Raspbery Pi 3B+ the USB ports don't work, and ethernet does not work
December 21, 2022, 07:20
Said cam is then probably faulty and would blow other pcs.
Now... how to fix this
But the cam is ok I plug it in to my old laptop and cam it works
Then something mustve happened in between...
How do I fix it 🤔
Long shot, but did you try to measure without sd card, ie without booting ?
On a Raspberry PI 3B+, it's simple to turn power on its four USB ports off and on. Simply write a "0" to /sys/devices/platform/soc/3f980000. usb/buspower to turn power off and a "1" to turn power on.
I remove the sd card still nothing
Try what i just sent, if you can ssh into it
Yes I can ssh
But wait, you said no ethernet either
That wont do then...
What is shown in lsusb and lspci ?
Please preferably paste as text or a screenshot atleast . . .
But wifi work
Mhm, atleast something 🙂
Thing is, pi3 schems are not public...
O
But sometimes ther is the 5v on usb
Yee... looks like ocp switch issue... give me a minute or two
Ok
Are you booted and in via ssh?
dmesg | grep current
Ya I am trying to find the ip of the ip
Mhm
I need to find the sd card with the wifi login in I will probably how to continue this tomorrow
just change it
if you are running raspbian
No
Ok 1 sec
both USB and ETH are connected through single chip - LAN9514
so does compute module... let me find schems for CM, as those ARE available
Ok
...reduced
ffs
I got ssh
dmesg | grep current
It is dmesg than what is that line
pipe
|
How do I type that
just googled that for you . . .
O thx
I think I typed it in right but it no work
wdym
ye, no match.
that's working properly.
it might be LAN9514 dead
O is it possible to replace
which revision you have
black or silver cpu
Silver
it is BGA.
that single chip closest to usbðernet
do you know how to replace BGA?
That chip
yes
LAN7515, on older models it was LAN9514 which was QFN, easily replaceable
I think I might me able to replace it
there's no guarantee it is actually that chip tho.
pcie lanes between bcm and that chip may be dead, or any surrounding circuitry might be toast...
and sadly, without full schem, there's no way to tell 😦
But it might be a good start
tbh...
how much do you value your time?
you already spent several hours on this
pi availability should be™️ back to normal in few weeks
according to rpi foundation ...
O If the suply would be back that would be nice that I would just get rid of this one
ye
or use this one through wifi
since it works well, except usbð
Will the gpio still work
gpio is directly to BCM
so it should
O than I can use it as a emulator station
yep
no need to toss it just because usbð is dead
sure, no regular keyboard can be attached. But you can emulate via serial line for example
or gpio matrix
Is ther a way to get at lest one usb out of the gpio
nope
or ... hold on.
Ok
nearly impossible.
it would need realtime hardware
Ok thanks for your information
gpio pins are software controlled, only somewhat hardware-controlled pins are two PWM outputs used for audio (that can be piped to GPIO pins)
no help with USB tho
both HW and SW limitations...
Ok at lest now I have some good news that I still can use raspberry pi 2nd that raspberry pi will be coming back to normal supply and 3rd I made a new friend
quote:
While this might work with some low speed devices, it's a bad idea for two reasons:
While you might be able to reprogram GPIO pins to high impedance state, that would only work until you reboot. For the time from power on to the moment your scripts disable the pins, you have potential for overcurrent conditions between USB and GPIO. This might be solved by putting resistors between the two, which may in turn have significant effects on USB communication.
USB 2.0 uses high-frequency signals (about 0.5 GHz) and requires careful signal routing. GPIO pins aren't designed to run at such frequencies, so PCB traces attached to them don't respect routing constraints. As a result, USB signals will get all sorts of artefacts (spikes, reflections etc.) which will probably prevent USB 2.0 devices from working. The same may be true for wires you solder, if you're not careful.
EDIT: to clarify about USB voltage levels, USB 2.0 Specification, section 7.3.2 "Bus Timing/Electrical Characteristics" says that voltage on data pins driven HIGH must be between 2.8 and 3.6 V, which should be generally compatible with 3.3V voltage levels of GPIO.