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Have I burned it up? — Parallax Forums

Have I burned it up?

FatfendersFatfenders Posts: 39
edited 2007-05-25 17:29 in BASIC Stamp
Been playing around with my new BS2... things were going great, then all of a sudden, when I try'n load my program I get 'No basis stamps found'. 'Identify' still get 'yes -yes'. While I have never touched it before, when I pressed down on the stamp I was surprised as to how hot it was.
Dave··

Comments

  • sam_sam_samsam_sam_sam Posts: 2,286
    edited 2007-05-24 02:54
    Dave

    What did you have hook up to the Basic Stamps Pins

    What code where you using

    What power supply are you using

    You need to give us more Detail on what you where do with the Basic Stamp


    What dose the Basic Stamp·do now that it has cool down
    ·

    Dose the Basic Stamp do now if you power it up

    Dose it get hot now with nothing hook to its pins

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    ··Thanks for any·idea.gif·that you may have and all of your time finding them

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    Sam

    Post Edited (sam_sam_sam) : 5/24/2007 3:03:54 AM GMT
  • FatfendersFatfenders Posts: 39
    edited 2007-05-24 03:09
    I had it in my car. I have wired 12v to a 9v regulator for power. Pins 12, 13, 14, are driving LEDs. Pins 10 and 11 read a high or low from·2 5v relays. I bench checked the heck outa this thing. Worked as I wanted through several tests.
    The code tested pins 10/11 for low/hi, then lit up the LEDs accordingly.

    If I turn it·off, wait a bit, then turn it on, within a few seconds the top (where the 'BS2' is printed) get to hot to touch, the bottom part gets hot but I can still touch it.
    The code looks like this...
    A_solenoid PIN 11
    B_solenoid PIN 10

    second_gear PIN 12
    third_gear PIN 13
    fourth_gear PIN 14
    prev_gear VAR Byte
    DO
    ·IF···· A_solenoid = yes AND B_solenoid = yes THEN Gear = 1···· ' Set first gear
    ·IF···· A_solenoid = no· AND B_solenoid = yes THEN Gear = 2···· ' Set second gear
    ·IF···· A_solenoid = no· AND B_solenoid = no· THEN Gear = 3···· ' Set Third gear
    ·IF···· A_solenoid = yes AND B_solenoid = no· THEN Gear = 4···· ' Set Fourth gear
    ·IF prev_gear <> Gear THEN
    ······ prev_gear = Gear
    ······ LOW second_gear
    ······ LOW third_gear
    ······ LOW fourth_gear
    ······ IF Gear > 1 THEN HIGH second_gear
    ······ IF Gear > 2 THEN HIGH third_gear
    ······ IF Gear > 3 THEN HIGH fourth_gear
    ······ DEBUG "shift into ", DEC Gear,CR
    ·ENDIF
    ·PAUSE 100
    LOOP·
  • FatfendersFatfenders Posts: 39
    edited 2007-05-24 03:15
    Forgot... removed all pins,·same drill when turned on. Top gets too hot to keep·touching.
  • sam_sam_samsam_sam_sam Posts: 2,286
    edited 2007-05-24 03:15
    Dave

    How·did you have the 2· 5 volt relay hook to the Stamp pins

    How·did you have the Leds hook to the·Stamp pins·

    What Basic Stamp Board are you using

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    ··Thanks for any·idea.gif·that you may have and all of your time finding them

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    Sam

    Post Edited (sam_sam_sam) : 5/24/2007 3:24:24 AM GMT
  • FatfendersFatfenders Posts: 39
    edited 2007-05-24 03:36
    Again, all this stuff worked fine through many, many tests.

    The NC contacts on the 5v relays·a wired to Grnd. The NO contacts are wired to 5v+. One side of the coils is wired to 5v+, the other to an external switching device. The common pins are·wired to i/o pins 10-11, respectively.

    3 of the LEDs are simply wired to pins 12-13-14 (+ side)... - side direct to Grnd.·1 LED is hard wired·to 5v+ and ground.

    I am using the 'Board of Education'

    Thanks,

    Dave
  • sam_sam_samsam_sam_sam Posts: 2,286
    edited 2007-05-24 17:15
    Dave

    This can be found at

    http://www.parallax.com/dl/docs/books/edu/wamv2_2.pdf

    Page 84·· What's a Microcontroler ?

    ········470 Ω
    P14...^^^......LED.......Vss

    ········ 470 Ω
    P15...^^^......LED.......Vss

    If you hook the leds the way that you have here
    Dave

    3 of the LEDs are simply wired to pins 12-13-14 (+ side)... - side direct to Grnd.·1 LED is hard wired·to 5v+ and ground.



    · If you did not put a Resistor in your Led Circuit then you over load the pins

    On the Basic Stamp

    ·Dave

    ·The common pins are·wired to i/o pins 10-11, respectively.

    What's a Microcontroler ? Page N\A

    If you powered the relay the same way then you·Over Load the those

    Pins the same way they need a Transistor to drive the relay



    You may have damage your Basic Stamp if you hook it the way you said that you did







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    ··Thanks for any·idea.gif·that you may have and all of your time finding them

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    Sam

    Post Edited (sam_sam_sam) : 5/24/2007 5:31:37 PM GMT
  • FatfendersFatfenders Posts: 39
    edited 2007-05-24 18:24
    Sam,Thanks for that.

    I do have resistors in the LED's but·I wired the coils of the 2 5v relays such that·1 side is to (switched) grnd and the other is to the 5v Vdd pin on the board. But I think that is where·I messed up. The contact pins are (NC) grnd or (NO) Vdd 5v to i/o pins 10/11. I don't see a problem with that. But here is where I·think I burned it up...

    The TCU closes to·Grnd when it commands a solenoid ON. The other side of the solenoid is connected to a constant 12v+. (there a 2 solenoids that operate this way)

    I just taped into each wire out of the TCU but as a reviewed my efforts this AM I realized what·think happened is, when I hooked everythink up for 'real' the first time, I instantly fried the unit.

    You see, to test, I just held a grounded lead to the switched side of the relay coil(s). LED's worked as desired.

    But when I hooked it up 'for real', as soon as I turned the key on, I think the constant 12V wired to the solenoid(s) fedback, through the solenoid coil, throught the wire to the TCU, and my 'taped' wire, through the 5v relay coil, then on into the 5v Vdd pin on the board, in effect, pushing 12v into the 5v Vdd output pin. Of course, I don't know what effect pushing 12v into the 5v Vdd pin has but my best guess is, it's not good.

    This, for sure,·ain't my first screw up projecting, no big deal. But I gotta say, fool'n around with this microprocessor stuff (for the first time) is waaay more fun that I had imagined!

    I live not far from Parallax so I am going over there this afternoon for a replacement.
  • allanlane5allanlane5 Posts: 3,815
    edited 2007-05-24 19:43
    Yup, putting 12 volts on the VDD pin will fry the BS2.
  • FatfendersFatfenders Posts: 39
    edited 2007-05-25 00:10
    Just got back from my run to Parallax. Gotta say, Wow! What service!. 'Dave' disappeared with my board/stamp for a bit, returned to say I had smoked 'em both. But he gave me a·break·on the replacements and even tossed in an old board with some bad pins for me to play with.

    OK, on the the "B" model. This one will have no, I repeat, NO common ground between different voltages!
  • skylightskylight Posts: 1,915
    edited 2007-05-25 07:24
    just one more thing make sure you have protection diodes across the coils of the relays to stop back emf solid bar marking·on diodes towards the relay positive termination blank end of diode to ground connection. see manual for connection examples.
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2007-05-25 14:15
    If you can post a complete schematic of the circuit we might be able to spot any potential pitfalls in it. Take care.

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    Chris Savage
    Parallax Tech Support
  • allanlane5allanlane5 Posts: 3,815
    edited 2007-05-25 14:20
    Actually, you MUST have a common ground between different voltages, if the BS2 is going to control those different voltages. What you must NOT do is put the 12 volt line onto the Vdd pin.
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2007-05-25 14:23
    If you want to avoid a common ground you could use a DC-DC converter and optical isolation on the I/O.

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    Chris Savage
    Parallax Tech Support
  • FatfendersFatfenders Posts: 39
    edited 2007-05-25 16:37
    On 'no common ground'. Yea, I realized soon after I posted that was a dumb thing to think/say. I realize the important thing is isolate any different voltages. Having thought this through I think I can stay out of trouble now. In any case I should be able to 'test for real' today.

    Attached is the failed "A" model and new improved "B" model. I changed over to 12V relays and placed a diode in front of Vdd. The diode is not really required here but now I am runn'n scared just a bit and really want to 'play it safe'.
    4L60-e actual gear.jpg
    465 x 1309 - 65K
  • FatfendersFatfenders Posts: 39
    edited 2007-05-25 16:47
    The previous attachment is too difficult to read so I changed to PDF format here.
    pdf
    pdf
    4L60-e actual gear.pdf
    34K
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2007-05-25 17:29
    Hello,

    Your schematic doesn’t show your power supply system, which, as I understand was part of your initial problem. I would include that as well since car voltages can exceed 14V.

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    Chris Savage
    Parallax Tech Support
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