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Did I just smoke my Propeller Development Board? — Parallax Forums

Did I just smoke my Propeller Development Board?

ElectricAyeElectricAye Posts: 4,561
edited 2009-03-03 13:45 in Propeller 1
Okay, so I'm dumb. I started working with the Prop Development Board for the first time and I figured I could use a generic wall wart I had laying around, which said it had the right voltage and amps. Long story short, I found out that, although it plugs into the Prop Dev Board ever so nicely, it has a polarity that is reversed from that required by the Prop Dev Board. Stupid me, I didn't even know such a polarity reversal was possible. After all, electronics people are smart, and surely they wouldn't use the same connector for different polarities... right?

Question is: did I ruin my Prop Development Board? or does it have some sort of built-in anti-idiot robustability?



cry.gif

Comments

  • mctriviamctrivia Posts: 3,772
    edited 2009-03-02 00:33
    probably killed the prop only but some like spin studio have anti ideat protection. try programing it

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    Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.

    Post Edited (mctrivia) : 3/2/2009 12:38:19 AM GMT
  • mctriviamctrivia Posts: 3,772
    edited 2009-03-02 00:43
    is the prop soldered on or dip package in holder? if you have fried the prop and it is the qfp package I can replace it for 20 canadian I have some spares

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
  • Cole LoganCole Logan Posts: 196
    edited 2009-03-02 00:44
    I would give it a shot I made the same mistake on a protoboard and it still works fine.
  • PhilldapillPhilldapill Posts: 1,283
    edited 2009-03-02 00:52
    I've done that on my PropBoard, but apparently, I was super wise in my choosing of voltage regulators. The regulator got PRETTY warm for a few seconds until I realized something was wrong. My plug was reversed and I hit it with 12VDC from the walwart. Not a problem though - my propeller was fine and so was my regulator!

    Can't hurt to see if it still works, right?
  • ElectricAyeElectricAye Posts: 4,561
    edited 2009-03-02 01:20
    Philldapill said...

    Can't hurt to see if it still works, right?

    Can't hurt but it means I have to drive out and buy a new wall wart.... when the other option is to abandon the Prop Development Board and go for a different package for the Prop. I just wanted to know what the chances are that I sizzled it. skull.gif
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2009-03-02 01:26
    ElectricAye said...
    After all, electronics people are smart, and surely they wouldn't use the same connector for different polarities... right?
    The original designers who used coaxial power connectors, indeed, were smart and made the center negative and the shell positive. This was smart because it enabled a mating jack having auto-break contacts to break the positive side of the circuit instead of the negative side. But someone, somewhere along the line (about the time Radio Shack came out with their Model 100 portable computer — not that they're to blame, but their 6V center-positive wall transformer has to have been influential) decided that it was "unnatural" to have negative in the middle and switched polarities. Unfortunately, "natural" has trumped "logical" ever since.

    -Phil
  • mctriviamctrivia Posts: 3,772
    edited 2009-03-02 01:40
    you can just cut the wires to wall wort then swap and solder back together

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
  • ElectricAyeElectricAye Posts: 4,561
    edited 2009-03-02 02:32
    mctrivia said...
    you can just cut the wires to wall wort then swap and solder back together

    Good idea. Luckily I found a wart that works and the PDB seems to have survived my ignorance. I guess it's best to presume NOTHING when making connections with found components.

    Thanks everyone,

    Mark

    smile.gif
  • mctriviamctrivia Posts: 3,772
    edited 2009-03-02 03:28
    i had to do that myself. the box said positive center but it was not.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
  • Carl HayesCarl Hayes Posts: 841
    edited 2009-03-02 05:50
    Clearly the 3.3v regulator survived. Were I you, I would do a quick check to be sure the 5v regulator is OK too. Nothing on the PDB uses 5v, but they provide a 5v regulator for things you plug into the solderless breadboard. Wouldn't want a surprise at some future time.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    · -- Carl, nn5i@arrl.net
  • Carl HayesCarl Hayes Posts: 841
    edited 2009-03-02 05:56
    On my own designs, I like to include a series diode to protect against reversed power.

    I hope you don't have to be dumb to hook things up backward, for I did it yesterday to an LCD display that plugs into a 2x5 Berg header on my Prop design.· It was like that for about a minute or more while I tried to figure out why it was just flashing instead of showing the expected display.· At length I said "oh, my goodness" or perhaps something stronger, turned off the power, hooked it up right, and -- mirabile dictu·-- it still worked.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    · -- Carl, nn5i@arrl.net
  • ElectricAyeElectricAye Posts: 4,561
    edited 2009-03-02 06:28
    Carl Hayes said...
    Were I you, I would do a quick check to be sure the 5v regulator is OK too.

    Thanks, Carl, that sounds like very good advice.


    smile.gif
  • kwinnkwinn Posts: 8,697
    edited 2009-03-02 15:32
    A diode or even better a bridge rectifier on the power input would solve that problem. Yes I know it adds to the cost but imho it's worth it in the long run.
  • mctriviamctrivia Posts: 3,772
    edited 2009-03-02 15:44
    it adds to the cost but also wastes more power. a bridge rectifier drops 1.4V

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
  • Carl HayesCarl Hayes Posts: 841
    edited 2009-03-02 19:47
    mctrivia said...
    it adds to the cost but also wastes more power. a bridge rectifier drops 1.4V

    No, it doesn't waste more power.· Whatever it drops, would be dropped by the regulator if the protection diode were not there.· You do need to be sure, of course, that the supply voltage is not so little above the regulator output that you don't have enough for two drops.· But assuming the input is sufficient, the diode will waste no power at all.· None at all.· None.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    · -- Carl, nn5i@arrl.net
  • mctriviamctrivia Posts: 3,772
    edited 2009-03-02 19:53
    I use a switching power supply so it does but you are correct for linear

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
  • mctriviamctrivia Posts: 3,772
    edited 2009-03-02 19:56
    I do use a shotkey diode as polarity protection on wall side though. battery side just reliy on picture to protect.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
  • Ken GraceyKen Gracey Posts: 7,400
    edited 2009-03-02 20:00
    ElectricAye,

    If you really damaged the board we would replace or repair it for you, often for free. After seeing how you sluethed your way through this with the help from the forum we have nothing but support for you should you need to call upon us for repair or replacement.

    Ken Gracey
    Parallax, Inc.
  • jazzedjazzed Posts: 11,803
    edited 2009-03-02 20:10
    That is very of you Ken. Will you replace my hacked up protoboard? (just kidding)

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    --Steve
  • dMajodMajo Posts: 855
    edited 2009-03-02 21:03
    If it is a PPDB it have 2 linear regulators in series (I own one). Maybe you have fried the first one (the 5V) but for sure (ok ... I will not put my hand on fire) the prop is good and the same for most of the equipment since it is not supplied (you need to wire them when you use them)

    I wish you goog luck
  • mctriviamctrivia Posts: 3,772
    edited 2009-03-02 21:09
    lot better then my offer and I was offering almost cost

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Need to make your prop design easier or secure? Get a PropMod has crystal, eeprom, and programing header in a 40 pin dip 0.7" pitch module with uSD reader, and RTC options.
  • ElectricAyeElectricAye Posts: 4,561
    edited 2009-03-03 13:45
    Ken Gracey (Parallax) said...
    ElectricAye,

    If you really damaged the board we would replace or repair it for you, often for free.....

    Ken Gracey
    Parallax, Inc.

    Hi Ken,

    that's a mighty generous offer you have there, but I certainly am not blaming the design of the Propeller Development Board for my stupid mistake. I should know better than to blindly connect things together like I did. In any case, your design seems to have survived my careless attack.

    thanks!

    Mark

    smile.gif
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