Generally, to deal with the port you need to know the DDR register, PORT register, maybe the PIN register. I am wondering if there is an easy way to get one from the other.
It seems like in the memory map it is PORT_<<DDR_<<PIN_, but I am worried about relying on this
Is there some AVR libc function for doing this kind of register/port "math"?
@coding_corgi Don't know how to program an AVR that has a bootloader already on it. The compiler needs to be aware of this fact as the used memory addresses will need to be different.
@angelatlarge Also, from a design perspective, a derivation is not feasible because we're talking of separate "degrees of freedom", so to speak. What is possible, and I've seen it done in some platforms, is entire arrays of #defined named bitstreams such that the first N bits are the device code, the next few are the port, and the last few are the bit-position in the port, for a specific function.
That chap who wants to use the iPhone to control an external device, amuses me. He's got an expensive iPhone, and yet he wants to make a prototype wireless control add-on for less than $5 for a one-off!
@angelatlarge That's why I amended my comment to ask that.
At less than $5 for a one-off, there don't seem to be any evident options. At best, an IR LED might be worth exploring, if it can be driven from the audio jack - extremely unlikely that the headphone port can support the currents needed by an IR LED, though. Just out of curiosity, how much did the iPhone cost, in contrast to the prototyping budget of $5? — Anindo Ghosh4 mins ago
@jippie Yup, I've chastised team members for that misuse on occasion, too.
@jippie Don't forget the misuse of the word "only", often as a sentence terminator.
@jippie Another one: "Going to native", that too often pronounced "going to natiUe", which is supposed to mean visiting one's place of birth, and not "going native" or declaring the workplace nudist-friendly.
@AnindoGhosh I have about ten colleagues in Utrecht which I all know personally, the rest of my colleagues are all in India, so I can safely state that only my Indian colleages use the word ;o)
@tigrou PWM is a square wave, only the duty cycle differs. What is your PWM's highest voltage? Does this voltage go beyond your device's absolute maximum input voltage rating?
@tigrou PWM itself is not inherently harmful to an IC. The IC, whichever it is, will typically have a maximum voltage rating. So long as the high part of the PWM signal does not exceed that, the IC will not be harmed.
@abdullahkahraman Oh well... My hunt continues. I have a nice Inventor model for the SMD version of the PC817 optocoupler, and I need to get it to 3ds format, so I can import it into Proteus 3d Visualizer
@AnindoGhosh, I haven't used it for a while but TurboCAD supports a fair few formats and can export 3ds, I think inventor can export to a few formats on this list like DWG can't it? I think it has a 30-day demo.
@AnindoGhosh, I'll try a few more things, but it didn't like that for some reason. I have v18 of TurboCAD although it's only a year or two old and looks like it should support both.
@AnindoGhosh, TurboCAD just said "couldn't open" or similar, but DWG TrueView 2011 says the version is too new so maybe the file formats have changed in the past few years. I can't see an IPT import option in TurboCAD, I don't support you get an option to save an older version of DWG?
@AnindoGhosh, I can load those versions OK but a 3ds export gave a warning that some features are not supported and just creates a 42 byte file, presumably just the header :/
@AnindoGhosh, just checking and in DWG TrueView it looks good and what I'd expect, it seems TurboCAD won't import it properly let alone export so can't help.
@vvavepacket it was good, but nowhere near focused enough to really be considered 'graduate' school. it was basically another year of undergrad but i was only allowed to take 400+ courses
i didnt have to do a thesis or anything, just 10 400+ courses
@rawbrawb yeah, well i had 2 carry over from my undergrad years that i didnt need to graduate so in my grad year i only had to do 4 per semester. which was still a lot of work, but i managed to get a 3.5 GPA and learn a good amount so i was pleased
@vvavepacket Micro Electro Mechanical - machines might be over stating it because people think gears and motors. the stuff I work on is more like cantilevered beams, so parts move but they don't spin.
@vvavepacket in my application I can't tell you, but this could easily be part of a process for rate gyro's , accelerometers, silicon photonics (as a waveguide/light pipe) etc.
@CamilStaps Currently I am trying to figure AVR programming out, I am starting to get VERY interested in ARM and I am trying to disassemble a wireless router! Yeah! Networking!!!
@rawbrawb By now, you of all people probably know that I have a near eidetic memory. What none of you know, perhaps, is that I also have a totally hopeless memory when it comes to names (people, places). It's like a scary black hole in my memory - I can forget a name less than 5 minutes after I myself mention it.
By the way, this question is begging for a nice pedantic answer describing bias current null, offset null, the legacy op-amps and their offset null pins, and suchlike. If it wasn't this late at night, I might have ventured to do something along those lines.
I'm using an industrial amplifier which has coarse and fine balancing. I uploaded the circuit picture and circled the fine balancing in red. I use it to zero the output(for offset). It is done by turning it by a screw driver. I just wonder if it is a potentiometer or a capacitor. Any idea how it ...
@rawbrawb Well, I've got that one sorted. Courtesy a certain period in my life, and one of my various parallel careers, I have a condition called tinnitus. This permits me to blissfully ignore anything the wife says from another room. When confronted, my standard response is "If you can't come here to speak, send me a text message!"
By the way, now that there are a few people on chat who were not, earlier, I'll restate a question I had earlier - Does anyone use 3ds Max, or have any means to convert an Autodesk Inventor .ipt file into a .3ds file? If the file could be optimized to reduce the number of polygons at the same time, even more useful.
actually, so does this question. poorly worded but there is a chance there. I'm about to head out though. Would be nice to get those cleaned up before the snarkies appear.
I have been seeing these switched capacitor circuits for some time now and have even seen Z-transform being used to model how these circuits behave. While I can see that there is some capacitor that switches, what exactly is the mystery behind this 3 terminal device one terminal of which comes fr...
@rawbrawb Yeah, I noticed that one as well, but it's not of as wide interest to a newbie electronics experimenter, I felt, so I picked the other one for redemption. I did vote up the capacitor question to counter the flyby down-vote, though.
@rawbrawb Nice... Won't read now, but might suggest edits if I have any bright ideas on the morrow.
@vvavepacket My specialization is non-specialization. I work in a range of fields, not just EE and EE-empowered ones either. :-) Multi-discipline engineers are not common, though.
@rawbrawb I remember a company that used a mirror held on a MEMS cantilever beam to tune a laser --- searching on the name it doesn't look like they lasted very long.
@jippie I am getting REALLY obsessed with ARM and Raspberry Pi! I am going to try to stay on AVR for a couple of more months! Let's hope...
@jippie But there is a hidden supply of Raspberry Pis at a computer store, nobody but me goes to the electronic section (probably) I am sure that those Raspberry Pis will never be bought, except by me...
@jippie I got a stupid little ATmega328P-PU from a kit, and it has like the pinout on a sticker on top of the AVR. But it said Arduino Bootloader Preloaded, or something like that, so does every AVR on an Arduino have the bootloader on it?
@ThePhoton Well there is the TI DMD - for projectors (that is an array. and the GLV - grating light valve, fabbed at cypress from silicon light. But given your area of work you're probably thinking of a tunable cavity laser, I'd love to hear more about it.
Eyes hurt from working w/ 0805's all PM. I'm a wimp. Just thinking about when I made the change from IC's with only SMD packages being a PITA to components with through hole packages becoming the PITA.
@rawbrawb I use it for whatever kind of numerical stuff I have to do (unless I need the statistics stuff from R) --- but I've never used Matlab so I can't compare how much better/worse it is.
@rawbrawb The company I'm thinking of was Bandwidth9. They had a tunable VCSEL, where the top mirror was stuck out on a cantilever, and you tuned the wavelength by moving the cantilever up and down with a electrostatic force. Beyond that, I don't remember much about them.
@ScottSeidman You're just over 35 -- aging is not for wimps.
@ThePhoton Just over 45! But I'll take the decade if you're handing them out!
Hands are getting a bit jumpy, too. I think my familial tremor might be starting to kick in. I'll have to do a field lab tonight to make sure its not Parkinsonian. If a few beers quiet the tremor, it's not Parkinsons
@ScottSeidman Haha, I was going to say higher, but I wanted to use a cut-off that would include me --- I sure can't hand-solder smt like I could 5 years ago.
@ScottSeidman Even in grad school I had to skip coffee if I wanted to do fine work (manual wirebonding) that day.
@ThePhoton I drink about a quart thermos of coffee every day. Maybe I should hold myself to one cup before taking on a board.
I just love this board, too. Isolated patient lead area, so you can run a finger around a nice rectangle, and not cross any traces. Not strictly necessary, but I really want to go through clinical engineering only once, then take it to a review board to get a locally issued investigational device exemption, instead of having to take it to the FDA.
@ThePhoton I've used Matlab, Mathematica and various others but my favourite is actually Mathcad, mainly because you can get almost publication quality material and plots all in one document. Do you find you need many plugins and 3rd party tools? because Matlab has those in spades, image processing wavelets, FEM etc. very useful.
I'm thinking of getting a OSS flow going, I'm not sure is I should go for SciPy or Octave or ....
@ThePhoton bandwdth9 - thanks! I don't work in the emitter side so I don't knkow these guys. Very interesting.
@rawbrawb I've been pretty happy w/ Octave. I go to it more and more even though I have Matlab, as when I VPN into another network to authenticate, I get booted off of my local net for some odd reason.
2. What SciLab has going for it compared to Octave is a Windows port that runs without hassles.
3. I'd consider SciPy but am not in the mood to learn Python.
4. I don't use a lot of plug-ins. FFT's are pretty much the most I need to do in terms of fancy processing. But there are a lot available... just check the website.
The one thing I would get more fancy with is statistics --- but for that I use R.
@ThePhoton Good point. I gave up on Windows ports by running VM's. I find myself spending more and more time in Linux these days. It's much less aggravating than when I tried to run it a decade ago.
Yeah, in reality neither is Mathcad, but it looks a look better than Matlab array indices etc. Octave looks interesting but it's a little more "glued together" , there are some tools I've been thinking of developing and python is looking like a better choice daily, especially with the OpenCL - and GPGPU plugins.
Also R has a package called "ggplot2" that produces some nice output --- but R has so many quirks as a language I wouldn't recommend it to someone who doesn't have a compelling need for R's strong areas.
@rawbrawb Many of the folks around here who do stats for a living seem to be using R. I like it enough, but learning all the different available graphics addons is confusing.
I switch to open source stuff whenever I can, just because when students see me using something productively, they tend to pirate it, and it makes me feel guilty.
@ScottSeidman What I find annoying is figuring out all the different ways to store data: vectors, data frames, matrices, lists, ... and different rules for when you can and can't use each one, and how to index them...PITA.
@ScottSeidman interesting ... although I tend to rip out OpenOffice/LibreOffice in every distribution just because it just isn't quite compatible with MS -office and everyone uses that.
@rawbrawb It's an example from their docs. I think it's a "loess" fit (spline fit, more or less) with 95% confidence intervals. Obviously the data doesn't give much to work with when fitting.
well scilab looks interesting enough that I think I'll down load it. I've been modelling in excel just because I can't make up my mind, that should be a warning sign that I need to commit! or be committed.
@ScottSeidman technically based and reasoned excuses for drinking are always welcome! thanks!
@ThePhoton I'm only 5 rep points behind @W5VO right now. what with TS slaging him on posts and idiots like me passing him he'll need even more support.
@JohanLarsson I tend to do mathematical modelling and not control systems , but then I may not understand what xcos is ... just looking at basic functionality.
@ThePhoton It's gotta have mounting rules ... like "use XXX oz cu plating and YYY square inches ..." or something similar . Otherwise it's counting on solder reflow to act as a fusible link.
@ThePhoton you know, this sparks an idea, I've been wondering how best to build a test pattern generator for thermal imagers ... This might be the way.
@rawbrawb Thinking about it, and the applications they mention, I suspect a lot of their customers are not mounting them on FR4...They're probably going on ceramic substrates.
@ThePhoton yeah, that makes sense. And also why you might have been pinged given that some of your RF stuff is probably the same. Or the modules are.
@ThePhoton this is one of the reasons why hanging on chat is handy though ... I'd not have heard of that otherwise, so it may have solved a problem for me ...
@rawbrawb We mostly work at the (relatively) low cost end of optical communications...our customers won't pay for stuff like that. Maybe in a 100 Gb/s DWDM product you could afford it, but not on the stuff we make.
