MuntyScruntfundle
Posts: 233
Joined: Fri Oct 27, 2017 11:14 pm

Pi 4 power?

Wed Jan 15, 2020 7:08 pm

Hi there.

I have a bunch of pi3s which are all powered from pin 2 and 3 (I think) on the header, and I've just received a couple of 4s to try. I have buster flashed to a known good 32gb card, but I can't get either 4 to do anything.

I plug the power in, get a couple of tiny flashes from the green led, then nothing. I've just hooked them up via the hdmi to see what's going on, nothing.

Is there anything physically different about these things I should know about? I know the power requirement is slightly different, but I know I'm providing enough millis. Do I have to tell it I'm providing power to the header? Any card restrictions? I had assumed they'd run with the same stuff plugged in.

Any ideas?
Many thanks.

MuntyScruntfundle
Posts: 233
Joined: Fri Oct 27, 2017 11:14 pm

Re: Pi 4 power?

Wed Jan 15, 2020 7:19 pm

Correct pin numbers 4 and 6!

klricks
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Location: Grants Pass, OR, USA
Contact: Website

Re: Pi 4 power?

Wed Jan 15, 2020 7:22 pm

MuntyScruntfundle wrote:
Wed Jan 15, 2020 7:08 pm
Hi there.

I have a bunch of pi3s which are all powered from pin 2 and 3 (I think) on the header, and I've just received a couple of 4s to try. I have buster flashed to a known good 32gb card, but I can't get either 4 to do anything.

I plug the power in, get a couple of tiny flashes from the green led, then nothing. I've just hooked them up via the hdmi to see what's going on, nothing.

Is there anything physically different about these things I should know about? I know the power requirement is slightly different, but I know I'm providing enough millis. Do I have to tell it I'm providing power to the header? Any card restrictions? I had assumed they'd run with the same stuff plugged in.

Any ideas?
Many thanks.
If the RPI3 has 'Buster' installed then you need to update and upgrade the SD card then move it to the RPi4.

Code: Select all

sudo apt update
sudo apt upgrade
If not Buster then you will need to do a fresh install.
Regarding power through GPIO 2 or 4 & 6, the RPi3 and RPi4 should work the same. Note that there in no power input fuse on the RPi4 as was on earlier models.
Last edited by klricks on Wed Jan 15, 2020 7:28 pm, edited 1 time in total.
Unless specified otherwise my response is based on the latest and fully updated Raspbian Buster w/ Desktop OS.

drgeoff
Posts: 10086
Joined: Wed Jan 25, 2012 6:39 pm

Re: Pi 4 power?

Wed Jan 15, 2020 7:26 pm

MuntyScruntfundle wrote:
Wed Jan 15, 2020 7:08 pm
Do I have to tell it I'm providing power to the header? Any card restrictions? I had assumed they'd run with the same stuff plugged in.
No, no and yes.

Read the "not booting" sticky, especially the parts that are RPI4B specific.
Last edited by drgeoff on Wed Jan 15, 2020 7:29 pm, edited 1 time in total.

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Imperf3kt
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Location: Australia

Re: Pi 4 power?

Wed Jan 15, 2020 7:27 pm

There is no need to update and upgrade 'Raspbian Buster' as it was released when the Pi4 was - all versions of Buster will boot a Pi4.
Updating is a good idea though.
If you are running "Stretch" or earlier, then you must upgrade it to Buster.

This sounds like a HDMI issue, have you checked the not booting sticky found in the troubleshooting section?
55:55:44:44:4C
52:4C:52:42:41

MuntyScruntfundle
Posts: 233
Joined: Fri Oct 27, 2017 11:14 pm

Re: Pi 4 power?

Wed Jan 15, 2020 8:38 pm

Yeah, it's a buster image.
Yes I'd done the eprom fix, I should have said. It took longer on one than the other, which suggests to me one of them needed updating and one didn't. Not sure what that says.
I've just tried downloading the image from a different page on the Rasperry site, not from the main options. There's a page where you can select the Buster with suggested stuff and the basic, downloaded the basic from there, and I have better results coming from my little flashing green friend!

Haven't fully connected to it yet, but I think we've got around that problem. Why that other image didn't work I have no idea. But there we go.

Thanks for the responses, all good stuff to check.

MuntyScruntfundle
Posts: 233
Joined: Fri Oct 27, 2017 11:14 pm

Re: Pi 4 power?

Wed Jan 15, 2020 8:49 pm

Hmm, spoke a little too soon.

With HDMI connected to either port I get the 4 raspberries, a very brief flash of a white panel with a raspberry on it, then the display dies.

The disk light continues to flash away for a couple of seconds, so I'm pretty sure it's booting, but the monitor output is getting cut.

I haven't seen any posts on this, so now I'm stumped. Unless this is the boot problem, I'll try the prom again, but I doubt that will do much.

Any other ideas?
Thanks again.

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Imperf3kt
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Location: Australia

Re: Pi 4 power?

Wed Jan 15, 2020 8:57 pm

Nothing I'm aware of, sorry.
This would be the first time I've heard of that behaviour.
Which HDMI port are you using?
55:55:44:44:4C
52:4C:52:42:41

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FTrevorGowen
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Re: Pi 4 power?

Thu Jan 16, 2020 12:12 am

MuntyScruntfundle wrote:
Wed Jan 15, 2020 8:49 pm
Hmm, spoke a little too soon.
With HDMI connected to either port I get the 4 raspberries, a very brief flash of a white panel with a raspberry on it, then the display dies.
The disk light continues to flash away for a couple of seconds, so I'm pretty sure it's booting, but the monitor output is getting cut.
I haven't seen any posts on this, so now I'm stumped. Unless this is the boot problem, I'll try the prom again, but I doubt that will do much.
Any other ideas?
Thanks again.
IIRC, there are three stages and associated mechanisms within the boot process during which (processed) edid-data from the display via the HDMI connection is passed into and from which a display "setting" is generated. It could be that your display (what is it?) is using some peculiar or (literally) odd clock timings which cause the latter stage(s) to fail. Assuming you can enable SSH (via the dummy ssh text file mechanism**) and have a wired or wireless network connection (the latter can be setup by a similar method to SSH) can you login to the partially booted P4 and post the output of these tvservice commands which may give us some clues:

Code: Select all

tvservice -n
tvservice -m DMT
tvservice -m CEA
tvservice -s
Have you made any changes to the default /boot/config.txt and/or /boot/cmdline.txt?
Trev.
** Some info. here: https://www.raspberrypi.org/documentati ... /README.md
Still running Raspbian Jessie or Stretch on some older Pi's (an A, B1, B2, B+, P2B, 3xP0, P0W, 2xP3A+, P3B+, P3B, B+, A+ and a B2) but Buster on the P4B's. See: https://www.cpmspectrepi.uk/raspberry_pi/raspiidx.htm

X-Gen
Posts: 59
Joined: Fri Dec 06, 2019 12:08 pm

Re: Pi 4 power?

Thu Jan 16, 2020 1:03 am

I hope you've confirmed that the pins receive enough power?
The Pi 4 needs about 2,5 amps at 5V.

MuntyScruntfundle
Posts: 233
Joined: Fri Oct 27, 2017 11:14 pm

Re: Pi 4 power?

Thu Jan 16, 2020 1:14 pm

So, some progress was made.

A micro to standard HDMI converter arrived today so I can test with my standard monitor. YAY! An intro screen and some introductions.

So, I changed my password, selected the UK, entered my wifi password, was warned there might now be a big update, screen went black.......

Again it appears to boot, or at least go through some kind of loading task, then the red goes off, then a couple of small green flashes, red comes on, then nothing. No output at all.

There are pages and pages of people not being able to get a stable connection to these things, I haven't found this exact problem anywhere, which seems odd.

The pi3 could sometimes be a little awkward for first connection, but this is beyond naff. The eproms ('very very unlikely corrupt..' - my arse!), no video output, doesn't read some 32gb cards, won't power with standard USBc cables, updates and stops working. And the list seems to go on.

I've used just about every small board out there for one reason or another, the raspberry has always been my favourite, but this release isn't good. A delayed release date while they tested it might have been a good idea!

Does anyone know if there is a return and replace policy with them? These are going back and I don't want another 2 'off the shelf', I'd like replacements that work.

Technocolour
Posts: 67
Joined: Thu Jul 04, 2019 6:23 pm

Re: Pi 4 power?

Thu Jan 16, 2020 3:24 pm

Contact your seller for their return policy.

Have you tried SSHing the pi (as per below, to check for info) or setting the HDMI safe mode to see if you get any video out?

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