Won't enter bootloader mode

I have a Plus 2 that I've had in a box for a while.  I tried to pull it out and fire it up, but I can't get the computer to recognize that it was even plugged in to the USB.  All that happens when I plug it in is the white power led comes on.  There's no difference if I hold down the button while I plug in the cable.  The blue led doesn't come on so I'm thinking that the bootloader isn't starting.

 

From all the posts I've read where people have this problem, they can at least get 2 leds on.  Is my netduino lost?

 

 

Hi spdygnlz,

With a Netduino mainboard, both the white LED and blue LED will turn on during power-up. If you hold the pushbutton during power-up the blue LED will remain on (since it's in bootloader mode...and therefore never starts an app).

If you hold the pushbutton while powering up your Netduino Plus 2, does it show up in Device Manager then?

Is it still in its original box? Was anything plugged into it? What were you using with it last time you used it?

If not...it may be that your Netduino got damaged somehow (or died, which is rare...but I'll never say never...).

Chris

I don't see anything in Device Manager when I plug it in while holding down the button.  

 

Last time I was using it, it was a little car that did some obstacle avoidance.  It was attached to an ultrasonic sensor and motor shield that drove a servo for steering and a motor for moving.  I had disconnected it the last time I put it away.  

 

I guess it must have been damaged somehow.  Is there any other advanced diagnostics I could run?  I do have a multimeter (but not very much electronics experience).  I just ordered myself a new netduino 3 board to replace it, but if I could resurrect this one it'd be great.

 

Thanks

Hi spdygnlz,

If the blue LED isn't turning on when you power it up, something has gotten fried on the board. Was your motor shield drawing motor current from the mainboard...or were you just using the Netduino for servo/motor signaling/speed control?

That said, there is a small chance that something else is afoot. The blue LED could have just burnt out.

If you measure the voltage between a GND header pin and the two sides of your LED, you should see 5V and GND (on the two different sides of the LED). If that is the case then the LED is burnt out and we may be able to help diagnose your board further. Or if you have a spare LED (a typical through-hole LED, with two legs), press one leg to each side of the blue LED (so that it's getting the same current source as the LED)--and see if the LED illuminates during power-up.

Chris

I see 5V on one side and only 3V on the other.

 

To be honest, I don't remember the configuration.  I want to say that the shield was drawing power from the mainboard.

Hi spdygnlz,

If you see 5V on one side of the LED and a lower voltage on the other, the LED could be damaged.

If you hold down the pushbutton while powering up the Netduino with your PC...do you see _anything_ pop up in Device Manager?

Chris

No, I've tried 2 different computers and neither register anything.  I don't even get an "Unknown device".