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Basic Stamp not found and overheating — Parallax Forums

Basic Stamp not found and overheating

vk1222vk1222 Posts: 6
edited 2011-02-24 10:50 in BASIC Stamp
This is my first post but I've been browsing through these forums for my projects. I'm pretty new to microcontrollers but I have been around circuits so I'm not completely unknowledgeable. I have run into a problem with my bs2 module on my USB board of education. I had a circuit consisting of 3 IR sensors that were connected to the servo ports and 2 LED lights connected to P0 and P1 with a 9V AC plug. There were no resistors or anything else in the circuit and it was working find for a while, but when I turned it on today and tried to upload a the program again it said "No basic stamp found" and I noticed that the module is heating up. It seems that the black chips under the "BS2" and "Rev J" seem to be the ones heating up but I can't tell for sure. I have included the code I was running too. I hope the chip isn't fried but I've changed everything.

' {$STAMP BS2}
' {$PBASIC 2.5}
OUTPUT 0
OUTPUT 1
LED CON 0
LED1 CON 1

Initial:
LOW LED
HIGH LED1
PAUSE 1000
GOTO Sensor

Sensor:
DO
DEBUG "Pir2:"
DEBUG BIN IN15, CR, LF
DEBUG "Pir2:"
DEBUG BIN IN12, CR, LF
DEBUG "Pir3:"
DEBUG BIN IN13, CR, LF
PAUSE 100
IF IN15 = 1 THEN Flash
IF IN12 = 1 THEN Flash
IF IN13 = 1 THEN Trip
LOOP

Flash:
HIGH LED
LOW LED1
PAUSE 7000
GOTO Initial

Trip:
LOW LED
PAUSE 100
HIGH LED
PAUSE 100
LOW LED
GOTO Sensor

Comments

  • Mike GMike G Posts: 2,702
    edited 2011-02-22 16:30
    Disconnect the circuit and try loading a simple program. If it works then you have a problem with your circuit. Otherwise, there could be a problem with STAMP.
  • vk1222vk1222 Posts: 6
    edited 2011-02-22 16:39
    I have already tried that. I cannot get a connection to the stamp when it is just the powered board either.
  • Mike GreenMike Green Posts: 23,101
    edited 2011-02-22 17:18
    The most common causes of "Stamp Not Found" are: 1) Lack of power to Stamp; 2) No serial communications with Stamp, usually due to bad cable, or a problem with USB to serial interface.

    Neither one causes the Stamp to overheat. I always get worried when someone talks about using a 9V AC plug since the fastest way to destroy a Stamp is to connect it to an AC power source, but you didn't describe how you used the "plug". I suspect your Stamp is damaged. Call Parallax Tech Support tomorrow for assistance.
  • Mark KiblerMark Kibler Posts: 546
    edited 2011-02-23 18:17
    I had a circuit consisting of 3 IR sensors... with a 9V AC plug. There were no resistors or anything else in the circuit ... and I noticed that the module is heating up.
    I think you might have cooked something by not using resistors and by using a 9V AC input. It seems diagnostic that you said,
    "It seems that the black chips under the "BS2" and "Rev J" seem to be the ones heating up.."
    These are the ones that I suspect may be burned up.

    Yes, try running a simple program to see what happens. If it doesn't work just call Parallax Tech Support.

    Good luck,

    Mark
  • vaclav_salvaclav_sal Posts: 451
    edited 2011-02-24 10:50
    "2 LED lights connected to P0 and P1 with a 9V AC plug. There were no resistors or anything else in "
    Really??

    Connecting LED directly to Stamp is asking for trouble.
    It may work for a while since Stamp limits the output current ( per pin and per all output) , but it would definetly get warm.
    Your LED output needs to have a current limiting resistor - depending on the LED requirement - 1KOhm may do.
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