my second raspberry has just passed away

A Former User

@spllg said in my second raspberry has just passed away:

the 3rd rpi has just passed away

version of them? and post failure which leds do what, is it the same for all of them? (edit: and how are they powered and conneted to the duet?)

spllg

@bearer Raspberry Pi 4 Modell B; 4 GB, ARM-Cortex-A72 4 x, 1,50 GHz, 4 GB RAM, WLAN-ac, Bluetooth 5, LAN, 4 x USB, 2 x Micro-HDMI

when powering up the red led is switched on. than the green led flashes a few times and nothing more happens.

when i put the sd-card into another rpi it boots fine.

yes, all the rpis passed away the same way - print stopped, rpi does not respond not even to a ping request and does no longer boot up.

the rpi is powered from an original rpi psu, the duet is 5v powered via the ribbon cable (5v->sbc and sbc->5v both closed as instructed by dc42).

spllg

@CaLviNx as it is the 3rd rpi demised in conjunction with my duet3 6hc) while 2 other rpis (not connected to a duet board) live for years now, i feel the duet is somewhat responsible for the deaths.

A Former User

@spllg said in my second raspberry has just passed away:

the rpi is powered from an original rpi psu, the duet is 5v powered via the ribbon cable (5v->sbc and sbc->5v both closed as instructed by dc42).

so in short the Pi and the Duet are always powered on at the same time? that was mostly what I was after.

understandably frustrating as those things aren't exactly cheap; is there anything else connected to the Pi and have you tried alternative boot medias to the SD card post failure? If you're not interested in spending time and effort on postmortem analysis thats understandable.

spllg

the rpi does not boot from another sd-card (which works fine in another rpi) and the rpi boots fine from the sd-card of the dead rpi.

there's an rpi display and an rpi camera connected to the rpi - unconnecting these devices and the duet ribbon cable does not change anything.

A Former User

@spllg said in my second raspberry has just passed away:

the rpi does not boot from another sd-card

i was thinking USB or PXE or something not an sd-card?

spllg

@bearer preparing a memorystick using dd. hopefully the rpi is able to boot from usb device.

A Former User

@spllg said in my second raspberry has just passed away:

@CaLviNx as it is the 3rd rpi demised in conjunction with my duet3 6hc) while 2 other rpis (not connected to a duet board) live for years now, i feel the duet is somewhat responsible for the deaths.

Horse Manure.....

As long as the duet is not sending an over-voltage to the Rpi (and you have said yourself the Duet is not the one sending the Rpi voltage) then I dont see how it is possible for the duet to kill the Rpi.

The logic is flawed i'm afraid.

spllg

@CaLviNx what do you mean "the logic is flawed"? please explain!

edit: the rpi has been working fine fine in conjunction with the duet for more than 4 months.

spllg

@bearer no, the rpi does not boot from usb-stick but i do not know if it would have done before. the only visible difference is that the green led stays on.

A Former User

i think calvinx is hinting at causation without correlation btw

anyways, no the pi4 needs an update to the boot eeprom to boot from anything other than the sd card, not sure if you can accomplish that easily without being able to boot from the sd card. maybe trying to recover the boot eeprom is worth a try, but if you say the green led does blink at boot then it sounds like it should be ok (it'd still be interesting to see if it was able to boot from another medium, however that requires changing or interfacing directly to the spi eeprom i think)

spllg

@bearer tried to follow the recovery section in https://www.raspberrypi.org/downloads/ but currently i do not have an empty sd-card. going to order one but i think unless the rpi can boot and operate from usb this will not solve my problem.

reconfigured my printer to operate without rpi - maybe this is an persistent solution although i'm going to lose some workaround.

still wondering what might be the reason for 3 dead rpis.

A Former User

@spllg you could image a card that is not empty, format it, put the recovery stuff on it, and restore the original content after attempting the recovery as an alternative to ordering a new card.

the pi4 can boot from usb, but weather or not you're able to make the seemingly damaged pi's boot from usb is another matter all together, its just a long shot to determine if the issue is the sd interface or something else.

does the screen show anything when you attempt to boot the dead pi, and is there any difference with or without an sd card?

dc42

I can think of a couple of situations in which the Duet cold send over-voltage to the Pi:

If you are powering a servo for the Duet +5V supply as well as the Pi. Servos inject current into the +5V rail when they decelerate. I've seen Vcc on a Duet 2 rise temporarily to 8V when driving a servo.
If you have a static discharge to +5V, which would typically be from an un-grounded stepper motor body or from the hot end.

spllg

@bearer currently my printer has to print (estimated completition tomorrow evening - late at least half a day). after having finished i will remove the rpi and follow the recovery instructions.

the display keeps dark. maybe i can obtain information via the serial interface .. tomorrow.

spllg

@dc42

no servo but i'm thinking of installing one - how to do this in a secure way?
none of the stepper bodies is grounded. should i ground the steppers?

generally: what additional precautions should i take? what documentation did i miss?

dc42

https://duet3d.dozuki.com/Wiki/Choosing_and_connecting_stepper_motors#Section_Connecting_stepper_motors

A Former User

@spllg said in my second raspberry has just passed away:

the display keeps dark

haven't tested how the pi4 reacts, but the previous will always display the 4 pixel interpolated rainbow thing before attempting to boot the kernel. it could be different if the boot eeprom is corrupted, but according to the internet the odds of that happening should be pretty slim.

but that you're not getting any output suggest the hdmi driver is done, or the cpu isn't even getting to the bootloader

spllg

@bearer can't get any info from the rpi - green led is unevenly blinking 3-4 times and than is switched off.

going tom buy a new rpi (€60). i will not 5v-power the duet from the rpi and see how long the rpi will be alive - hopefully longer than 4 month. if it will die again i will consider to try another board as i haven't got the time to mess around with hardware problems!

btw.: i remember the rpi freezed several times (days before) before it died.

A Former User

@spllg said in my second raspberry has just passed away:

@bearer can't get any info from the rpi - green led is unevenly blinking 3-4 times and than is switched off.

going tom buy a new rpi (€60). i will not 5v-power the duet from the rpi and see how long the rpi will be alive - hopefully longer than 4 month. if it will die again i will consider to try another board as i haven't got the time to mess around with hardware problems!

btw.: i remember the rpi freezed several times (days before) before it died.

Buy an Rpi3B+ from a reputable source, use the external 5v in (with a suitable amperage PSU) to provide system power to the Duet-3 which will then push the voltage TO the Rpi (with the correct jumpers being in place on the Duet-3) that combination is 100% working on multiple Duet-3's and has been for months for me with NO issues.

if you still cant work it out I would be willing to purchase the secondhand board from you as you are obviously unable to operate it properly.