Featured Articles
Announcing Pi
Technical Specifications
Raspberry Pi FAQs
Win a Pi
Raspberry Pi Wishlist
Actions
Forum Thread Details
  • Replies 3 replies
  • Subscribers 675 subscribers
  • Views 731 views
  • Users 0 members are here
Related

Pi fails to boot

Former Member

Hi,

 

I received my pi on Saturday, and immediately went about trying to get it booted. On inserting the memory card, it didn't seem to fit in level. The left corner was being held out slightly. I removed the card and had a look, and noticed the pin on the far left, for pin 8, was bent out of shape, and was no longer in contact with the memory card.

 

Assuming it was important I used a crochet hook, and magnifying glass to try to carefully bend it back into shape. However, the thin metal contact just snapped.

 

Anyone know if this pin is important? On wikipedia it says this pin is usually not connected.

 

In addition, the pi won't boot. The red light comes on, and the green light is on very slightly. I have read on other posts that the SD card might be at fault. Didn't really want to go about buying several other cards though, only to find that none of them will work because of the broken contact.

 

Anyone here know if the pin in question is needed? If so, what should I do? If I return it as faulty, will I be at the back of the queue again, and have to wait some months for a replacement? Can the SD reader part be replaced by a novice solderer?

 

Thanks in advance for any help you guys can give.

 

Al

  • Well, here's my SWAG (Scientific Wild-A**ed Guess) based on the RasPi schematics (available at RasPi Hardware Wiki http://elinux.org/Rpi_Hardware#Schematic_.2F_Layout) and the Wikipedia Secure Digital page, section "Transfer Modes" (http://en.wikipedia.org/wiki/Sd_card#Transfer_modes).

     

    According to the schematics and SD transfer modes, pin 8 is only used for ultra-high speed UHS-I and UHS-II SD cards with a 4 bit wide data bus.  Such a card should be labelled UHS-I or UHS-II.  According to my understanding of Wikipedia SD, normal Class 2-10 SD cards don't use pin 8 and should be OK.  This assumes that what you call pin 8 is the same as what the Wikipedia entry calls pin 8 -- check the photos.

     

    The fact that you get a slightly on green LED suggests that the SoC is indeed trying to read the SD card.  If it were a 4 bit wide data bus I would think the SoC would crash almost immediately, but I don't know what it would do then -- maybe try all over again after a brief delay?  If it's a UHS-I or II card it definitely won't work.  You could very easily have another problem, such as inadequate power, so check the RasPi Troubleshooting wiki (http://elinux.org/R-Pi_Troubleshooting) and the RasPi Hardware wiki, section "Power Supply Problems" (http://elinux.org/RPi_Hardware#Power_Supply_Problems).  You could also have a bad SD card or the partitions aren't set up correctly.

  • in reply to johnbeetem

    Thanks for your reply.

     

    Yes, the pin 8 on the Wiki page given is the one. The thinner contact. The card doesn't say it is a UHS card. It is a Transcend 16GB Class 10 one, which is on the "working" list.

     

    I have tried 3 usb leads, and 2 power adapters. I don't have a multimeter to test the on board voltage, but shall endevour to get one. I have reinstalled the partitions several times using automated installers from RaspBMC, and dd for the debian image. I have used both windows and ubuntu to make the card. After playing most of Saturday evening, I left the pi with everything unplugged overnight. I shall see if I can get another SD card tomorrow to try. Fingers crossed.

  • Alexander Sheldon wrote:

     

    Anyone here know if the pin in question is needed? If so, what should I do? If I return it as faulty, will I be at the back of the queue again, and have to wait some months for a replacement? Can the SD reader part be replaced by a novice solderer?

    I've read that the RasPi distributors keep spares in stock for replacing bad units.  If this is true, you shouldn't have to wait long.  Try customer service.  You shouldn't have to replace the SD card receptacle yourself when it was delivered defective.  Besides, the distributors need to know how many defective units are being made.