL http://www.arius.com
> 4 King Ave                               301-682-7772 Voice
> Frederick, MD 21701-3110                 301-682-7666 FAX

Article: 58624
Subject: SRAM question in Cyclone Dev. Board
From: "SDL" <S.DeLuca@nospamUSA.NET>
Date: Tue, 29 Jul 2003 20:09:11 GMT
Links: << >>  << T >>  << A >>
Hi,
Can I decide the address of some variables  in the SRAM of Altera Cyclone
Development board? In which way  I can reserve an area for them, from my
Nios C code?
Tanks
Salvo






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