Jason Wee

Important changes to forums and questions

All forums and questions are now archived. To start a new conversation or read the latest updates go to forums.mbed.com.

11 years, 11 months ago.

HELP: MBED does not light up when plugged in.

Hey everyone,

The LED in the middle of my mbed board used to light up (like normal) when plugged into my laptop. However, recently it's been dead when I plug it into my laptop. I noticed that the only way to get my mbed to work is to connect it to my laptop before turning it on, and once I've done that, it lights up together when I start up my laptop. Can anyone please let me know what is happening? Again, if my laptop is already running and I connect the mbed to it, it doesn't work.

Thanks.

2 Answers

X M
11 years, 11 months ago.

Have you checked this ? https://mbed.org/cookbook/deadmbed

Yes I have, and they require me to contact support@mbed.org. I wanted to try getting immediate help from the forum if I could. Thanks anyway.

posted by Jason Wee 03 Nov 2013
Erik -
11 years, 11 months ago.

Have you verified if your USB port delivers power? For example by just measuring the relevant mbed pins with a multimeter.

I have not done so. May I know how do I do so? Which pin do I measure across? And is it going to be voltage or current? I have also tried my friend's mbed using the same port, and it worked for him. Thanks for your reply.

posted by Jason Wee 03 Nov 2013

Voltage between Ground and VU. But if your friends mbed does work that does make it unlikely.

I don't think so with your description, but can't hurt to try, the standard rescue of dead mbeds: Unplug it, hold the reset button, plug it in, keep holding the reset button. Does it now show up on your computer? Format the mbeds drive, and keep holding the reset button.

posted by Erik - 03 Nov 2013

I have tried that and tried it again but it did not work. My laptop does not even detect MBED for some reason. I think I must have accidentally fried it because one of my devices connected to it (LCD screen) seems to be broken too.

posted by Jason Wee 04 Nov 2013

I have tried that and tried it again but it did not work. My laptop does not even detect MBED for some reason. I think I must have accidentally fried it because one of my devices connected to it (LCD screen) seems to be broken too.

posted by Jason Wee 04 Nov 2013