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XBee Tutorial - Chapter 4 Draft "Programming for Data and XBee Configurations" — Parallax Forums

XBee Tutorial - Chapter 4 Draft "Programming for Data and XBee Configurations"

Steph LindsaySteph Lindsay Posts: 767
edited 2010-08-01 22:01 in Accessories
Hi Everybody,

Attached is the draft of Chapter 4, enabled for commenting in Adobe Reader. See the Chapter 1thread for more info about the project. Thanks for the comments so far, keep them coming!

This will be the last chapter posted for a little while, I will be out of the office for a week. You may see Martin Hebel around responding to your comments in the mean time.

An index to all of the chapter draft posts is included in the Wireless Index stickly thread.

Thanks very much,
-Steph

Comments

  • Martin HebelMartin Hebel Posts: 1,239
    edited 2010-07-29 14:25
    Attached as well is the source code for Chapter 4.

    -Martin
  • ElectricAyeElectricAye Posts: 4,561
    edited 2010-08-01 05:54
    First, let me say that I know NOTHING about wireless technology and I've never even wired two Propellers together and used serial communications, etc. so my perspectives are those of a total newbie seeing this sort of thing for the first time.

    Second, I was able to make it through the draft chapters 1 through 3 fairly well. And I'm getting psyched about using these Xbee units. However, when I got to Chapter 4 and started reading how to interface the Xbees with the Propeller, I got totally derailed. I think what bothers me about that section is that you complicate the example by trying to use the Propeller chip in that serial pass-through mode, so that adds a level of complexity to the example that I don't think has to be there. In Chapter 3 you used an example that had the PC communicating to a USB Xbee, and then that USB Xbee communicated to another Xbee. I followed that example quite well. But then in the Chapter 4 example, you have the PC talk to the Propeller which then passes data to a normal Xbee, which then communicates to another Xbee.

    Why not present to the reader an example wherein the PC talks to a USB Xbee, which then talks to another Xbee, which is hooked to a Propeller chip. In that example, let's say a number can be sent from the PC to the USB Xbee, which then sends that number to the second Xbee, which then sends it to the Propeller chip, which then multiplies that number by 10 or something, and then loops the result back so it shows up on the PC. Is that possible? If so, I think that would serve as a better first example, and then, if you want, you can graduate the reader to the Propeller pass-through concept so people don't have to use the USB Xbee version if they don't want to.

    Being a newbie and a non-EE to boot, I always get panicky when too many things are being heaped on me at the same time, so if you can break up the Propeller chip example into perhaps several smaller examples, I'd be much obliged.

    thanks,
    Mark

    smile.gif
  • Martin HebelMartin Hebel Posts: 1,239
    edited 2010-08-01 14:50
    Hi Mark,
    Thanks for the feedback, I thought it was written so that either a USB adapter could be used or using a propeller and serial pass through. I'll look again, but either has the same results.

    Martin
  • treborz17treborz17 Posts: 76
    edited 2010-08-01 15:14
    Martin,

    I am also new but did not fined it too hard to understand, probably because I read what I thought was an excellent description of serial pass through in Chapter 5, that you wrote, in the Parallax Official Guide on the Prop. In fact it seemed like the book treated everything on the XBee a little more thorough than this draft, which probably should be expected in a book versus this paper. Probably the item that confused me even in the book was the use of DL and MY -- I believe that I have it now, the MY is the address to receive data and DL is the data destination address???

    Robert
  • Martin HebelMartin Hebel Posts: 1,239
    edited 2010-08-01 15:32
    Thanks Robert, well, I'm not sure the book treated the XBee better, but in the book I was trying to focus on the Propeller with the XBee as a tool for applications, and in this I am focusing more on the XBee itself and coding for it. * shrugs *

    Yes, MY is the address of that node itself, DL is the address to which you wish to send data - the other unit's MY address.

    -Martin
  • ElectricAyeElectricAye Posts: 4,561
    edited 2010-08-01 16:00
    treborz17 said...
    Martin,

    I am also new but did not fined it too hard to understand, probably because I read what I thought was an excellent description of serial pass through in Chapter 5, that you wrote, in the Parallax Official Guide on the Prop.....

    treborz,

    are you talking about the book, "Programming and Customizing the Multicore Propeller"?
    I would hope that the Xbee documentation is meant to be somewhat stand-alone.


    Martin Hebel said...
    ...I thought it was written so that either a USB adapter could be used or using a propeller and serial pass through. I'll look again, but either has the same results....

    Martin,
    yes, it is written so that either can be used, but that's sorta my point: from a newbie's standpoint you've got too many "you can set it up this way or this way or...." taking place in the instructions. True, from a technical standpoint the results are the same. But from the standpoint of illustrating the concepts to an audience unfamiliar with the technology, I think providing too many options within the flow of instructions starts to cloud what you're trying to say. I think it would be better if those capabilities were broken down into simpler, separate sections. Again, my views are those of somebody not familiar with Prop to Prop communication, but it seems to me your drafts were doing really well until you get to the juicy part in Chapter 4 where you show how to interface the Xbee to a Propeller.

    Just my 0.002 cents worth.

    smile.gif
  • Martin HebelMartin Hebel Posts: 1,239
    edited 2010-08-01 16:15
    Thanks Mark,
    I'm just giving trying to give the user options. I agree the USB Adapter is the simplest and best route, but it's more expense for the end user depending on what they may already have, so I try to write around a variety of hardware that they may have. And between 2 different controllers and 5 different board styles/versions and several other choices, it can get a little convoluted. In "Programming and Customizing" I was able to keep the hardware choices down. Here I am trying to cover a wider range of possibilities leading to being vague in areas.

    I'll see if I can revisit that a little for Chapter 4.

    -Martin
  • ElectricAyeElectricAye Posts: 4,561
    edited 2010-08-01 22:01
    Martin Hebel said...
    ....
    I'll see if I can revisit that a little for Chapter 4.

    -Martin

    Thanks, Martin. Much appreciated. smile.gif
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