EEVblog #494 - Mailbag

[EEVblog]

USB Serial Module: http://jim.sh/ftx/
DSRB-88 Geiger Counter:
Induction Coin Shinker: http://thegeekgroup.org/stomper
FPGA Development Board: http://de0-nano.terasic.com

[ChrisBoden]

Thank you Dave!

[c4757p]

I love how symmetrically shrunken the quarter is - the text and image aren't distorted at all! It's impressive that you can shrink something like that to two thirds its diameter in microseconds and do it so perfectly.

[ddavidebor]

For the geiger counter try  with a clock with luminescent background, the one that you can see in the dark.

[nitro2k01]

You probably have to lift the skirt off of the smoke detector to get a signal. It's just an alpha source, and probably covered with a metal can to keep the radiation out. Please weigh the quarters. My prediction would be that the compressed one is slightly heavier due to oxidation on the surface. And FPGA videos, yes please!

[electronic_eel]

Yes, please do some FPGA videos. I have just experience with microcontrollers yet and think reconfigurable logic is an interesting topic to learn something about.

[dentaku]

Well, that made a decent dent in your mountain of mail.

[ddavidebor]

But still a bit disappointed by this mailbag. A lot of (nice) postcard but only 2 nice items

[c4757p]

Please weigh the quarters. My prediction would be that the compressed one is slightly heavier due to oxidation on the surface.

Can two randomly selected, clean quarters be expected to have such similar mass that a bit of oxidation will make a measurable difference beyond the existing difference between them?

[Winston]

I definitely want to see FPGA segments using the DE0-Nano, please.  I've always wanted to know more about FPGAs.

The Timberline Lodge you looked at in the Oregon calendar was used in the classic Stanley Kubrick film, "The Shining" which was a rare example of a movie that was far better than the novel it was based upon, thanks to Kubrick's great talent, of course.  From Wikipedia:

"The 1980 movie The Shining used aerial shots of the Timberline Lodge as part of its opening scene, and exterior footage for some establishing shots of the fictional Overlook Hotel throughout the movie. The movie was based on the Stephen King novel of the same name, which was inspired by The Stanley Hotel in Colorado.[citation needed] Several of the exterior shots in the film which purport to show the lodge, such as those of the hedge maze and loading dock, were taken at Elstree Studios in England, using a mock-up of the south face of the lodge. There is no hedge maze (and hardly any level ground) at the Timberline Lodge. All interior scenes were shot at Elstree Studios as well, and do not depict the interior of the Timberline Lodge."

[TheWelly888]

Another vote for showing us the FPGA demo! It's a new area for me.

[nitro2k01]

Please weigh the quarters. My prediction would be that the compressed one is slightly heavier due to oxidation on the surface.

Can two randomly selected, clean quarters be expected to have such similar mass that a bit of oxidation will make a measurable difference beyond the existing difference between them?

If I knew, I wouldn't be asking. Then again, the question is if Dave has a precise enough scale.

[c4757p]

That's probably about as likely as a chemist having a 6.5 digit multimeter.

[SeanB]

I have the massmeters but not the crusher........

[daqq]

Hi Dave,

If you're looking for an accessible rad source, try thorium wolfram welding rods. It's not particularly radioactive, but certainly it's above the background.

On the topic of your smoke detector - those are mostly made (or were) with americium 241 - an alpha emitter, which was enclosed in an ionization chamber - it would certainly not emit outside of the detector. Even if you were to open up its guts, the geiger counter might not be able to pick up the alpha particles.

David

[synapsis]

Another thumbs up for FPGAs. 

I've had a DE0-Nano sitting on my desk for over a month and it's quite a bit to get your head around for "young players." I have experience in industrial PLCs and desktop multithreading, but I still need to adapt my thinking to concurrent execution.

And you're not missing too much down here in Southern Arizona. We have the San Xavier Mission and the border "fence", with the occasional ghost town here and there. If you do get down here, I believe you'd really enjoy the Titan Missile Museum. It's interesting to see the 20+ year old control systems.

[Winston]

The Geek Group's quarter shrinking "stomper":

Project Stomper Mark 4 Walkthrough (CGI)



Early Stomper Tests (Crude Prototype)

[Winston]

And you're not missing too much down here in Southern Arizona.

Don't forget the Kitt Peak National Observatory telescope complex!

http://www.noao.edu/kpno/

I was a visitor there long before the post-9/11 paranoia, so I don't know how things are done now, but I just walked around and into the various observatories which had plexiglass-enclosed public viewing areas within the domes.  Awesome hardware!  I was wearing a T-Shirt which said "Life's a Mountain, not a Beach" countering the popular T-shirt then which said "Life's a Beach" (after "life's a b*tch and then you die").  I was there during a weekday and was alone except for an older couple who were walking around like me who assumed I worked there, probably due to my relative youth and my T-shirt.

Of course, Meteor Crater and the Grand Canyon are absolute must-sees in northern AZ.  Petrified Forest National Park is fairly interesting, too, along with some ancient native American structures and a smallish volcano ash dome (can't recall the names of either).  And, Dave, I don't know if it was just my viewing point, but on my second visit to the Grand Canyon I went to the northern side, more out of the way and not worth it in my opinion if you've already seen it from the southern side.

[free_electron]

I watched some video's of Thegeekgroup thinking, cool , another hackerspace. but all i see is a bunch of rednecks having some fun of the type : hold my beer and watch this...

I don't get it. Its supposed to be a hackerspace ... Very little hacking going on. All they do is yell out high voltages and then destroy coins .

I don't get the obsession that people have with that stuff. It is dangerous , and useless.

[synapsis]

And you're not missing too much down here in Southern Arizona.

Don't forget the Kitt Peak National Observatory telescope complex!

http://www.noao.edu/kpno/

Very true. I grew up near the base of Kitt Peak (yes, middle of the desert nowhere) and totally forgot about it. Last time I was up there was 1986.

[c4757p]

I don't get the obsession that people have with that stuff. It is dangerous , and useless.

It's a challenge to build things and fun to watch what you built do something "big". Building something that can crush a coin like that isn't trivial (OK, it's not quite building an oscilloscope, either) and it's exciting to see your project do something you couldn't do yourself.

People like "hold my beer" entertainment for a reason.

[Winston]

All they do is yell out high voltages and then destroy coins .

I don't get the obsession that people have with that stuff. It is dangerous , and useless.

Personally, I just like concept of the tremendous symmetrical force of the EM field and counter-field produce by 100,000 amps flowing through a heavy gauge copper coil that vaporizes into a plasma while inducing as much as 1,000,000 amps within the quarter.  Very cool. P.S. - I'm similarly fascinated with thermonuclear weapons.

Back in the early 2000's when silver was much cheaper, I asked this guy if he could shrink a 1 oz, pure silver Silver Eagle:

http://www.capturedlightning.com/frames/interesting1.html

Back then, I believe he may have had a different, lower energy system, so he said to send him a Silver Eagle, he'd give it a go, see if it worked, then send my shrunken coin (or debris) back at no cost to me.  What a deal!  It worked and he used my coin for his shrunk Silver Eagle photo (back then anyway; don't know if he still does and I don't have my coin handy to check which reminds me that I need to find where the heck I put it!)

Semi-technical paper on his system:

http://www.capturedlightning.com/photos/shrinker5.pdf

[FrankBuss]

The DE0 nano board is nice, I have it too. In combination with NIOS you can write C programs with it and access (memory mapped) blocks implemented in VHDL (or Verilog). When I tested it, it was a bit difficult to integrate the SDRAM in NIOS, needed a PLL instance in Quartus to work, with the right phase shift etc., but then you have a good 32 bit soft core CPU and lots of RAM, and IPs on the FPGA to use. And with the Eclipse based IDE you can even single-step debug your programs.

For VGA maybe take a look at my YaGraphCon project: http://www.frank-buss.de/yagraphcon/ . The bit depth is a generic parameter, but only BRAM support so far, but easy to use if you just want to display something like text on a VGA display (sometimes you can even get them for free in the dumpster ). Recently I changed it to a register based interface instead of the SPI interface, which works already with a 6502 soft core, which is inside a port of an Atari 2600 implementation I work on for the Turbo Chameleon for an OSD:

https://github.com/FrankBuss/TCA2601/blob/master/YaGraphCon/YaGraphCon.vhd

Should be easy to integrate as a component in NIOS, but I guess there are VGA controllers in the Quartus MegaWizard as well, but I can't find it. Anyway, always more interesting to write your own entity than using some IP block.

[99tito99]

Hi Dave:  Yes, maybe a multi-part blog on FPGAs and Nano FPGA Development Board(s).  Part 1 for the Newbies (me included) would be brief intro to FPGAs, the basics, how they work, different types, etc.  And then certainly several demo project including how to do the basic programming.  Cheers, Science-Mark

[Sine]

That radiation detector is a VERY crude one, the detecting tube looks like a MTX-90 cold cathode trigger tube that is used for absolutely everything ( including light switches apparently ) in Russia.

[EEVblog]

Please weigh the quarters. My prediction would be that the compressed one is slightly heavier due to oxidation on the surface.

I think that would be pretty pointless unless you knew the mass of the shrunken coin to begin with.
I doubt the usual mass variation in two (used?) coins would be substantially lower than any measurable oxide layer.

[dexters_lab]

nice to see the counter arrived ok, the sbm10 tube is actually at the other end of the pcb under the wax, the mtx90 is i think just a light

[LoyalServant]

Another  for FPGAs...

It's something that I have been meaning to dabble in myself.

[crisr]

I too would love some segments about FPGAs! Like what kinds of applications they are best suited for or what can be simpler / faster / better with them, and also how VHDL / Verilog work...

About the quarter, it either got some mass vaporized or it is thicker,  I don't think the magnetic field could change the density of the metal.

[CodyShaw]

I have the DE0-Nano, it's a great board.

See a little sample of something I made here:

http://codyshaw.ca/2012/06/02/8-bit-adder-update/

I really need to update my website...

[ukee1593]

I would love to see some FPGA based tutorial videos Dave!!  I might have to get one of those development boards so I can play along at home

[skylersaleh]

I would very much like to see some FPGA videos.

I actually own the exact same board, and have rather enjoined using it.

[FrankBuss]

See a little sample of something I made here:

http://codyshaw.ca/2012/06/02/8-bit-adder-update/

Nice. I don't know much Verilog, can you do loops with it to avoid instantiating every single one bit adder by hand? Would be worse for a 32 bit adder.

Here is a 4 bit multiplier I created when I learned VHDL:

http://tinyurl.com/odkh58p

See the "generate" loops, which would make it easy to implement a 32 bit multiplier without more code (but very many gates, because it is all static and parallel).

[mrflibble]

Nice. I don't know much Verilog, can you do loops with it to avoid instantiating every single one bit adder by hand? Would be worse for a 32 bit adder.

Yup, verilog has a generate block that works pretty much the same way.

[TheWelly888]

One question I have about FPGAs: What is the difference between microcontroller/processor based digital systems and FPGA based systems?

[Rigby]

Dave, you said to let you know if we were keen on seeing a video where you generate video from GPIO (as my admittedly faulty memory is telling me, anyway) and I'd love it if you could show how to drive a 15kHz arcade monitor with GPIO, or something like it.

[ptricks]

I have some of the microFTX usb-serial and like them a lot.  The price is right and because they are so small it makes it possible to easily add them to things that have internal serial connections like routers, media player set top boxes, so that I don't have to wire up a serial port any time I want to access them, just connect a USB cable.

[gardner]

show how to drive a 15kHz arcade monitor with GPIO, or something like it.

There is a widely used library for Arduino that bit-bashes B&W NTSC or PAL video using two pins and some resistors.
The AVR ATMega is fast enough, but there is so little memory on the typical Arduinos that managing a frame buffer is pretty challenging.

http://playground.arduino.cc/Main/TVout

[carbon dude oxide]

I would definatly like to see some fpga videos, i have never used them or understood what they were so it would be very helpfull

[ThomasChr]

@TheWelly888:
FPGAs are some kind of programmable Logic.
Think of them as Millions of Transistors which can be connected in any kind of way by a programming language (Verilog or VHDL).

A FPGA Chip can make some simple AND, OR, NOT or it can be a whole Atmel Processor, or even an Intel Processor.
You tell it what it is :-)

Thomas

[jucole]

I would definatly like to see some fpga videos, i have never used them or understood what they were so it would be very helpfull

You're in for a treat!  when the penny finally dropped for me I couldn't sleep properly for a whole week! ;-)

[tridentsx]

I want to see some projects with the fpga

[c4757p]

Think of them as Millions of Transistors which can be connected in any kind of way by a programming language (Verilog or VHDL).

Logic gates, not transistors! You're not going to get a long-tailed pair! Though I suppose you could build a CPU and stick SPICE on it...

[iva]

That's probably about as likely as a chemist having a 6.5 digit multimeter.

Not sure.
I'm into ancient roman silver coins (besides software and hardware!) and I bought a jeweler's scales having a 0.001 g resolution for 70 euro, if you could point me to a 6.5 digits dmm for the same price that would be great 

The cool part is that having that resolution you could measure the specific gravity of a coin helping you determine fake ones or their composition - not that I personally did it but was fascinated by the idea:
http://www.attilacoins.com/Calculate_Specific_Gravidity_coin.asp


Sorry for the OT which is still geeky enough for this forum (!), in any case +1 for the FPGA stuff, I usally play around with Xilinx tools and boards (I like them a lot) and would be great to have something about the competition. 

[mikepa]

One more vote for some FPGA videos

[joab]

Nice! I also have a DE0 NANO. I got it just a short while ago so I haven't done anything with it yet, but my goal is to learn how to use FPGAs using it, together with my DE1 board. I've worked a bit with FPGAs in school, but haven't done much yet. I would love to see some videos where you use the FPGA.

[deephaven]

FPGA videos are a brilliant idea. I'm just wondering if there will be Altera vs Xilinx fights like there are with Microchip vs Atmel 

[nitro2k01]

FPGA videos are a brilliant idea. I'm just wondering if there will be Altera vs Xilinx fights like there are with Microchip vs Atmel 

"Some prefer one, some prefer the other. Both are perfectly good alternatives." Done!

[ptricks]

FPGA videos are a brilliant idea. I'm just wondering if there will be Altera vs Xilinx fights like there are with Microchip vs Atmel 

Nothing to fight about,  everyone knows that Altera is the best !

[ddavidebor]

So, dave, seems like you have a 100% thumbs up for fpga!

[FrankBuss]

The Lattice parts are nice too, e.g. the MachXO2: Powerful as a small Altera Cyclone (PLL, hardware multiplier etc.), but with integrated flash, like for CPLDs, and available down to WLCSP packages (that's 2.5mm^2).

[ptricks]

I was lucky enough to get one of these boards for cheap:
http://www.embeddedarm.com/products/board-detail.php?product=TS-7300

Arm 9, CPLD, FPGA all on the same board with pinouts, sd card slots and more.
You boot off the sdcard into ARM Linux and then just use console commands to load and control the CPLD and FPGA.  Makes development easy, no extra hardware required.You can even connect a keyboard and monitor and use the board to write the code for the FPGA .

[FrankBuss]

I was lucky enough to get one of these boards for cheap:
http://www.embeddedarm.com/products/board-detail.php?product=TS-7300

Looks good. The ARM CPU is a bit slow for todays standards, but a high speed bus between the CPU and the FPGA can be used for many interesting applications. I can't wait to get my Parallela board.

[Corporate666]

Big additional thumbs up for FPGA videos...

I really love Dave's videos, but I have noticed that maybe as the blog has become more popular, there is more teardowns, equipment reviews, mailbag, etc.  And there have been less videos which might appeal to real engineers and designers.  This is not a criticism at all - Dave should do what sells of course   but as for me, I would LOVE to see not only some FPGA videos, but it would be fantastic to see a few episodes about actually making something tangible... not just some example project blinking an LED, but a real project... similar to the Mu Current, or the USB power supply, or the exterior LED patio lighting.  Something we can follow along with and see it being done... I miss those kinds of videos.

[ddavidebor]

the last time the project stuck...

[JoannaK]

This reminds me, I stilll haven't send my packet to Dave. Like year and half gone since I got the idea, well. Perhaps before Xmas.

[SeanB]

No problem, he might open it by the following Christmas........

[carbon dude oxide]

Or the christmas after that

[Crazy Ape]

See a little sample of something I made here:

http://codyshaw.ca/2012/06/02/8-bit-adder-update/

Nice. I don't know much Verilog, can you do loops with it to avoid instantiating every single one bit adder by hand? Would be worse for a 32 bit adder.

Here is a 4 bit multiplier I created when I learned VHDL:

http://tinyurl.com/odkh58p

See the "generate" loops, which would make it easy to implement a 32 bit multiplier without more code (but very many gates, because it is all static and parallel).

I created a 4 bit multiplier in VHDL as well. I'll have to dig up the code.


I was messing around a bit with some small capacity devices from both Xilinx and Altera. I do have a DE0 Nano so I guess I'll have to bust it out of it's box and join the fun. I'm sure I have some interesting code around.