Working great until I add some more USB connections (Pi)
I have server running on a pi 3b+ with a usb hub (powered) connected to 2 printers and 2 logitech c270 cameras. Also have a 7 inch touch lcd connected. I have a couple of issues:
- All seems to be good except that on reboot it seems to swap usbs around and so I must remember to check the printers before sending prints to the wrong ones. Any way to fix this?
- Adding two more usb cables (either in hub or straight into pi), these are 5 meter cables with the electronics in apparently to work with the extra distance, seems to cause the server to sort of freeze - lcd does not respond, prints stop and no comms to printers. Reboot using the menu brings it all back so not completely frozen (from what I can remember). Only have another logitech webcam connected to the new cables at this point, still building the Prusa. Happens everytime. I am going to check the hub psu just in case but otherwise any ideas?
PIs are always quite sensible on usb signals and voltage drops, so having multiple devices can easily cause problems with it. The active hub should help here if it has enough power. Over ssh run
and see if oyu get undervoltage messages like this:
2428924.651708] rpi_firmware_get_throttled: 17 callbacks suppressed
[2428924.651714] Voltage normalised (0x00000000)
[2428932.971643] Voltage normalised (0x00000000)
[2428951.691594] Voltage normalised (0x00000000)
[2429163.851612] rpi_firmware_get_throttled: 18 callbacks suppressed
[2429163.851620] Under-voltage detected! (0x00050005)
[2429188.811617] Under-voltage detected! (0x00050005)
[2429199.211604] Under-voltage detected! (0x00050005)
[2429238.731794] rpi_firmware_get_throttled: 20 callbacks suppressed
[2429238.731801] Voltage normalised (0x00000000)
[2429247.051754] Voltage normalised (0x00000000)
[2429253.291636] Voltage normalised (0x00000000)
[2429471.691635] rpi_firmware_get_throttled: 16 callbacks suppressed
[2429471.691643] Under-voltage detected! (0x00050005)
[2429486.251660] Under-voltage detected! (0x00050005)
[2429515.371649] Under-voltage detected! (0x00050005)
[2429559.051712] rpi_firmware_get_throttled: 13 callbacks suppressed
I also get them without problems, but as some point linux will disable usb which I gladly do not reach.
Long cables are not officially allowed for usb I think, also I know often they work. Might also depend on isolation against external signals. Hard to say since you do not see where problems come from.
Try first without webcams. The logitech should support MJPG so not add much bandwidth on usb but the usb bandwidth is limited, so first printers and if they work add cam one by one and no net select HD resolution. Pi is not the best device regarding band width. All share same usb port I think.