PC Engines apu2 experiences

[DaddyGo]

@vamike said in PC Engines apu2 experiences:

so you think "apu2 hardware generally doesn't work with serial and usb

hmmmm, ... no one assumed such a thing
just trying to figure out what is happening
while also having to "fumble" with ironic remarks

[stephenw10]

You can run usbconfig list to see info about the USB devices attached but it won't show the specific port only the bus.

But try just connecting anything, mouse, keyboard, data drive etc. Anything just to see if it also gets disconnected then the serial is attached.

Does it happen when you connect the serial cable if it isn't connected to the terminal client? That would almost certainly be the cable if so.

Steve

[VAMike]

@daddygo if you're trying to figure out what is happening the best thing to do is refrain from distracting commentary about what you think is "irrelevant"

@kevindd992002 if you got the two units at the same time I still wouldn't rule out wonky power supply as an issue. wall warts are notoriously unreliable, and I've seen >60% failure rates in the field (not DOA) from some batches in the past. those issues are complete PITA to debug because everything will work fine until the load reaches a certain point, then the PS can't keep up and weird things happen. much easier when they fail to the point that they melt, so the problem is obvious. trying different combinations of usb & serial is probably an easier place to start--throwing a thumb drive on with a serial console should work fine and is extremely well tested as a way to perform installs. if that doesn't work, definitely try a different serial cable and even a completely different serial source on the other end (e.g., try a different usb2serial converter on the machine you're using as a terminal). if it does work then you've narrowed down the source of the problem and it's neither serial nor usb generally, but that one specific usb device.

[DaddyGo]

@vamike said in PC Engines apu2 experiences:

the best thing to do is refrain from distracting commentary about what you think is "irrelevant"

hey buddy, leave it to those who know what they're doing, for example @stephenw10

[stephenw10]

Ok calm down! We are all trying to solve this problem.

Do not dismiss @VAMike. Review his old posts. You will see he knows what's what.

Steve

[DaddyGo]

@stephenw10 said in PC Engines apu2 experiences:

Ok calm down!

Okay, I understand, but I don't like it when someone arrives and immediately attacks...

@VAMike sorry bro, let's respect each other

+++edit: @stephenw10 by the way the best idea was the UPS ground loop

[kevindd992002]

@stephenw10 said in PC Engines apu2 experiences:

You can run usbconfig list to see info about the USB devices attached but it won't show the specific port only the bus.

But try just connecting anything, mouse, keyboard, data drive etc. Anything just to see if it also gets disconnected then the serial is attached.

Does it happen when you connect the serial cable if it isn't connected to the terminal client? That would almost certainly be the cable if so.

Steve

Ok, I did more tests and the results are more conclusive.

1. Both ports are labelled ugen0.2 when invoking usbconfig list which proves the point that that command lists only the bus.
2. Both ports are affected by the issue.
3. The issue only happens with the UPS USB device. I tried plugging in different devices (flash drives, keyboard, mouse, etc.) and all of them did not disconnect while the serial connection is opened.
4. When I connect the terminal, it disconnects the APC UPS and running the same command gives me this:

[2.5.2-RELEASE][root@pfSense.condo.arpa]/root: ugen0.2: <Unknown > at usbus0 (disconnected)
usbconfig list
ugen0.2: <Unknown > at usbus0 (disconnected)
ugen0.1: <0x1022 XHCI root HUB> at usbus0, cfg=0 md=HOST spd=SUPER (5.0Gbps) pwr=SAVE (0mA)
ugen1.1: <AMD EHCI root HUB> at usbus1, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=SAVE (0mA)
ugen1.2: <vendor 0x0438 product 0x7900> at usbus1, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=SAVE (100mA)

Look how it says "unknown" in ugen0.2. When this happens, unplugging and replugging the APC USB cable doesn't do anything.

It only happens when I connect the serial cable to the terminal client. If one end of the cable is connected to the APU2C4 but disconnected from the terminal client, no issue.

At this point, I would think the ground loop theory is making more sense to be the cause of the issue. What do you think? Can it still be the cable?

[DaddyGo]

@kevindd992002 said in PC Engines apu2 experiences:

What do you think? Can it still be the cable?

do you have a multimeter at your hand, with a diode tester (discontinuity measurement)?

+++edit:
the metal enclosures of UPS and APU stuff,- bringing them up to equipotential is not a bad idea

[kevindd992002]

@daddygo said in PC Engines apu2 experiences:

@kevindd992002 said in PC Engines apu2 experiences:

What do you think? Can it still be the cable?

do you have a multimeter at your hand, with a diode tester (discontinuity measurement)?

+++edit:
the metal enclosures of UPS and APU stuff,- bringing them up to equipotential is not a bad idea

I do. So you want me to see if there's low resistance between the APU's metal enclosure and UPS' ground point, correct? The UPS doesn't have a metal case because it's all plastic. It's an APC BR1500GI. So the ground points would be the screws and the third prong in the outlets themselves.

Do I test before and after the serial cable connection?

[DaddyGo]

@kevindd992002 said in PC Engines apu2 experiences:

The UPS doesn't have a metal case because it's all plastic.

I can already see the type (double insulated), the earthing is on the IEC13 connector(s) - the secondary circuit (after the inverter) is completely internally disconnected from primer

the middle leg of IEC13 is the ground, measure a resistance between this point and the APU metal housing

but you can also "ringing" the cable in question to see if there is a break somewhere

+++edit:
that reminds me, you say you have two of these boxes, how about testing the second one completely independently of the UPS on, say, on the kitchen table?

this would bring us closer to a solution

[VAMike]

@daddygo said in PC Engines apu2 experiences:

Okay, I understand, but I don't like it when someone arrives and immediately attacks...

you'll note that my first interaction with kevindd992002 in this thread dates from before you joined the forum...

[VAMike]

@kevindd992002 another possible low-cost thing to try would be to plug the ups cord and the apc into a powered usb hub, if you have one handy; that might isolate the connection a bit. those usb monitoring connections have historically played fast and loose with specs.

[kevindd992002]

@vamike said in PC Engines apu2 experiences:

@kevindd992002 another possible low-cost thing to try would be to plug the ups cord and the apc into a powered usb hub, if you have one handy; that might isolate the connection a bit. those usb monitoring connections have historically played fast and loose with specs.

What do you mean by ups cord and the apc? Are you referring to the same usb cable from the apc?

I actually thought of this too, adding a powered usb in between as I know the USB ports of the apu2c4 are problematic at best. I don't have one on hand but I can easily source for one, no problem.

[kevindd992002]

@vamike said in PC Engines apu2 experiences:

@daddygo said in PC Engines apu2 experiences:

Okay, I understand, but I don't like it when someone arrives and immediately attacks...

you'll note that my first interaction with kevindd992002 in this thread dates from before you joined the forum...

Yeah, I think @daddygo means well. Most of the times, language barrier is the culprit here.

[kevindd992002]

@daddygo said in PC Engines apu2 experiences:

@kevindd992002 said in PC Engines apu2 experiences:

The UPS doesn't have a metal case because it's all plastic.

I can already see the type (double insulated), the earthing is on the IEC13 connector(s) - the secondary circuit (after the inverter) is completely internally disconnected from primer

the middle leg of IEC13 is the ground, measure a resistance between this point and the APU metal housing

but you can also "ringing" the cable in question to see if there is a break somewhere

+++edit:
that reminds me, you say you have two of these boxes, how about testing the second one completely independently of the UPS on, say, on the kitchen table?

this would bring us closer to a solution

What do you mean by "ringing"?

I do have two pfsense boxes but one is remote from me so I can't use thst currently to test. I'll do your suggestions probably this week and post back.

[VAMike]

@kevindd992002 said in PC Engines apu2 experiences:

@vamike said in PC Engines apu2 experiences:

@kevindd992002 another possible low-cost thing to try would be to plug the ups cord and the apc into a powered usb hub, if you have one handy; that might isolate the connection a bit. those usb monitoring connections have historically played fast and loose with specs.

What do you mean by ups cord and the apc? Are you referring to the same usb cable from the apc?

sorry, too many three letter acronyms...plug the apc/ups into the hub and the hub into the apu. even if that works it's kind of fugly, but I don't know a good actual fix if the ups is doing something dodgy. you could try swapping that cable (but I wouldn't really expect it to help at this point), or using the serial option on the ups rather than the usb option (if both came in the box) but then you'd need a usb/serial adapter for the apc, or run your own second serial port to the headers on the board.

[stephenw10]

Does the UPS log anything when this happens? It looks like it removes itself as a device, though that seems unlikely.

[kevindd992002]

@vamike said in PC Engines apu2 experiences:

@kevindd992002 said in PC Engines apu2 experiences:

@vamike said in PC Engines apu2 experiences:

@kevindd992002 another possible low-cost thing to try would be to plug the ups cord and the apc into a powered usb hub, if you have one handy; that might isolate the connection a bit. those usb monitoring connections have historically played fast and loose with specs.

What do you mean by ups cord and the apc? Are you referring to the same usb cable from the apc?

sorry, too many three letter acronyms...plug the apc/ups into the hub and the hub into the apu. even if that works it's kind of fugly, but I don't know a good actual fix if the ups is doing something dodgy. you could try swapping that cable (but I wouldn't really expect it to help at this point), or using the serial option on the ups rather than the usb option (if both came in the box) but then you'd need a usb/serial adapter for the apc, or run your own second serial port to the headers on the board.

Ok, at this point it's really more of an isolation game. I'll see what I can do. Thanks for the suggestions.

[DaddyGo]

@kevindd992002 said in PC Engines apu2 experiences:

What do you mean by "ringing"?

sorry it's a technical term that's what I mean
(pin by pin you can measure the cable conductors)

https://www.youtube.com/watch?v=fLvQsHZr5NQ

BTW:

Thanks for the above comment - I certainly appreciate!!! "Yeah, I think daddygo means well.", you are right, English is not my mother language, I also speak Hungarian and Portuguese...

I finished the conversation with the "buddy", I approached him, but he remained dismissive!
(he must have woken up in the wrong place and I'm his target,
(but it certainly defines his mentality))

Some people are angry and some are calm

[kevindd992002]

@stephenw10 said in PC Engines apu2 experiences:

Does the UPS log anything when this happens? It looks like it removes itself as a device, though that seems unlikely.

I don't know where to check the UPS logs since it's a consumer UPS so the only software it has is for Windows.