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Everything posted by jpnorair

  1. Cool. The stock Chronos 433 antenna is absolute rubbish, though, so it is a low bar. In any case, I can mail you a hand-built ~5cm reference monopole, if you want to compare RSSI readings (send me a PM). I have tons of these, which I manufacture in the lab. Normally I don't offer this sort of thing, but you are actually working on something that is of interest to me. The same offer goes towards anyone doing 433 MHz Chronos work, or for that matter CC430, CC11xx, and CC1200 work. It's also important to mention that a single-ended antenna (monopole) needs a decent-sized ground plane
  2. How did you design this antenna? Using a helical winding is a difficult way to build an antenna. You need to determine the impedance and make sure that it is the proper terminating impedance, which is largely an experimental process. Generally speaking, however, the total uncoiled length of an inductively loaded wire antenna is quite a bit longer than the equivalent straight-wire antenna.
  3. The obvious answer is that the advantages of using OS X outweigh the downsides, at least for me and many others.
  4. I do a lot in a VM, but VM is clunky and slow during compiling.
  5. Bold words for a guy from Redmond Washington! Well, I went to school in New Jersey, and they had swapped-out their Sparcs for Macs in 2002, so it's not just Silicon Valley. In any case, the big conferences here draw people from all over. It is becoming strangely unusual to see Windows laptops at these conferences. I think I even met some TI-ers at a San Jose embedded show who were using Apple laptops.
  6. My observation when attending industry shows and conferences.
  7. It's a shame it doesn't support OS X. You think TI would have figured-out that in the last 5 years, virtually all software devs in the USA have switched to Mac, and this represents a lot of the hobbyist community. I use a mac for my personal laptop, and if CCS were available to run natively I might muck around with MSP430 on the weekends. Oh well, maybe v6.1.
  8. Duvel is not a microbrew. It is from Belgium. It is pretty much what everyone is trying to copy with the spicy ales these days. Duvel is cool about this: a few years they made a Duvel Green that sort-of copies new American ales. It's great, too. Guiness may be Irish, not English, but it is of a style more common in England/UK than anywhere else. There are some great English ales. If you find a good English pub (most US cities have some), you can sometimes find some ales using the old-style taps. Guinness has used technology to supplant the old-style tap, and then more technology to
  9. I have not had this, but based on what I can see on beeradvocate, you might enjoy Duvel Red as a weekend beverage. There are many other US microbrews of similar style (some much better, some much worse), but they might be difficult to get. Make sure to pour in a glass! Alternatively, have you tried any English ales? Some of these, you can buy in cans with the Nitrogen widget. The last beer I had was on Saturday. It was a bottle of one of the newer Sam Adams varieties that is trying to ride the IPA thing. I'm not a fan of IPA, but there are many superior examples. My easy-to-obtai
  10. TI releases PDFs of the copper layers for most of their dev kits. You can find these documents on the TI webpages for each dev kit in question. You can probably figure out how to overlay these images in an image program and search for open spaces. Also, it most cases you aren't going to hurt anything by drilling through a ground plane or ground pour.
  11. Here is an overview. http://rampac.energy.gov/docs/rfid/RFID-INMM09.pdf Edit: Here is an article specifically describing the irradiation process. (see page 42) http://rampac.energy.gov/docs/rfid/Paper1.pdf
  12. Yes, although the parts in question were 1-series MSP430s. The MSP430 was part of a radio tag that was being mounted onto canisters of Plutonium and Uranium recovered from Eastern-Bloc nuclear weapons and submarines. The project was from the Department of Energy, managed by Argonne National Lab. If I remember correctly, the expected mean-time of failure was 17 years, given typical conditions for that application. I know this, because I was one of the guys who sold DoE/ANL on the tag platform. The ANL team was great, and they published a lot of their work.
  13. I realize that, but most of the high points in engineering seem to happen this way -- insane dedication by a small number of engineers (or just one). It is proven and time-honored. [insert trendy model here] is not.
  14. That's a bad assumption. If there's a market, someone will do it. There are plenty of non-Java languages that could have filled the role(s). I'm not knocking Java here, so much, simply as being pedantic about the assumption that for some reason the internet benefitted uniquely from any programming language in particular. I found this post from 1982 that I thought was funny (http://www.multicians.org/thvv/realprogs.html). In my opinion, a good software team is one that has plenty of "real-man" programmers, although I don't care as much about the macho thing as I do about willingnes
  15. This is a common argument for all kinds of stupid things. It doesn't make them less stupid. The problem starts with the spec and the concept itself. Since that is flawed, the rest has no hope.
  16. IMO, Java is badly written software. <arnold>Stop being a girlie man and learn C.</arnold> For embedded, it makes sense. It also makes sense simply for being a better CS student.
  17. The interrupt that gets blocked will be serviced after the first interrupt ISR returns. Just to say: it is also possible to use a TIMER peripheral to do multichannel PWM, but maybe that is a project for the future.
  18. I am going to warn you, I am an optimization freak. I have heard some stories about engineers using my code and going crazy, so it a good thing this one is only 2 lines. For keeping interrupts short, when the ISR is tiny (millis++) or almost tiny (your original code) there is no practical difference in terms of multitasking. The entry time and the RETI (return from interrupt) will take more time than the ISR code itself in both these cases, unless you are running at extremely low clock frequency. Also, sometimes it can be OK to have long interrupts. It is a problem only when there is
  19. Is flipflop supposed to divide by 2? It is a variable declared on the stack, so unless there is some hack or feature of WDT interrupt I don't know about, it is not going to work the way you want. Easier way to divide by 2 is to just have millis++ in the interrupt (nothing more) and then have get_millis() { return (millis >> 1); } or something like that.
  20. 5529 launchpad indeed works to program CC430 over SBW. So does the Chronos dongle (naturally). Make sure to set-up CSS with HW breakpoint only. In any case, if you're doing any kind of real time networking, HW breakpoints are all you want to use anyway. Olimex makes a direct replacement for the 430FET which is much faster. Sometimes, that's worth the money.
  21. Nice, although I'm a bit surprised they didn't use an SoC of some sort -- using BT kind-of negates the idea that energy efficiency was a central design goal. In any case, I have a friend at Lab126... I will ask if he was involved.
  22. Since most if not all MSP timers can be driven by ACLK, you actually have a lot of low power timers you can use, independent of the master or submaster clocks. This is one thing that is really, really great about MSP430. Just get a 32kHz crystal instead of 32768, although using 1/1024 second is usually OK.
  23. In the lab we use a Dark Horizons (3rd edition) can as an attenuator for HayTags. That was a very sweet and strong beer. I know beer is expensive in Norway. If I lived there I would definitely brew my own. Making strong beers like IPA is actually not too difficult. Soft, smooth lagers are almost impossible. Maybe there is a project in this: launchpad controlled brewing equipment...
  24. That is why there is Belgian beer. Blanche de Bruxelles is especially popular with non-beer-drinkers (yes, I'm talking about young girls, but at a certain age you don't care about that sort of thing).
  25. I had a marathon day on Thursday that extended into Friday, doing engineering work of course. Now, I have a 6-pack of Trumer Pils with my name on it. Yes, indeed it is there (I added it with a sharpie).
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