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vinicius.jlantunes

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  1. Like
    vinicius.jlantunes reacted to jpnorair in Mailbag   
    Yeah, I don't guess solar is the most cost effective power generation technology in the UK.  
     
    Maybe you can collect rain and run it through hydro.  
  2. Like
    vinicius.jlantunes reacted to Fred in Mailbag   
    @@jpnorair It would be much cheaper here in the UK... because a full roof solar panel would be perfectly matched with a couple of AA NiCds.
  3. Like
    vinicius.jlantunes reacted to Fred in Mailbag   
    I'm not sure if this quite counts as "mailbag" as it's a bit big, but this was delivered recently. A nice new workshop for the end of the garden that I'm currently busy kitting out with workbenches, power, ethernet, etc. It obviously also required the purchase of some more power tools to do the job.
     

  4. Like
    vinicius.jlantunes got a reaction from bluehash in Mailbag   
    I am so happy I have to share it with the world. Finally got a Dremel! These things are so darn expensive here in Brazil (just like everything else) that it took me a while until I could buy one. Actually I received a gift from my employer which covered almost the entire cost, I only had to put a few bucks on top of it. Can't wait till I get home so I can drill something 
     

     
     
  5. Like
    vinicius.jlantunes got a reaction from RROMANO001 in New MSP-EXP430FR6989 128KB FRAM Launchpad Discounted to $13.99   
    I feel sad now when I see these offers. In the good old days of free shipping I would get one of these no doubt, but now cost of shipping to Brazil (+ import duties) is prohibitive.
  6. Like
    vinicius.jlantunes got a reaction from Fred in New MSP-EXP430FR6989 128KB FRAM Launchpad Discounted to $13.99   
    I feel sad now when I see these offers. In the good old days of free shipping I would get one of these no doubt, but now cost of shipping to Brazil (+ import duties) is prohibitive.
  7. Like
    vinicius.jlantunes reacted to roadrunner84 in "Your Ideas are Worthless"   
    personal time, what's that? oh, that stuff I had before I got kids
  8. Like
    vinicius.jlantunes reacted to austen520 in Self-balancing PID robot w/ code + schematic + UART tool   
    I recently completed a final project for an undergrad circuits class, throughout which this forum was a huge help, and so I just wanted to try and give back a little by presenting our code here. The project was, as you may have guessed, a two-wheeled self-balancing robot via a PID controller:

     
    We used an MSP430G2553 with the EXP430G2 launchpad, although the code should of course be applicable to any similar MCU. We also used the apparently popular MPU6050 IMU to produce angle estimates, and a simple H-bridge using TIP-102 transistors for motor control. The schematic that I've attached is a complete reproduction of our setup (including our pin configuration), and can also be found on the github linked to at the bottom of this post.
     
    The files that describe the primary control sequences are main.c, which of course has the setup and main loop, as well as the PID controller code; and StateEstimate.c, which describes how the raw IMU data is combined into a more accurate estimate of the robot's current angle with the ground (we used the so-called "complementary filter" with reasonable success, which just sums a low-passed accelerometer reading with a high-passed gyroscope reading). Furthermore, the parameters for the PID controller are located in Config.h (the parameters currently in the repo are just toy values), and the parameters for the state estimator are located in StateEstimate.h.
     
    The two biggest frustrations we faced when developing the project was successfully communicating with the MPU6050 over I2C (included in the github is the i2c device library, separately available at http://www.i2cdevlib.com),and getting useful information sent over a UART connection. So, I hope that by releasing this code we can make those tasks at least a little bit smoother for people tackling the same problems. The code is set up, by default, to use pins 1.1 and 1.2 for UART communication over the hardware serial interface. The MSP430 will send the angle estimate and PID control signal over UART, which can be captured and saved as a CSV, or even displayed in an OpenGL gui, using the supplied serialReader.py python utility (instructions are in the repository README). Using the supplied C code as a template, sending and receiving arbitrary data for post-processing should hopefully be trivial. UART is configured in main.c, and the functions for sending data over the connection are located in hwuart.c.
     
    Link to github: https://github.com/austensatterlee/robotbuddy
     
    Anyway, I hope this is helpful or at least interesting to some of you. I'd be happy to answer any questions about how we got this working, or receive any criticisms from more knowledgeable members!

  9. Like
    vinicius.jlantunes reacted to Fred in Apple Watch Teardown : ST Micro + NXP NFC + TI OpAMP   
    They had to cram it in so they stayed under the free size limit in Eagle.
  10. Like
    vinicius.jlantunes reacted to nathancrum in New Dev Platform for MSP430FR5969   
    Hi guys.  It's been awhile since we've posted on this project, but progress has been steadily moving on.  We're working with the Rev 3 prototypes at this point and I think we're pretty close to a final product.  Patrick is going to be out at the Bay Area Maker Faire next week showing them off.
     
    We're also trying to upload stuff as it's stable to github - a few demo projects and an Android app for bluetooth:
    https://github.com/ApparentlyConnected
     
    Shurikens (daughterboards) have expanded now to include a sensor board (RGB, accel & temp), a relay board, an AC rectifier board for use with a current clamp in addition to newer revisions of the LCD, Wifi, and BTLE shurikens.
     
    What kind of demo projects do you guys think would be best to show off the FRAM and low power capabilities of the MSP430FR5969?  Or what demos would you just like to show how it works?
     
    /Nathan








  11. Like
    vinicius.jlantunes got a reaction from bluehash in edx course: Autonomous navigation for flying robots   
    For those into drones, a course just started on edx: autonomous navigation for flying robots. No, you will not learn how to build a drone.
     
    More info here:
    https://www.edx.org/course/autonomous-navigation-flying-robots-tumx-autonavx-0
     
    I just completed the lectures for the first week as well as the homework. Very cool so far. I also like the fact that the course will not be just very high level stuff - they will go through the algebra and technical aspects of it a little deeper it seems (going by the syllabus).
  12. Like
    vinicius.jlantunes got a reaction from bluehash in Cheap solar battery + wireless IoT node   
    @@bluehash, I think it's this one (see message 31).
     
  13. Like
    vinicius.jlantunes reacted to Mark Easley TI in BoosterPack templates in Upverter   
    Hi!
     
    Just wanted to let everyone know that BoosterPack templates (20 pin and 40 pin) are now available in Upverter.  If you haven't tried Upverter yet, its a super cool and pretty polished online hardware design tool that will let you import popular formats like EAGLE and design PCB completely in the browser.  It allows for real time collaboration in the cloud (think google docs for board layout and schematics). Probably something that would be pretty useful for the 43oh community. 
     
    40 pin: https://upverter.com/a-whitehead/9f164fea8af72827/40-Pin-LaunchPad-BoosterPack-Template---AW/
    20 pin: https://upverter.com/a-whitehead/3170001d9dd74890/20-Pin-LaunchPad-BoosterPack-Template---AW/
     
    If you have any feedback on using Upverter, please post it here.  I'm curious to know what you all think about it compared to traditional design tools. 
     
     
     
     
  14. Like
    vinicius.jlantunes reacted to bluehash in PCB Rax - An easy to use circuit board holding system   
    PCB RAX at Kickstarter.
     
    Saw this over at KS.
    ToolGuyd gives his thoughts on the PCB Rax.
     
    Early Bird PCB Rax: $45 (limited to 50 total)
    Maker Level: $55
     
    The PCB Rax ships with the following:
          Two PCB Rax rails made from aircraft grade anodized aluminum     Two 1/4?-20 x 8? connecting rods     Two thumb-nuts     Four PCB extension brackets with hardware
  15. Like
    vinicius.jlantunes reacted to enl in Horowitz and Hill 3rd ed   
    There was a tremendous thump on my porch. The cat spun out hard, regained traction, and headed for under the couch. I opened the door to see the postman walking away and a large box sitting there. I opened it. A gold colored book. The third. has arrived. The cat reappeared, tail fur puffed out more than I have ever seen, sniffed the book, and promptly began dismemberment of the box.
     
    Then began the odyssey: reading the thing
     
    I have only done a partial look through at this time. It will take time. There are a LOT of changes. Much more a new book than a new edition, in many ways.
     
    Highlights:
     
    additional appendices and additions to the old ones. For example, a short intro to Spice. Nice for the students. It is correct, unlike many, many of the online tutorials. A short addition to the o'scope section for digital scopes.
     
    A decent (yes, this I read all of) chapter on microcontrollers. Not detail heavy. A good overview of use, architectures, some examples, a brief comparison guide. Pro: this now in the book. Con: not much to it. It is made up for by updates in the other digital electronics chapters. I will vote overall win, as WAY too broad an area, with too many options that change quickly, for much detail in a long-life, comprehensive text.
     
    New chapter on PLD's that looks good.
     
    Lots of updates to analog chapters.
     
    Missing is the section on construction techniques (unless it was blended into the main text somewhere). That was one of the parts I most often directed students to, as there really haven't been significant changes over the years. (protoboard, PC board, wire wrap, etc, though there have been changes in how frequently each is used with the dominance of surface mount components and easier PC board production compared to 20 years ago)
     
     
     
    Overall review/summary: it was worth the money to update. I have used 1st and 2nd ed.s since they came out as references for all of those things I don't use often, reference tables for part selection, and as references for students to look through. I would still recommend this to a student, in fact more than the outdated 2nd ed, with the caveat that this is NOT a barebones introduction to electricity. It has the target audience (advertising notwithstanding) of a student that has a basic understanding of DC circuits, math at the level of trig (or intro calculus), and basic physics concepts from an intro E&M  course.
  16. Like
    vinicius.jlantunes reacted to enl in Horowitz and Hill 3rd ed   
    I have, to this time, done close review through ch2. I have submit two errata (not bad for first print). There are about a dozen alreadty listed on the H&H site
     
    I have been quite happy with the changes overall, in particular to ch2 (bipolar transistor). I will update as I continue close reading, and would encourage any other that have the text to add their to this.
     
    There is some elaboration vs 2nd ed for switching with transistors, in particular a Schmidt trigger application, as well as a few new things appropriate for low voltage (3v) drive. They open with transistor as a switch, whereas previous editions opened with (linear) current amplifier. A little change in the pure analog side with an emphasis on current source that, to me, fits well with how I have approached things for years. In prior editions, they began with the emitter follower (a good approach when leading to the common emitter amp), but they now break it down into two conceptual pieces explicitly: current source and resistor to convert current to potential.
  17. Like
    vinicius.jlantunes reacted to cubeberg in Working with a Gameboy Printer   
    I've got a lot more work for this project - but I wanted to post what I have so far in case anyone else is interested in the code.
    I started with the Arduino library at https://github.com/davedarko/GBPrinter- which looks like it's based on an earlier AVR project - http://hackaday.com/2010/10/08/game-boy-printer-usb-cable-and-software/
    The library itself need some serious help to make this a "real" library.  Right now - pins are hardcoded, the examples don't work completely, among other things.
     
    So - if you'd like to get this working for yourself - here's what you need to do:
     
    Download the library from Github and put it in your libraries folder.   Crack open GBPrinter.h and change delayMs to 60 instead of 20 Connect GND, and the IN/OUT/Clock pins from the printer to your Launchpad For more information, hookup, etc - you can find a lot on google - but I found this page very helpful - https://milesburton.com/Gameboy_Printer_with_Arduino.  There is a download at the bottom of the page for a word doc.  
     
    From there - the example "GBPrinter" will work for a single "block" print (16x20 pixels).  Open the serial monitor and send a single "h".  The serial setup is a bit odd - so here is a slightly modified version where you see a bit of debugging on startup.  GBPrinter.ino
     
    I've got a few more sketches - one including the 43oh logo - but apparently Google Drive didn't sync them, so I'll have to grab those tonight and post them.  
    Dave Darko's site has some image conversion functionality - but I can't get the applet to work.  There is also a PHP site on the github repo that does something as well.  I wrote a c# converter that I'll be cleaning up and posting later.  
     
    My goal end-project is an internet-connected printer - probably something along the lines of an inspirational quote/image-of-the-day for people who visit my desk at work.  
     
    And here are some pics as proof
     

     
     
     
     
  18. Like
    vinicius.jlantunes reacted to roboteurs in Roboteurs - 3D Printed Robots   
    We've decided to share the STL files for the Print-A-Bot ARM below - you can download them from our website here: http://roboteurs.com...ons/print-a-bot

     
  19. Like
    vinicius.jlantunes reacted to bluehash in Silicon Labs EFM8 microcontroller. Free if you poll.   
    Webinar registration link.
     
  20. Like
    vinicius.jlantunes got a reaction from bluehash in Merged forums support thread   
    Working good on tapatalk as well so far. Good to have the forum back! Thanks B#!
  21. Like
    vinicius.jlantunes reacted to bluehash in NXP and Freescale to Merge   
    Via EE Times
     
  22. Like
    vinicius.jlantunes reacted to Fred in New Launchpad just dropped   
    And now a 30% off deal when bundled with the IR booster pack. Valid until end of Feb.
    http://e2e.ti.com/blogs_/b/msp430blog/archive/2015/02/19/save-money-when-you-buy-msp430-fram-launchpad-bundles
  23. Like
    vinicius.jlantunes got a reaction from bluehash in Products using MSP430   
    The Uni-T UT71E multimeter that Dave Jones didn't like the other day has an MSP430 inside. The meter is bad but at least they use a decent micro :-)
    It's a MSP430FE425: http://www.ti.com/product/msp430fe425
     
    Link to the video - the MSP430 is visible 14:21 minutes into the video.
    http://www.eevblog.com/2015/02/07/eevblog-712-uni-t-ut71e-multimeter-why-uni-t-meters-suck/
  24. Like
    vinicius.jlantunes reacted to adrianF in LaunchPad on Amazon prime!   
    Hi 43oh-ers!
     
    Just wanted to let you all know that we've been working with NKC Electronics to bring the LaunchPad to amazon! Check it out here: 
     
    TI Launchpad MSP-EXP430F5529LP with breadboard and wires bundle

    TI Launchpad MSP-EXP430G2 with breadboard and wires bundle
     

     
    Now you all have more options for getting hardware!
     
    Thanks
    Adrian
  25. Like
    vinicius.jlantunes got a reaction from zeke in Use of Timer A interrupts   
    Just to close the loop - @@roadrunner84 was spot on about my mistake - after fixing that the ISR was executed for all timer interrupts. However, the TAIV switch statement still didn't work, TAIV kept being reset so its value was always zero and neither of the case statements ever got executed.
     
    I then found this article that explains that TAIV, being a read only register, is reset when read; the debugger was therefore resetting it before the switch statement had a chance do to anything useful. That's what I understood at least.
     
    The fix was to use intrinsic __even_in_range. Here is the final ISR code for blinking the LP LED's, one every CCR0 overflow, the other every CCR1 overflow.
     
    p.s.: here is some information on the intrinsic. The first parameter is the string, the second is the last case value in the range.
    #pragma vector = TIMERA1_VECTOR __interrupt void Timer_A1 (void) { switch (__even_in_range(TAIV,10)) { case 2: // CCR1 { P1OUT |= BIT0; P1OUT &= ~BIT6; } break; case 4: // CCR2 { // } break; case 10: // CCR0 { P1OUT &= ~BIT0; P1OUT |= BIT6; } break; } }
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