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Everything posted by VirtualEnder

  1. I'm attempting to add support for a pseudo digital protocol to a project of mine. I'm attempting to implement the dShot protocol for controlling ESCs on my thrust stand, and having some issues. The TivaC doesn't appear to have very robust output control. You can see what I'm trying to do here: https://github.com/VirtualEnder/TestStandv2/blob/dev/MQTB_Thrust_Stand/hardwareTimers.ino Basically the protocol uses a modified PWM signal with each bit being 1.67us period with 1250ns representing a 1 and 635ns representing 0, basically encoding a 2048 bit throttle signal with some CRC data and a telemetry call bit crammed on the ends. After a couple days I've gotten to the point of using a PWM timer synced with a GP timer to attempt to modify the duty cycle for each bit, however I'm not having much luck. Is there a more precise way of accomplishing this? I'd like to not have to switch MCUs, but I know the ESP32 can do this easily with their RMT methodology and the STM chips can do with with a DMA transfer. I looked at the uDMA implementation in the TivaC and it doesn't appear to operate in a way that would work to toggle pins like this. This is the output signal I'm getting on my relatively limited DSO Nano from the TivaC: And this is the output signal as seen from an STM32F405 that is working properly: Any help would be very much appreciated.
  2. Awesome thanks so much for this! Will this be included in the next Energia release? Been waiting for this for a while!
  3. Is a mode for steppers provided by the driver chips, or do you have to update each step via i2c? I'd love to be able to simply set a speed and direction via i2c and not have to drive each step! Also will these be stackable at different i2c addresses?
  4. Great to hear. I'll be interested in watching how adoption of Arduino by other boards goes with this new framework in place with 1.5. They Arduino folks have really been pushing the idea of making it easier to port, so we'll see what happens. I'm excited about the option of having more boards easily accessible for education and early introduction to electronics. This has all kinds of implications for STEM education as well as high-school and up.
  5. I'm also curious what the release of Arduino 1.5 today means for Energia. From my reading of the documentation, it looks like they have built in structures to the new Arduino to simplify porting it to new architectures. I'm curious how you guys will approach that, if you are considering wrapping your port work into the new Arduino or continuing to develop Energia as a separate project.
  6. Are you going to be driving the motors using io operations? How fast can the 430 cycle pins? Also how are you handling acceleration for the steppers? Nice work though, it looks really well thought out!
  7. I recommend TeraTerm as a simple serial terminal. Very flexible and easy.
  8. That's so weird, I ordered mine the same day (Aug 31) at 2:30 in the afternoon and I got mine Oct 5th. Strange!
  9. Will this be able to drive bipolar steppers? Looks like you could drive two possibly?
  10. I've got two of the Anaren booster packs for the MSP430 if anyone wants me to test some code on those.
  11. TI Specified a potential ship date when I first ordered mine and it shipped out exactly when they said. Shipped on the 3rd of Oct, in my hands on the 5th!
  12. I managed to solve the undefined error by moving my interrupt handler into a separate C file and moving my constant definitions out into a separate header file. Seems to work OK! Moving on!
  13. Well I feel kind of stupid, Dan helped me out on his blog. I just had forgotten to switch the primary file over to a .cpp (C++) so his object for the display was throwing errors! The library he wrote is accessed by including the header file in your main C++ file. Thanks to Dan for helping me out with that bit. (note to admins, he said he's having trouble getting his account activated on this site :| someone should check that out, he rocks!) That fixed the problems with the display, now I'm getting an error on the interrupt handler. Since I've added the display code it says my IntHandler (Timer0IntHandler) is not defined even though it's defined directly above my main function. Also thanks for the advice jazz. I'll probably just keep the code on the uC to simply axis, direction, step and write the gCode in software then. I'm looking to build a full CNC for wood/acrylic/aluminum etc. I'm using big Nema23 steppers with massive torque I'm looking to interface with common CNC software as well. I'm sure it'll be a huge project, and I may end up dumping everything I'm working on now and re-doing it, so we'll see. It's just a fun project for now.
  14. Here is a code library for a 7seg display/led/button module available cheaply on dealextreme. Code works well and I've found it useful, though I've had some trouble integrating it into other projects. Credit goes to Dan Oprescu (robotrandi <at> gmail <dot> com) http://trandi.wordpress.com/2012/10/11/tm1638-display-driver-for-stellaris-launchpad/
  15. Hi all! The current project I'm working on with Stellaris is a stepper (step, direction) driver. I have these TB-6560 drivers that I got on eBay for cheap (here), and I've successfully driven the motors using the 32 bit timer. I've been able to set the frequency using a variable, etc, and hoping to implement acceleration, etc. The goal is to eventually write an entire gCode interpreter and be able to drive the CNC via a serial connection that dumps gCode to the Stellaris. I'm running in to a weird problem though. I'm attempting to add a control panel I got form Deal Extreme that connects via software SPI. I've been able to successfully interact with it using a library developed by Dan Oprescu. Works great in its own CCS project. I can read buttons, update the 7-seg displays, light LEDs, and everything works great. I've moved his library into my stepper project, and all hell breaks lose. As soon as I include the TH1638.h header in my stepper project I get hundreds of build errors. The really weird part is they don't seem to be coming from any of my code files. They are all coming from compiler includes in iosfwd and exception. I looked around on the web and I found something about including pre-compiled headers being a problem, but I'm a bit lost in this. I compared all the CCS project settings between the TM1638 project example, and my stepper project, and nothing seems out of place. I'm sure I'm missing something, but I have no clue how to debug this. If anyone has any ideas that would be greatly appreciated. I've attached my code so far if anyone has a few minutes to look it over! I'll keep posting here as I progress through the project as well! Suggestions and pointers welcome! EDIT (10-15-2012) Here's (attached) the latest updates to my code with the solutions listed below, if anyone is interested. I'll probably copy it over to github and then post it under the code section before too long here. I want to get it a little further before I do that. I'm sure I'm doing some things wrong here and I may have to change approaches, but this is what I've got so far! EDIT 2 (10-15-2012) Here is a link to the project git repo. Feel free to clone and code! https://github.com/VirtualEnder/Stepper Stepper.zip
  16. Hi all! First off I'd like to say thank you to the developers and hosts of this forum! I hope it turns out to be as vibrant and helpful an online community as so many of the other micro-controller user forums. I'm thoroughly enjoying my experience with the Stellaris Launchpad so far. This is my first major exploration of lower level coding. I have extensive experience with Arduino and derivatives, but I figured it was about time I start looking more into lower level interaction with the hardware. It's been an adventure so far! I'm realizing how much I don't know about how an architecture is put together and how to work in the commercial development platforms. I've managed to get a good bit working, but I feel a bit like I'm stumbling around in the dark! It's good for me though! Once again, I'm looking forward to being part of the community here and hopefully we can all make this a great place!
  17. I think that 3.3V is enough to power the MAX232 but the margin is very close. 3.0V (or less depending on charge) seems to be below the margin. Using a wall wart will supply a constant 3.3V through the regulator that seems to be enough to trigger the logic on the MAX232. I think the FTDI entered the conversation as a way to allow you to program the chip without having the emulation side connected in order to save power if using a battery. The MAX3232 might be a valid option to allow the device to work on the battery running at or below 3.0V.
  18. Thought everyone might like to know I got the AccelStepper (http://www.open.com.au/mikem/arduino/AccelStepper/) library working without any hiccups. I'm using a cheap eBay driver with a pretty beefy 3A Nema 23 stepper. Looking to build a CNC eventually. Just playing at this stage but it seems to work well with the launchpad. I'm running at setSpeed(1000) without trouble. I think the opto isolation on these chips is a bit iffy (get what you pay for) so fast acceleration seems to skip some steps, but that's manageable. Thanks again for all the work by the Engia guys!
  19. It sounds like the battery voltage is not enough to power the MAX232. Try plugging in to a USB wall charger rather than battery power. Unless there is some specific need to use battery, it's much more reliable. I'm assuming since this going right to the printer it will be near an outlet.
  20. Anyone have an AIR BoosterPack library in the works? I've got two of these and I'd love to get them talking using Energia! I love this project! Keep up the good work guys!
  21. Let me tell you how long I have been waiting for someone to do this! The MSP430 is a great chip and the launchpad is a great board! The traditional tool-chain is pretty horrible though, especially for new users! Now we have a great development environment to work with! Finally we have a cheap low power solution with a great IDE right in the hobbyist usability range! Thank you thank you thank you! I'll be excited to watch development continue and this project mature! Keep at it!
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