Mid print hang 3.4.0b2, duet3, sbc
-
@zakm0n It sounds a lot like the SPI communication is interrupted by external sources. You may want to try to move other cables away from the SBC cable, replace it with a shorter one (if possible), or reduce the SPI frequency in
/opt/dsf/conf/config.json.Duet software engineer
-
@chrishamm I tried lowering the SPI frequency to half it's default. The SBC cable is run underneath the duet, so it should be well protected. I'm still getting disconnects because of SPI interruptions.
-
@chrishamm So, I have the chassis of the printer bonded to the mains earth, and after running a grounding wire to the body of the berd air pump, I'm now able to get about 3 hours into a print, but I'm still getting disconnects somewhere around the 3.5-4 hour mark into a print. Any other grounding you might suggest to get rid of noise? The SBC cable is run underneath of the Duet 3 and there's not really any way to further isolate it from the wiring of the machine. I'm at a loss here, and I'm considering ditching the Duet3 for something else going forward, as my personal machines with Klipper have absolutely never had such an issue, even in much less ideal setups.
-
@zakm0n said in Mid print hang 3.4.0b2, duet3, sbc:
The SBC cable is run underneath of the Duet 3 and there's not really any way to further isolate it from the wiring of the machine.
Foil tape as shielding?
-
@phaedrux I could try that, but I'll have to re-route the cable from behind the board. Foil tape has a way of shorting out things, doesn't it? I just can't understand how I'm seemingly the only one to ever have this problem.
-
@zakm0n said in Mid print hang 3.4.0b2, duet3, sbc:
Foil tape has a way of shorting out things, doesn't it?
A layer of non-conductive tape on top? There are purpose made shielded ribbon cables as well.
@zakm0n said in Mid print hang 3.4.0b2, duet3, sbc:
I just can't understand how I'm seemingly the only one to ever have this problem.
There are maybe a few other cases of similar interference I can think of, but it's usually been with a Duex ribbon cable or Paneldue picking up some noise.
The fact you're getting an improvement by increasing the grounding is promising though.
-
@zakm0n I grab Vin and GND for the Pi's buck converter relatively close from the Duet's Vin power connector in order to minimise potential interference.
I've been printing A LOT in SBC mode (countless prints > 7h) and I have not observed any connection drops on my setup. Do you get CRC errors when you bend or slightly twist the ribbon cable? If yes, try replacing it - a bad cable is the most plausible reason for your connection drops.
-
@chrishamm The PI has an external wall wart currently. The ribbon cable isn't in a place where it can be moved easily, so that hasn't been something I can test. Adding the grounding strap to the Berd pump got me from 10 minutes to 4 hours though, so I'm thinking grounding and shielding is where I should be focusing.
-
@phaedrux So, I managed to get the ribbon cable wrapped in metal foil tape and successfully printed a 6 hour print yesterday. I tried starting a print today and only made 10 minutes. It's like all of the gains I made by grounding and such just disappeared. It seems like this time there were a bunch of rapid connects and disconnects in the console on my paneldue.
-
And just as a verification if you have the berd air completely off the prints sill consistently complete without issue?
