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BOE bug ? ? — Parallax Forums

BOE bug ? ?

Don PomplunDon Pomplun Posts: 116
edited 2006-03-22 18:19 in Learn with BlocklyProp
Before I start dissecting my BOE I thought I'd ask if there is a known bug in it. When I DEBUG INH & INL in binary, it seems that when I jumper P13 hi or lo it shows up in the P12 bit position (as does P12).
TIA
Don

Comments

  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2006-03-22 02:33
    Don,

    ·· Are you using a pull-up or pull-down resistor to keep the I/O line from floating?· If not this could cause what you're seeing.

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    Chris Savage
    Parallax Tech Support
    csavage@parallax.com
  • Don PomplunDon Pomplun Posts: 116
    edited 2006-03-22 02:52
    I gave it a try this morning and still find P13 misbehaving. The classroom Lab has many BOEs, but I only have one here at home. Maybe one of the students hooked Vin to an input instead of Vdd. I think pouring superglue down the Vin slots might be an improvement.
    -- Don
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2006-03-22 05:48
    Don,

    ·· Did you try the suggestion of putting the resistors in place?

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    Chris Savage
    Parallax Tech Support
    csavage@parallax.com
  • Don PomplunDon Pomplun Posts: 116
    edited 2006-03-22 15:11
    Yes, of course. That keeps the unused inputs at bay, as predicted. Didn't make any difference putting the probe right on the BS2 sub-board. No way to easily test with the BS2 unplugged. Class starts Saturday. I'll have to try a different BS2 & BOE then.
  • PARPAR Posts: 285
    edited 2006-03-22 15:49
    Don Pomplun said...
    Class starts Saturday. I'll have to try a different BS2 & BOE then.
    And, does this same behavior happen on other pins? I.e., do adjacent pins "misbehave"?

    PAR
  • Don PomplunDon Pomplun Posts: 116
    edited 2006-03-22 16:10
    Nope, only P13, which is what makes me think it might just be this particular unit (since no one has volunteered this behavior as a commonly known bug). Probably some prior year student hooked Vin to the input.
    I constructed a three story "elevator" as a software project for which the expected operation will be something with which the students will be familiar. It uses 14 inputs from various buttons, plus a servomotor oputput. Figured I had a wiring error, but it ends up being this P13 thing.
    -- Don
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2006-03-22 18:19
    Don Pomplun said...(trimmed)
    Nope, only P13, which is what makes me think it might just be this particular unit (since no one has volunteered this behavior as a commonly known bug).
    In more than 11 years in production nobody has ever reported anything like this that I am aware of making it unlikely that it is a bug.· More likely the I/O pin or board was somehow damaged.

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    Chris Savage
    Parallax Tech Support
    csavage@parallax.com
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