loldavid6
Posts: 6
Joined: Mon Dec 23, 2013 5:50 pm

Connected 5v to 3.3 GPIO

Tue Apr 08, 2014 7:05 pm

Hi,
I think that I have accidentally connected the DNC 5v pin to the 3.3v pin on the Raspberry Pi's GPIO.
All the freshly formatted and flashed NOOBS SD cards I insert into the Raspberry Pi become instantly corrupt and give me the error message;

Code: Select all

 sh: can't access tty; job control turned off 
I fear that I may have made a permanent hardware fault and that I will have to buy a new RasPi.

Any suggestions, help or advice are very welcomed.

Thanks in advance,
David Doyle

simplesi
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Location: Euxton, Lancashire, UK
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Re: Connected 5v to 3.3 GPIO

Wed Apr 09, 2014 10:31 am

Pins 1 and 2 being connected together 99% of time means dead Pi :(
Time for a new one :(

Simon
Seeking help with Scratch and I/O stuff for Primary age children
http://cymplecy.wordpress.com/ @cymplecy on twitter

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Burngate
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Re: Connected 5v to 3.3 GPIO

Wed Apr 09, 2014 10:45 am

If you really have connected 5v to 3v3, then your Pi is probably toast

Three things may have happened:
The 3v3 regulator will not have liked 5v up its output (to misquote corporal Jones)
It may have sunk enough current to 'blow' the polyfuse, but also, in the process, it may have died
The SoC will probably not have survived 5v on its power pins.

Are you sure the SD cards "become instantly corrupt"?
Since the Pi isn't running (we assume) it can't be reading, or more to the point writing to, the card, so it can't be corrupting the files on the card.
Of course it could be that 5v is now reaching the card, but that would destroy it rather than corrupt it.
If the Pi isn't running, no remote connection is possible

Have a look at the cards on another system before declaring them corrupt.
Wait a day for the poly-fuse to recover (if it's blown), then connect the Pi to HDMI monitor and power supply only, with a fresh NOOBS card, and see what happens

loldavid6
Posts: 6
Joined: Mon Dec 23, 2013 5:50 pm

Re: Connected 5v to 3.3 GPIO

Wed Apr 09, 2014 2:50 pm

Thanks Burngate,
I think that msy be what has hsppened because when i first discovered this problem, and the RasPi crashed, it was coming up with some error messages about my usb keyboard (which is certified to work with the Pi) and when i plugged all usb peripherals out it said that there was a 3 port USB hub connectec :?: .

Thanks again for your help.

suicidal_orange
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Joined: Sun Mar 16, 2014 10:56 am

Re: Connected 5v to 3.3 GPIO

Thu Apr 10, 2014 7:19 am

Not that it helps you in any way but there is a 3 port hub connected - the LAN9512 chip on the model B (the square chip behind the USB ports) splits the USB to the two ports and the ethernet controller :)

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jojopi
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Re: Connected 5v to 3.3 GPIO

Fri Apr 11, 2014 4:58 am

loldavid6 wrote:sh: can't access tty; job control turned off
This message is usually characteristic of booting in safe mode because GPIO1 is pulled low. If GPIO1 has been damaged, you can add "avoid_safe_mode=1" to config.txt, or upgrade to bleeding edge firmware where the feature is removed. However, I am unsure how to achieve either of these via NOOBS.

It is possible that the USB hub/LAN was also damaged, but the USB messages you describe actually sound normal for safe mode. Does anything happen when you press Enter?

loldavid6
Posts: 6
Joined: Mon Dec 23, 2013 5:50 pm

Re: Connected 5v to 3.3 GPIO

Fri Apr 11, 2014 8:08 am

I did actually put that line and a couple others into a "config.txt" file to change my display settings primarily but also to see if it woul help in any way, which of course it did not. I will have to go and see if i have misspelled anything in the file.

p.s. sorry for any spelling mistakes (I'm writing this on a tablet).

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