New pi 3b+ acting wierd

[cchisholm]

I fried my old raspberry pi3 b with a stupid user trick (tried to push into a case with the SD card half in, brock in half and shorted something).
The new one seems to be acting a bit weird, but not sure if it's me. The behaviors are...

1) I can not read most of my SD cards. I did find one that I could read, but most will not. Just acts like the card is empty even though the cards can be read on my older P2 just find.

2) The power light (red led on the back close to the USB plug) comes on, but as soon as it starts reading the one SD card I can read, it goes out and stays out and I only get the green light blinking as activity happens.

3) The new board does not show a version, but is dated 2017 (so maybe just newer). The chip configuration appears much different.

Am I mistaken that the red light should stay on the entire time? It does on my p2. I can't test on my old p3, but could it be something changed on the p3 that would prevent it from reading SD cards that work fine on the p2?

[davidcoton]

What is connected to your Pi?

The red LED goes out when the voltage is low. What PSU are you using (voltage and current specification).
Do you have a screen connected? If so, do you see a lightning bolt icon at the same time as the red LED goes out?

The Pi3B+ needs fully updated software, preferably Raspbian Stretch. Older versions won't work and updating is difficult. The telltape sign is a flashing pattern on the red LED. Not all non-Raspbian systems are Pi3B+ compatible. If you have an SDCard with Raspbian Stretch, then in the older Pi do:

Code: Select all

sudo apt update
sudo apt full-upgrade

then try it in the Pi3B+ again.

[cchisholm]

The p/s is set to 5.04 v and can provide 3a (it's a buck with attached v-mtr). I have checked the voltage with my fluke and it's right on.

The original SD was Stretch but the new p3 won't read it. The p2 will.

I am gonna start from scratch and build a new card, but I really have my doubts about this think. This is, I think, my 6th pi and my second p3 and have never hand a hiccup until now.

[davidcoton]

Did you try updating the SDCard on the Pi2?

Did you check the PSU voltage at the Pi? You could be losing voltage on the supply cable.

[HawaiianPi]

The p/s is set to 5.04 v and can provide 3a (it's a buck with attached v-mtr). I have checked the voltage with my fluke and it's right on.

A multi-meter will not show fast transient voltage spikes or dips. If your power LED is turning off, your power supply is inadequate. It either has poor voltage regulation, or the power wire between the PSU and Pi has too much resistance. How is the PSU connected to the Pi?

If the power supply you are using is designed for charging phone batteries, it may have poor regulation (battery charging does not require precise voltage control). I have a 5V/2.4A charger that dips well below 5V at only a 1A load. It charges my phone fine (phones only need a little over 4.2V to charge), but it's a lousy Pi PSU.

[crchisholm]

How is the PSU connected to the Pi?

The power supply is 240w 24v . From there, it is converted to 5v through a buck converter. I scoped it and did not see any significant voltage drops. From the buck converter to the micro usb power plug is a 2 inch length of 22awg wire pair.

Three may be a power drop but if so, it does not cause the power light to go out on any pi except this one.

[HawaiianPi]

There may be a power drop but if so, it does not cause the power light to go out on any pi except this one.

Not as meaningful as you might think, since the 3B+ is the most power hungry model.

Try bump the voltage up a bit more. Up to 5.25V should be safe (USB 2.0 power spec is 5V +/- 5%, and I've run my Pi3 at 5.25V).

From the buck converter to the micro usb power plug is a 2 inch length of 22awg wire pair.

Where did you get the micro USB plug (most are only rated to 1.8A)?

[cchisholm]

I will try bumping the voltage up to 5.25 and see how that effects things.

I have tried to find where I got the micro USB plug but at this point, I can't remember. That raises the question: why, if there was a problem with that plug, would it work (along with everything else i've outlined) for the past year or so with my previous rp 3 version 2. That board worked flawlessly until I got into too big a hurry and broke the SD card causing a short.

I just ordered the following....
https://www.amazon.com/gp/product/B00MA ... UTF8&psc=1

[cchisholm]

I have two older versions of pi

• 1) Pi2 B v1.1 dated 2014
  2) Pi2 B+ v1.2 dated 2014
  and the brand new
  3) pi3 B+ dated 2017

My neighbor who is also a Pi enthusiast loaned me a p/s that he uses on his pi3 B+ (BTW, he is as baffled by this as I am and insists that the SD card reader is bad.... if he is right, I need to return this (amazon) and get another)

Results: The power light stays on with all three boards. Board 1 and 2 can boot and run from my testing SD card. When they are powered up, the red light is solid and the green light flickers, and I can VNC into the board, using a wifi dongle, with no issue.

On new board 3, the green light comes on, does not flicker and I can not attach to it using VNC or ping it.

So if power is not the issue and if two older version can read the same SD card, what other issue can prevent the new P3 from booting.

the command as they came across above...

sudo apt update
sudo apt full-upgrade

...will not run. I did successfully run ...

Code: Select all

sudo apt-get update 
sudo apt-get upgrade

...so might be something got stripped in the message.

Have I left something untried?

[davidcoton]

the command as they came across above...

sudo apt update
sudo apt full-upgrade

...will not run. I did successfully run ...

Code: Select all

sudo apt-get update 
sudo apt-get upgrade

...so might be something got stripped in the message.

Have I left something untried?

The commands as listed seem to be correct (see man apt).
What errors do you get? Please quote them exactly.

[cchisholm]

with both I get....
sudo: apt: command not found

I think the problem was how old the version of Debian was. 7.6 found another SD with 9.x on it and the commands ran fine. I am currently building another 8gb with the most recent NOOBS.

Could the size of these SD cards be a problem? I use 8, 16, and 32gb cards. I have found a few 32's that seem to have issues. What I have been trying today, though, are mostly 8's

Charlie

[HawaiianPi]

The 3B+ needs newer firmware and a new kernel to support the new hardware, so the older cards not booting is expected.

Older versions of Raspbian Stretch can be updated to work with the Pi 3B+ model, but older releases like Jessie and Wheezy are not compatible. Other operating systems like Ubuntu will have to be updated for 3B+ compatibility by their developers. So your best bet with the newer models (like the 3B+ and 3A+) is to stick with the most recent Raspbian Stretch images.

To fully update/upgrade an older Raspbian Stretch system, use either of these 2 commands.

sudo apt update && sudo apt full-upgrade -y

sudo apt-get update && sudo apt-get dist-upgrade -y

Either insures you have the latest stable firmware and kernel.

I'm not a fan of NOOBS, because it doesn't get updated with the Raspbian OS, so upgrading Raspbian on a NOOBS card is not enough to fix a boot problem (you have to manually download and upgrade NOOBS).

[cchisholm]

Ok, end result: The Pi is bad.
How I know: I borrowed a friends Pi 3 (same model as the one I am having issues with) and tried to boot from the SD card that I setup clean with Debian Stretch. It came up perfectly. Tried again in my Pi 3 and it just keeps rebooting over and over.

I will be returning to Amazon for a refund and look to another supplier (this one came from Element 14)

Thanks for the advice to all.

Charlie

[jamesh]

Ok, end result: The Pi is bad.
How I know: I borrowed a friends Pi 3 (same model as the one I am having issues with) and tried to boot from the SD card that I setup clean with Debian Stretch. It came up perfectly. Tried again in my Pi 3 and it just keeps rebooting over and over.

I will be returning to Amazon for a refund and look to another supplier (this one came from Element 14)

Thanks for the advice to all.

Charlie

They are (alomsot) all made in the same factory, so the end supplier is on the whole irrelevant. Does sound like its a duff one - rare, but can happen.