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toozie21

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  1. toozie21

    Trouble computing ADC conversion time

    I've been playing with this a little more and am really liking the 430. I am still working my way up the learning curve as knowing where to find things in the datasheets and understanding the differences between the 430 and PIC are still dragging on me. I have been using some of the example programs to familiarize myself with the part and am getting a little more comfortable with the ADC. My problem is that I am still trying to prove to myself that I 1)know how to set it up; and 2) know for a fact how long it is taking between sample/holds by toggling a pin and scoping it, but I guess I still don't quite understand. The example code CC builds up uses interrupts, which is fine (I would want them in the end anyway), but it always doesn't set things up in a simple straightforward manner, so I feel like I should probably rewrite it to do the minimal to setup the ADC12 configurations. Is there sample code anywhere that shows the ADC12 sampling at the default 5MHz that I can use as a basis?
  2. toozie21

    MSP430F5529 USB Launchpad printf

    OK, I think I found what I was looking for. There is the USB backchannel project that TI supplies for the CC IDE. I built it and it allows you to echo transfers characters from the USB back-channel to the MSP USB-serial channel and vice versa. I should be able to take that and rework it for what I needed.
  3. toozie21

    MSP430F5529 USB Launchpad printf

    Well, maybe I should rephrase my question. If I wanted to do something SUPER simple to get started (like poll the ADC, and send the value to the terminal), how would you recommend I get started (this test would allow me to test things, get used to the 430, and have a way to print debug)?
  4. OK, so my Launchpad came in and I finally had some time ot start playing with it and learning the 430. I've been mucking with the example codes to try and get my feet wet, but I am having no luck with the hello.c hello world application. How is that supposed to work? I figured it is using printf() to send the string out the USB port, so I setup a serial terminal to look at the port at 9600, 57600, and 115200 baud and didn't see anything coming out? Is there something I am missing for what I need to do here? I am using CCS as my IDE. Thanks!
  5. toozie21

    Best compiler to get started with?

    Hmmm, lots of good info. I guess for now I will go with one of the free ones which will be more than good enough to make sure I know everything and then move on from there. At that point I guess I can try to figure out if I am comfortable enough to use the GCC, or if I can talk my work into investing some money into software for a little side, after-hours research project. Thanks guys!
  6. toozie21

    Trouble computing ADC conversion time

    OK, I guess I am still a little lost. If I say 17 clocks for 10-bit, and running at 5MHz, that would be 17/5MHz, that is nearly 300ksps. I guess the math works out that way, but I should just assume that anything above 200ksps is null and that that is really the upperbound?
  7. I've been reading up on the 430 on the USB LaunchPad and am having a little issue figruing out the conversion time for the ADC. I feel like I must be missing something, but here is what I saw: The sample rate depends on the resolution. The ADC supports 8-bit, 10-bit, and 12-bit resolution modes and the conversions require 9, 11, and 13 cycles, respectively. The 430 can run up to 25MHz on the LaunchPad. The datahseet claims greater than 200ksps maximum conversion rate. So if I look at the best case scenario of 8-bit ADC running at 25MHz, I think that equates to 1/(25MHz*[9 cycles]) = 2.778msps, which obviously is not accurate. So what am I missing?
  8. toozie21

    Best compiler to get started with?

    Very cool. So no need to worry about TDI/TDO, etc? It does it all through the Test and rest lines? Then external 430s can be programmed and debugged? What are you currently using to build your devices?
  9. toozie21

    Best compiler to get started with?

    I've generally been a PIC man, but I want to branch out into the 430 for some low power battery applications I have been thinking about. I was eyeing up the MSP430F5529 USB LaunchPad as a starting eval board as it is priced REALLY well, and looks like it should do most everything I need to get started. I've used a 430 once in the past in a class (about 3 or 4 years ago), and it was OK, but I spent a LONG time futzing with the gcc tools to get it working. So now that I am starting fresh. What do people recommend? Go the gcc route again, or maybe pick up one of the freebie crippled ISEs that are out there and go that route? Also (slightly off topic), once I get started, is there a large investment when I move to custom boards (I am thinking of the programming and debugging aspect)? That won't be an issue while using the LaunchPad, but once I build something up, I don't know how hard it is migrate over (programmer, extra peripherals on the PCB, etc.).
  10. Ah, you are right. I had done a bunch of research on this about a year and a half ago and forgot that that was one of the reasons I abandoned the 433MHz process. You got me thinking about it again and I totally glossed over that stuff. I had actually wrote Anaren on Saturday to see why they didn't have FCC pre-certification for their 433MHz AIR parts (like they do for their 915MHz), and this was their response (hint: it plays RIGHT into what you were saying): In my case, it won't be event driven in the pure sense, it will be reporting in on a set time interval. So if I remember correctly, it didn't seem to keep with the essence of what the FCC wanted to see in that band. So in the end, I guess that gets me back into the 915MHz band, right? <<An aside>> I got that Anaren response on the same day (Saturday) and when I asked it. The couple of times I wanted clarification or some more information from them that isn't in the datasheet, they have been very responsive and accommodating. I've been highly impressed.
  11. Yeah, I was pretty disappointed with the range, but the price and FCC approval is pretty sweet. Not much else out there that I saw (hence the post) that hit the price point and had approval though.....
  12. The first set of module I had of Anaren's had that built in loop antenna on the PCB. I carefully laid out the board to accommodate it per their recommendations, but the range on it really was sub-par in my opinion (good enough to do some stuff in a house though if that was all you needed). If I stick with anaren, I will need to throw an omni onto there.
  13. Thanks for having me, someone over on the dangerousprototypes forum turned me onto this site. I appreciate the help. I am in the US and definitely want to play nice with the FCC. What modules to you recommend in the 433MHz range? Anaren has one, but it only has EU approval for some reason. That would be a pretty good instructable!
  14. I am currently playing with a nifty little module from Anaren called AIR (2pg pdf:http://www.anaren.com/sites/default/files/Part-Datasheets/A1101R09C.pdf), for a low-power embedded project and it works OK; but I was wondering if anyone else had experience with any other like type modules? My loose requirements are that I would like to reasonably (not pie-in-the-sky) hit 1/4 - 1/2 mile distances at slow speeds (9600 baud is fine). I would like to use an omni antenna (so no high directional antennas), would prefer the module to have pre-FCC approval, and would like the modules to be less than $15. Lower the power draw the better, but we know how that trade-off works! Those requirements really limit me, but the Anaren part seems like it could cover them; I am just curious what other things are out there that I might have missed. I am not married to the 900MHz spectrum, it just seemed like the most likely place for me to meet my goals. This is for an outdoor transmission.
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