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hvontres

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  1. Just found 100 20 pin headders for $5: http://www.goldmine-elec-products.com/prodinfo.asp?number=G19546 Perfect for mounting boosterpacks to the bottom of the launchpad
  2. Well, for the original launchpad, the mapping from Processor to pins is 1:1 As stated, this could be done for the newer ones as well. I might work on one for the Tiva C later this weekend. I just happened to be working on a MSP design and thought I'd share the concept.
  3. I played with it a little before, but it seems very bloated and I am not sure it handles multiplexed pins very well. This sheet is intended as an early brain-storming tool where you can very quickly move things around or see why that cool widget you were just going to code up is just not going to work with the parts you have around It seems that Grace is designed for a much later stage in the design process, and at that point it might be useful, but I'll have to try it some more first.
  4. I have attached a simple spreadsheet I am using to plan out how to use the resources on a 430g2553 for a project. It is simply all of the functions for each pin in a seprate cell with a symbolic representation of the chip in the center. The color coding is completely up the the user. This way one can try to make decisions on which peripheral can be used and how it might need to be shared by other functions. I hope this helps The .zip file has both a OpenOffice and an excel version, since I couldn't attache the sheets directly 430G2553_pin_plan.zip
  5. I realize this is kind of an old thread, but I finally got around to re-organizing my space in the garage. Here is the Before Picture, kind of my Bob Pease Memorial Shrine on a desk: Here is the new improved Setup: Note, I have not moved over all of the parts and tools from the old pile yet. I am hoping to keep most of my stuff in the big black cabinet. Most of the stuff here is surplus stuff from work. We are moving to a smaller building, so I scored the ESD safe bench, the cabinet, the two standard monitors, the chair and the magnifier. The scope I got off of Ebay for ~$400 bucks and the supply is an old AT (not ATX ) supply in a custom wood box. The 15" Monitor on the left is for the scope and was originaly a custom monitor in a STEEL box for one of our machines. we decided to go with regular displays instead, so it wound up in the boneyard until we cleaned that out about a year ago Someday it might end up as a display on a mill or somthing more industrial, but I don't know yet. The Computer and the SCSI enclosure were leftovers from IT, as were the tape drive and all of the Hard Drives inside. I am in the middle of upgrading the disk layout since I got a hold of a couple more 18 and 34 GB SCSI drives from the IT pile. The Computer is an old HP workstation with dual PIII 600's inside... I know it's kind of underpowered, but it has two isa slots for my GPIB card and the interface to the universal programmer. And the price was right. I still need to move over my microscope, but I need to figure out exactly where to mount it.
  6. A DC motor (either brushed or brushless) will need some kind of feed back to control position. With a stepper, the encoder can be used for servo like control, or it can be used to detect missed steps after the motion is done. This way, the motor is run in open loop and if there were any missing steps during the move, you could command a couple of extra steps at the end. With a stepper, you are more likely to loose steps at higher speeds, since motor torque falls off pretty rapidly. Having worked around servo systems for the last 18 years, I would not reccomend them for the uninitiated. Proper tuning and hookups can be a real pain without the propper tools. Also, the effects of feedback failures can be very spectacular and dangerous (imagine an axis flying towards you with full torque applied after the encoder fails and then hitting the end stops with a loud bang... that'll wake you up) But for the really adventurous, they do offer the potential for more performance. One of these days I should set up some articles on how a servo system works and can be tuned.... but that would be a bit too much like work
  7. I would suggest a shaft encoder, especially once the new Tiva Launch pads get out. That one will have TWO quadarature counters on board, so interfacing to the encoder should be very simple. As far as controlling the position of a Hydraulic cylinder, you might be better off getting your feedback from the rod itself. One way that I played with years ago while working on the animation system for a Rose Parade Float (http://www.csupomona.edu/~library/specialcollections/rosefloat/floatimages/1993photo.html) is to use a 10 turn pot with a torstion spring, a large wheel and some steel cable. As the rod extends, the pot turns and you get absolute position feedback from the cylinder. I think if you try to just measure the flow, you will integrate up large errors.
  8. Until then, try using ' spi' or ' i2c' as a workaround
  9. UPDATE: I just posted the hardware docs on Github (https://github.com/hvontres/LCD-Controller/tree/master/Hardware/LCD%20Driver) The project was done using the latest snapshot of kicad. One modification that is not shown in the current pdf documents was to remove C6. It seemed to be causing a nasty 20 Hz ripple in the -27 Bias supply that would show up as a 20Hz flicker in the display. I also found a couple of drill holes were a bit small on the first prototype. I will try to get a new version of the gerbers out soon.
  10. There may be licensing issues. The peripheral driver is licensed under a BSD license, but the Grlib and USBlib fall under the "Ti Clickwrap license". this license includes the following clause: This might be keeping that library out of Energia.
  11. well, my two xl120G's are here.... Ship date for my Tiva order is 7/3/2013 so it looks like I'll have fun over the 4th of July weekend
  12. Well, I think I know what happened here... you need to add the Tiva board to your wishlist and then order it. I think I saw the picture at the bottom of the page and added it to the cart not realizing that that was a link to the old EK120XL... so now what will I do with two more
  13. Hmm, that would suck... I just placed a pre-order for two in order to get the Encoder and PWM features...
  14. Actually the display is really dumb. The MSP is in charge of doing the refresh and fetching the data. The Stellaris mostly supplies the memory needed to hold the display data. The Driver chips on the display have enough memory to hold one LINE of data at a time. So the max refresh rate is limited by how fast the MSP can process the data. This display was originaly meant to be driven by something like a SED1335 controller chip. But that would have been too easy By having the MSP handle all of the display timing and refresh, the Stellaris only needs to use ~4% CPU time to manage the display, leaving plenty of CPU time for generating the Data to display. Here is some more info on how to drive this particular display: http://tinyurl.com/8j9jkvv
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