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Re: FPGA Journal Article
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I can't claim to know the economics of hobbyists elsewhere in the world,
but IMNSHO in the US, someone who can't afford to spend USD $99 on
something needed for their hobby doesn't realy qualify as a "hobbyist".
People routinely spend orders of magnitude more than that on hobbies
other than electronics.

And yes, I remember back when I was a starving college student.  Even
then I managed to spend much more than $99/year on hobby items, though
perhaps I shouldn't have.

One guy I knew back then complained that he couldn't afford a $100
computer (a Timex/Sinclair or the like), even though he typically spent
well over $100 per month on accessorizing his sports car.  It's a matter
of priorities.

Re: FPGA Journal Article

I'll start by saying I represent manufacturer making low cost boards but I
can pass offline some of the feedback we get from users of our products
particularly our Raggedstone1 and low cost modules that we sell also.
Generally I would say that the fact that FPGA boards like ours now cost less
that it takes to fill my car with fuel so that the start-up cost is nearly
inconsequential to most hobby engineers. Coupled to that you get free fully
function tools from most silicon vendors, and that achieving timing in
designs at frequencies below say 50MHz is now easy, the marriage of factors
is allowing hobbyists to use the technology. Looking back to say 10 years
ago most of these factors didn't exist or were very limited and the barrier
to hobby use was hugh. I can be contacted through our support email or
telephone number, available on our website, if you want a bit more feedback.

John Adair
Enterpoint Ltd. - Home of Raggedstone1. The Low Cost Spartan3 PCI
Development Board.

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Re: FPGA Journal Article
On 12 Jan 2006 12:15:13 -0800, "Kevin Morris"

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I *used* to be an electronics hobbyist, but now I do it full-time.

The trend here is increasingly towards digital and software,
increasingly away from actual electricity. The tools of choice become
PCs and green eyeshades, same as the gear needed to be an accountant.

This is partly because it's less messy, and because universities can
replace expensive lab benches and test equipment with cheap laptop PCs
that the students have to buy themselves. Hell, you can get an "EE"
degree now without studying electromagnetics!

I walked through the EE department at Cornell and counted screens. PC
screens outnumbered oscilloscope screens by about 6:1.

That's fine by me: I design instrumentation that's analog intense, and
the uPs and FPGAs play supporting roles. But a lot of kids are missing
the luxury boat if the only numbers they know how to count are 0 and


Re: FPGA Journal Article
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Hi John,
I design the same stuff. However, I find I'm using my PC more and more.
Simulating it and getting the design right first spin is much nicer than
fixing it later, at least that's what the CEO says. I have software on my PC
that (I hear) uses lots of 0's and 1's together to model real numbers.
Lovely! ;-)
Cheers, Syms.
p.s. But you're right. I don't own a boat.

Re: FPGA Journal Article

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So, I wonder, how many people here are exclusively logic designers,
and how many are more general EEs, who deal with the analog, power,
thermal, and other aspects of electronic design?


Re: FPGA Journal Article

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I've never worked with any "exclusively logic designers".  (At
least I don't think I have.  Maybe one snuck in that I didn't

There is also the other end of the spectrum: firmware/drivers/software.
For most projects that I've worked on, that's a cricital
part of the big picture.

You could also expend up to system architecture and stuff like that.

The suespammers.org mail server is located in California.  So are all my
other mailboxes.  Please do not send unsolicited bulk e-mail or unsolicited
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Re: FPGA Journal Article
Hello Kevin,

You are welcome to contact me directly.  You know what they say about
opinions...  I have one, too.  You can check out my hobby-ish activites

http://www.fpga-games.com (self-funded hobby)
http:///www.engr.sjsu.edu/crabill (some funds from Ahhhnold and the
State of California)

I'm standing on the shoulders of great people like Mr. Mike J from FPGA
Arcade over at:


Also, I think another very interesting product for recreational
learning is the XGS, see:


Of course, you could implement the whole XGS in a small FPGA, but for
someone with a CS background (or none at all) a product like the XGS
might be a very enticing first step into the world of electronics.

Eric Crabill
Speaking for Myself

Re: FPGA Journal Article
Thank you for the kind words Eric.
P.S. has everyone read Eric's article about FPGA Gaming in XCELL?

Re: FPGA Journal Article

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Well, I'm not really a hobbyist, but a VERY small business (just me, and
a part-timer to help solder boards.)  But, the level of stuff I'm doing
(in my home
business) is maybe close to hobby level.  You might look at my web pages on
that project, and see if it is of interest :
All of the "control" or "controller" products have at least one FPGA in
The PPMC has one FPGA and 2 CPLDs for the basic set.  No way could I have
done these without FPGAs.  I have never used a development board, just
ahead with my best guess of what the prototype should look like.  And,
just 2-layer
boards, too.


Re: FPGA Journal Article

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I think it is not true. Hobbyists do not need state-of-the-art technology,
they need satisfaction -- this is the key difference compared to
electronics. For one person a simple LED blinker is perfectly enough,
somebody else is happy when his three transistor AM radio is working,
there also are hobbyists doing DSP using FPGAs just for fun.

The next problem is related with the lack of appropriate technologies.
SMD parts were useless, because we didn't know how to produce
good enough single layer PCBs at home, not to mention double layer
boards. Now we have two competitive technologies (optical, based on
photoactive resins and the second one, called "thermotransfer", which
directly transfers the pattern from a sheet of paper printed by a laser
printer onto the copper surface using a flatiron and two rags). We've
even learned how to make precise two-sided PCBs using that technologies.
Now the SMD components in TQFP/SO/TSSOP are no longer a
problem. But we still don't know how to solder BGAs and QFNs...

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I think that kits are a big misunderstanding, because you just need to
connect provided parts as described on a provided diagram. Even
a chimp could do it. The trick is to design the device yourself, from
scratch. It needn't be perfect, it sometimes produces smoke, but it's

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Hmm, really? ;-) As far as I know the only "pure" hobbyists
here are Antti and myself, the rest is more or less professional.

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Hard to obtain in small quantities...

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But they do not  provide free simulators, so they are virtually useless for

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Well, I hope it's useful... . :-)

    Best regards
    Piotr Wyderski

"If you were plowing a field, which would you rather use?
Two strong oxen or 1024 chickens?" -- Seymour Cray

Re: FPGA Journal Article
On Sat, 14 Jan 2006 01:55:00 +0100, "Piotr Wyderski"

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But you want something for kids to build when they're young, before
they're capable of designing something themselves.  Lots of us cut our
teeth on the 50-in-1 sets and Heathkits.

If a kid between the ages of 8 and 15 asked me how to get started in
electronics, I'd:

1) send them to Ramsey Electronics
(http://www.ramseyelectronics.com /), which makes nice, relatively
inexpensive kits of varying complexity.

2) ask them to get off my lawn.  (Sort of obligatory at my age.)

Bob Perlman
Cambrian Design Works  

Re: FPGA Journal Article

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There are many of us here who started out as pure hobbyists, but then
grew our passion into a paying endeavor.  I started out in the mid '70's
first with dissected radios, tape recorders etc, whatever I could get my
hands on, with radio shack kits (many of which I heavily modified...one
that comes to mind was a regulated power supply where the 2N3055 got hot
enough to melt through the red plastic board/box that soon got a
heatsink and a darlington pair for more output current and a switch to
select output voltages).  From there, I started getting into logic.
Between a 1976 Signetics IC databook (which is still on my bookshelf)
and several of Lancaster's cookbooks (some of his circuits would never
get past a critical review, but they were great for learning) I taught
myself digital design.   Even built a couple of computers based on the
then brand new 6800 (on an Ohio Scientific board), and then the Z-80
scratch built on wire-wrap boards before graduating from high school in

Like Philip said, I had a mentor (a friend of the family who is an EE
and was consulting mostly in audio and telephony back in the 60's and
70's) that gave me much of the motivation to make and improve on the
projects in Radio Electronics (which I was subscribed to from 1971 to
1982, I dumped the entire collection when it caused me to exceed my
weight allowance in a move with the Air Force, Killed me, but I couldn't
even give them away).

Re: FPGA Journal Article
I built radios in high-school days, and was a ham operator during
college years. Later, in Sweden, I designed and built power supplies
and sold a hundred of them as a moonlight operation. Then the usual
audio amplifiers and speaker boxes.
Now the interest is rekindled and I play with the design of my
second-generation programmable clock module (1 Hz to 2.5 GHz with,
hopefully, 30 ps jitter). But this also taught me that, for top-notch
performance, you need the help of several friends and experts (software
design, pc-board lay-out, GHz trickery, test instrumentation) and of a
commercial manufacturer. We built a few hundred of the first generation
"X-Pod", and are using them inside the company on many test benches. So
it's more "skunk works" than hobby activity, but still the same fun.
I have toyed with the idea of a storage scope. The digital part in an
FPGA plus external RAM looks easy. But less than 500 MHz sample rate
seems to make it a toy, and at that rate the A/D becomes quite
expensive, and an input attenuator looks forbidding, But there are neat
examples of using the PC for display and control.
Peter Alfke, from home.

Re: FPGA Journal Article
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Digits of precision & granularity ?

But this also taught me that, for top-notch
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A tad outside the average hobbiest resource pool ?

We built a few hundred of the first generation
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Yes, scopes are dominated by things other than the FPGA, so are not
ideal demo-examples.

My favourites would be for Xilinx to do a split
a) Freq Ctr & Signal Generator - Smallest/Cheapest FPGA version

b) Freq Ctr & Signal Generator - Money-no-object version

FreqCtr's can become quite complex - so a series of designs would show
users more and more, but still have a HW platform that is
i)  FPGA dominated
ii) Clearly ahead of any uC alternative


Re: FPGA Journal Article
Jim, beware, you are hitting a hot-button !
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10 decimal digits fixed-point display, but 2 ppm accuracy.
Above 1 MHz limited by time base accuracy, below 1 MHz by display
(just because we are too lazy to make the display floating point...)
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I think so.
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Yes and no. For low-performance, most complexity would be in FPGA,
DRAM, and PC.
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Wait for the S3Eeval board. It includes a freq.gen design based on my
box. Ken Chapman did the control for both of them (PicoBlaze-based), so
you can be convinced it is good.
But it only goes to 80 MHz (?) and the jitter may be more than 100 ps,
since he has no PLL to clean it up further.
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I am going for 2.5 GHz square wave, 1 Hz resolution, and lowest jitter.
But no arbitrary function, adjustable amplitude or duty cycle. All
those things are possible, but clutter up the design. Maybe there will
also come a USB-controlled derivative that offers more freedom.

Please tell me what people need a frequency counter for. I have thought
of a design for years, including reciprocal counting at low frequency
for high resolution with short capture time. But it died for lack of
interest. We could of course include something in the S3E eval board.
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The S3E eval board accuracy will be limited by its 50 ppm xtal, and the
resolution might be pushed to almost 1 GHz. Display is no problem @ 2 x
16 digits.
A 20 times more accurate time base would cost <$20 extra.
I warned you, this is a hot button with me.
My thesis project, looong ago, was a frequency counter. It's deep in my

Re: FPGA Journal Article
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Those do sound like the Smallest/Cheapest and 'other end' I was
talking about.
Why stop at 1Hz ?

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When I say 'Freq Ctr' that is short hand for the higher end Freq Ctrs.
The better ones ( we use a venerable PM6672 here... ) can do
much besides simple frequency.

I'd start with the simplest gated counter designs, and then work up
to Reciprocal and Time-Interval counters, ..maybe Phase too.

A small nudge, and you can make a SigmaDelta ADC display section,
as that's really a % counter.

One idea I have, is for a Dual Readout Recip Counter :
A fast update readout, where the precision is the normal trade
off of update speed.
The second would accumulate precision, so the longer the probe
is held there, the more digits you get.

That gets a little tricky, as the whole system has to never drop
any edges.

Uses: As a software development tool, to verify correct settings.
Common errors are the off-by-one in divisiors etc.

Mostly 2 channel Time-interval, but also frequency.

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That's fine. It should NOT be limited by the FPGA.
Users would be happy to add timebases as needed - yes, even to
atomic ones :)

For higher end examples, how about calibrate/correct via GPS timebase
(still using the low cost xtal)

That expands further, to give an absolute time reference - wider
audience, and with 2 lines, one could show 'human' time, and the other
the snapshot of the 1 sec time pulse from the GPS, probably to
better than 5ns.

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Talking of looong ago, I think my first film-processed project was a
compact 8 digit Freq Ctr, with many old fairchild part numbers.
That was before rubylith....


Re: FPGA Journal Article

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It is easy to go to mHz, just make the accumulator longer, but why?
With 1 ppm absolute accuracy, even the Hz is dubious above 1 MHz.
Who is interested in frequencies below 1 MHz? That also goes for the

Jim, you seem to overestimate the time and energy we here can expend on
sophisticated and increasingly specialized appliations. That's why I
stay with a basic, but extreme design that gives us some real
usefulness and also some bragging rights.

There are always more urgent projects breathing down our necks:
Verifying, testing, finding problems and work-arounds, write
documentation, plan the next generation, prove SEU hardness, deal with
unhappy postings on the newsgroup, give seminars, attend conferences,
analyze the features and find the shortcomings of the "other guy",
support Markeing, but prevent them from exaggerating...
Life is never dull, often challenging, and rarely really frustrating.
Peter Alfke

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Re: FPGA Journal Article

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I showed my homebrew club how to reball and attach Xilinx BG560's
here in my wifes digital convection oven well over a year ago. It takes
a small amount of practice, which gets manageable when you also are
willing to bake and reball. There are lots of trash FPGA's to be had on
boards for a few dollars, and Solderquik preforms make reballing easy.

KISS projects can frequently be pulled off with double sided boards,
are cheap from a number of sources. If doing BGA, they need to be
mask over bare copper (SMOBC) to prevent the balls from wicking under
the mask.

There should not be ANY expensive home project from a parts
as recycling motherboards, industrial boards, disk drives, graphics
etc are a wealth of nearly zero cost parts. Design with what you can
and that is a lot.

I strongly suggest forming a home brew club locally, or even across the
net, and pooling designs onto a PCB panel ... especially when 4, 6, and
layer projects are needed. Most of the budget pcb shops refused
designs, but you can lower your individual costs by sharing NRE's and
setup charges across 3-10 project boards on the same panel. Just be
that you can cut them apart :)

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I'm pretty sure there are a LOT more than just a few of us. I made
in high school (1967) with masking tape for resist, and stoped making
at home when the pcb program showed up for my MacIntosh 128 from
Electronics. I even stopped wirewrapping about that time because it was
quicker and easier to turn one PCB with data paths and most control
in place, and finish the design with point to point wiring and PAL's.

My first BIG hobby project was a Z80 based 9-track tape formatter for
the TMS100
tape drive I had on my LSI11/23 Unix home computer, which I had to go
buy a TRS-80
to write the firmware for.

My current home computer project is a couple thousand FPGA home super
which I've been working toward for a couple years now, mostly because I
like big fast
computers, it's one hell of a challenge, and I needed retraining in
building state of the
art computer systems after being a Unix systems programmer for too many

I do knock off flat fee contract hardware and software designs from
time to time, and
I'm also currently looking for projects. I will also be turning some of
the smaller spare
fpga's from my home computer project into low cost student boards -
using environmentally
friendly recycled parts.


Re: FPGA Journal Article

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I should probably add that Steve's Icarus Verilog (IV) solves that
problem in the
low cost open source tools department.  And it works well targeting
good sized XC4K's and Spartan chips which are easy to design with since
they only require a 3.3V supply. Pick off an older Seagate drive, and
will have a dual 1a linear regulator, 2MB SDRAM, EEPROM with boot
sector, cap's, and a few other parts to build an interesting robot
stomp box effects processor, home controller, or other project with a
recycled wall wart.

And FpgaC for open source reconfigurable computing (read executing C
code as circuits) is getting off the ground to do the same for C coders
not interested in learning VHDL/Verilog as their only way to program

You will find both FpgaC and IV on sourceforge.

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