VIN not working?

[digistump]

That's very strange - and of course if they are defective (which does seem unlikely - but anything is possible) we'll replace them.

Can you send us an email with your order id or full name to support at digistump dot com - maybe we can start by sending you one that we test and confirm works fine with a 9v for us - and go from there.

Thanks,
Erik

[exeng]

Forgive me for the dumb question. But are you absolutely sure that you are connecting to VIN and not the 5V side?

[NeuroJoe]

Forgive me for the dumb question. But are you absolutely sure that you are connecting to VIN and not the 5V side?

Not dumb, completely reasonable. I've tried both the 5V and VIN pins with regulated 5V and 12V battery (respectively) power, both exhibit the same problem. I know it's right because once (and only once) I released the magic smoke by connecting the 12V battery to the 5V pin.  I discarded that one, but the problem continues on the other new sparks I've tried.

Joe

[exeng]

I'd be tempted to use a voltage meter to see if you are indeed getting 5V on the output of the regulator when using VIN.

[NeuroJoe]

I'd be tempted to use a voltage meter to see if you are indeed getting 5V on the output of the regulator when using VIN.

4.76V output from the regulator on USB 5V
4.98V output from the regulator on 5V regulated using 5V pin
5.03V output from the regulator on 12V battery power using VIN pin

Sketch still no worky  (except over USB 5V, which as always is fine). Tested multiple sparks.

Sent you an email Eric, testing one here that you test as fine sounds like a good idea.

Thanks,

joe

[NeuroJoe]

Eric or anyone else, which two (of the 4 total) USB contact strips carry 5V to the chip? I'd like to try applying regulated 5V via that pathway as another troubleshooting technique.

Joe

[NeuroJoe]

More data:

I found the USB pin schematic and used alligator clips to apply 5V regulated power over the 1st and 4th pins. Measured 4.98V on the multimeter, spark power light came on, but the sketch still would not run. Unplugged the alligator clips, hooked up the USB cable, and the sketch ran fine.  It's almost as if the sketch isn't being stored in the spark's memory, but is being uploaded every time it's hooked up to the computer via USB (even though I'm not hitting the upload button in the Digispark Arduino IDE after the first time I uploaded it, I'm just plugging in the USB cable to power it).

[NeuroJoe]

So Erik figured it out for me after looking at the sketch for 0.1seconds  You can't use the "Digikeyboard" call to act as a pseduo serial monitor if the spark isn't connected to USB. Which of course makes sense, but since I'm used to working with the regular Arduino IDE environment, and the serial monitor function doesn't balk this way, I didn't even think about it.

Joe

[exeng]

Ah yes software... That which breathes life into otherwise inanimate objects (or doesn't). Good catch Erik. I guess the key word was "appear" in the statement "...sketch doesn't appear to be running". Lesson learned.