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USB device mode not working
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lonelywolve

02/10/2023, 6:29 PM
First, I know that the documentation said that a USB-A to USB-A cable is recommended. But I do not have such a cable, and I also do not have a laptop with USB-A. So I tried a few different USB-A to USB-C cables, two different laptops and also different USB-C ports on the laptops and also turned the USB-C plug just in case it would matter. But so far, rpiboot does not find the CM4 eMMC. I'm now start thinking the USB-A port on my TuringPi2 is not working. Has anyone an idea? Unfortunately the BMC doesn't tell me if it should work or not. It just says "ok" when switching the mode.
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_dhanos_

02/10/2023, 6:32 PM
Hi
USB-C to USB-A very rarely work for people
There are only a few times this worked for someone
This is mostly either because you'll need a specific type of cable and a controller on your laptop that supports it, but we haven't figured this out yet (what could work)
Then, did you follow the documentation on flashing?
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lonelywolve

02/10/2023, 6:38 PM
ok. So in that case, I can't flash my CM4s without disassembling them again. And I'm probably not the only one not having USB-A ports anymore 🙂 Yes, I followed the steps. There aren't that many of them, and basically its very similar to the procedure of the "official" IO board. I checked out rpiboot, compiled and started it. I switched mode to device for a node (tried both tpi and web-ui) and then powered on the node (most of the time via web-ui, as tpi always boots all of them). rpiboot says "Waiting for BCM2835/6/7/2711..." and nothing happens.
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_dhanos_

02/10/2023, 6:40 PM
Yes, you are not the only one who has this problem and I understand you, but then there's not this much we can help you with if you do not have the right cable or ports to flash the modules on Turing Pi 2.
Like I said, we (the community, but also the Team) have not figure out yet which C-to-A cables work, but you'd need a specific one anyway
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lonelywolve

02/10/2023, 6:41 PM
Do you know if port replicators, docking stations and such would work to convert from USB-C to USB-A?
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_dhanos_

02/10/2023, 6:42 PM
I can check. I'll be flashing CM4s today and I have this USB-C hub that gives you many ports including USB-A. I'll let you know later when I check this
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lonelywolve

02/10/2023, 6:43 PM
thanks.
otherwise I'll disassemble and use the IO board to flash them. I had no issues flashing one before with the IO board using a USB-C to Micro-USB cable.
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_dhanos_

02/10/2023, 6:46 PM
I understand. Maybe you have the right cable then because it really should not differ (the carrier board and the TPi2 just route USB to the module)
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lonelywolve

02/10/2023, 6:48 PM
good to know, but unfortunately micro-USB doesn't fit into USB-A. 🙂 But I have a USB-C to USB-A cable from the same brand. I'll do again some tests with that. Can you confirm that I did the correct steps as written above? An I assume there is no way to check if the USB-A port ist defective, right?
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_dhanos_

02/10/2023, 6:52 PM
One thing you might try is to not use Node 1 for flashing - I've heard people are having issues with Node 1 for fleshing and this is being investigated
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lonelywolve

02/10/2023, 6:52 PM
hmm... "Second stage boot server done" 🙂
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_dhanos_

02/10/2023, 6:52 PM
Sorry, what steps do you mean?
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lonelywolve

02/10/2023, 6:55 PM
ok, I'm one step further. I successfully ran rpiboot on node2. Connection is now: TPI2 ----(USBA-USBC)-----> USB-C Y splitter -----> MacBook Pro.
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_dhanos_

02/10/2023, 6:56 PM
Great to hear
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lonelywolve

02/10/2023, 6:57 PM
the splitter made it. Not sure why. It wouln'd be necessary, but I think the splitter does only "USB", no USB-C power, videosignal and such stuff.
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_dhanos_

02/10/2023, 6:57 PM
Which splitter do you have? Might help others
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lonelywolve

02/10/2023, 6:59 PM
let me check
and the USB-C to USB-A cable used between splitter and TPI2 is this: https://www.ikea.com/ch/en/p/lillhult-usb-a-auf-usb-c-dunkelgrau-70527602/
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_dhanos_

02/10/2023, 7:05 PM
Thank you!
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lonelywolve

02/10/2023, 7:38 PM
But me on the list of people having issues with node 1 for flashing
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_dhanos_

02/10/2023, 7:43 PM
Ok, thank you for letting us know
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lonelywolve

02/11/2023, 10:09 AM
The issue on Node1 I have is looping with "Failed to write correct length, returned 0" on rpiboot. I also had issues with other nodes, mostly that flashing stoped at 41% saying error writing. I eventually flashed the CM4 on the IO board (successfully), therefore I at least know the eMMC is ok. Anyway, thanks for your help @_dhanos_
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_dhanos_

02/11/2023, 11:09 AM
This is a bit odd. no one before have had issues like that (with other nodes)
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lonelywolve

02/11/2023, 12:35 PM
hmm... maybe it's just my "special" cable combination. I was able to flash one, but failed on a few others.
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lfelder

02/11/2023, 9:29 PM
Aren't the missing CC-Line Restistors the cause for not working solutions with USB-C to USB-A cables? If properly implemented, a USB-C port should only provide power and exchange data when it senses a device (device pulls down those lines via 5.1 kOhm resistors). Normaly, a USB-A to USB-C should be used this way around and not the other way (as the USB A Port is a host port and not a device port, as b types are or c could be). Therefore the A to C cable is missing the two resistors on the CC lines. I aassume that the reported cases, were a A to C cable worked, was with computers that "accepted" devices even if they did not sense them correctly. Also this should explain why the splitter worked. It would make sense, if the splitter has the resistors embedded and does not connect the cc lines to the devices (the resistance would be too low, if you connect two devices in parallel). A similar issue exists with the pitray cm4 carrier board. This just works with A to C cables (c port on the carrier board) and not with C to C cables, because it is missing the resistors.
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_dhanos_

02/11/2023, 9:31 PM
Interesting. Thank you. And yeah, maybe, but we don't have enough examples to draw any conclusion yet. Interesting about the C-C cable on the Waveshare board.
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uppe

03/05/2023, 6:34 PM
Can confirm here that USB-A to USB-C cables do not work on a MacBook (macOS 13.2) here either... gonna have to go buy a new cable tomorrow
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trickydee

03/06/2023, 12:30 AM
I have been successful with the following crazy combination (I didnt have a direct USB A to USB A cable to hand): Mac -> USB A to USB C adapter -> USB C M to F (USB C extender cable ) -> USB C to USB A Cable -> tpi2 The cable only works when used in the combination above, the reverse does not work.
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kathy.auteberry

03/06/2023, 11:43 AM
Needs more adapters, that is crazy
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uppe

03/06/2023, 12:46 PM
I tried some adapter daisychaining too but nothing worked for me. Gonna try on a different computer today before I go get yet another single use cable
No luck on Mac even using USB-A to USB-A.. had problems on Windows too, got "unrecognized USB device", but when I switched to Node 2 it worked immediately
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_dhanos_

03/06/2023, 5:08 PM
Yeah, Node 1 is being problematic on some boards
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uppe

03/06/2023, 5:16 PM
Mac works too, if you follow the same instructions as for Windows. Maybe the instructions need updating? I had to specify
-d msd
for it to work with RPi Imager
Seems troubling if it's a QA issue, if it works with some boards and some not
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BigErchie

03/07/2023, 1:31 PM
I have the same problem here with Node 1, all other nodes work. As @_dhanos_ mentioned, I think some boards are problematic with that node. I wonder if its software or hadrware based issue 🤔
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_dhanos_

03/07/2023, 1:32 PM
I already checked firmware sources and don't see a bug there
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BigErchie

03/07/2023, 1:33 PM
I was hoping it was software and would be fixed in a future update ☹️
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trickydee

03/08/2023, 11:47 PM
FWIW - I learned today not to have "balena etcher" running on my mac while booting a CM4 in device mode. https://discord.com/channels/754950670175436841/1083173912306790510
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