Metro M4 Grand Central - DOA?

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noofny
 
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Metro M4 Grand Central - DOA?

Post by noofny »

I received this board today but when I plug it into power I get nothing. I took a video showing using the same USB cable working with another board...

https://vimeo.com/595633398

Couldn't find anything specific on how to power this board, am I missing something or is it DOA?


Cheers

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adafruit_support_carter
 
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Re: Metro M4 Grand Central - DOA?

Post by adafruit_support_carter »

Need to turn this switch to ON:
gc_power.jpg
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Here's the general guide for the Grand Central M4:
https://learn.adafruit.com/adafruit-grand-central

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noofny
 
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Re: Metro M4 Grand Central - DOA?

Post by noofny »

Sorry @adafruit_support_carter but that's not a very good response...

- Please watch the video I kindly shared, as it shows me using only USB power and trying to switch to no avail
- Your doco actually states "There is also an on/off switch. This switch is only for the DC jack and does not affect powering via USB" - https://learn.adafruit.com/adafruit-gra ... al/pinouts
- The schematics seem to support this - https://cdn-learn.adafruit.com/assets/a ... 1547234817

Before you ask - the video also demonstrates the USB cable and source of power are fully functioning and yes I did try multiple known functioning cables.

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adafruit_support_carter
 
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Re: Metro M4 Grand Central - DOA?

Post by adafruit_support_carter »

Oh, yep. Sorry. You're correct. For the GC, the switch is for the DC jack.

Do you have a multimeter? This behavior is weird and seems to indicate the voltage regulator might be dead.

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noofny
 
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Re: Metro M4 Grand Central - DOA?

Post by noofny »

I do have an old multimeter. I'm not confident enough with it to diagnose a small board/circuit like this, else I would have already.

Happy to cooperate and be guided through the process though, if that helps?

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Re: Metro M4 Grand Central - DOA?

Post by adafruit_support_carter »

OK, should be a pretty easy measurement. Esp. since you have the version without headers. The pads are nice and exposed.

Plug the USB cable back in to power the Grand Central. Then make two measurements. Measure the voltage (1) on the 5V pin and (2) on the 3.3V pin. What do you get for each?
gc.jpg
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noofny
 
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Re: Metro M4 Grand Central - DOA?

Post by noofny »

Cool, thanks for the clear instructions. What I got was...

3v pin = 0.333v
5v pin = 0.0v

EDIT: also including measurements I took on the same pins+cable+source on another working M4...

3v pin = 3.30v
5v pin = 5.07v

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Re: Metro M4 Grand Central - DOA?

Post by adafruit_support_carter »

Thanks. Yah, looks like it's just not getting power for some reason. Let's replace it.

Send an email to [email protected] with a link to this thread and your order number and they can send you a replacement Grand Central.

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noofny
 
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Re: Metro M4 Grand Central - DOA?

Post by noofny »

Have done - thanks for your help.

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