Hello all

may be or not related to the original hotspot hang description I experienced a complete failure of the USB subsystem on the raspberry Pi 4, 4 GB RAM , raspberry Pi power supply, sometimes after 30 minutes, sometimes several hours after boot:The only way to get the USB devices back was a reboot.

I found two reports [RPi4 4GB] xHCI host controller not responding, assume dead , Issues since kernel got updated to 4.19.93 . Without solving the underlying problem both recommended to increase in /boot/config.txt the value of the parameter

Having done that I rebooted and started INDI/EKOS with an ASI294MC@USB 3.0 and FTDI USB Serial Device@USB 2.0 ports (no powered USB hub). Then I set the camera to 1x1 binning and started a video. Within the last 23 hours the devices remained alive and the command shows:under "full video load" instead of 0.81 ... 0.83V. I let my setup run for a further day but I assume that solved my issue.

Reasonably increasing the CPU voltage does no harm. May be you give it a try.

Kind regards, wildi

Update 2020-02-10: the video stream and hence the USB devices are still alive.

The hub uses the USB3 micro-B cable design, which is an awful design and has in the past been disconnected by cable snags during slewing. I am considering glueing it, but for the time being I have contained everything in a wooden box and velcro'd everything to avoid any movement.

@gilesco: Maybe a smaller USB hub with a true USB 3 B connector might be less of a head ache. I have this (for comparison): www.amazon.com/gp/product/B00SIQIV04, and this cable: www.amazon.com/gp/product/B07QBG249T. The powered hub is small! Only 3.5 x 2.25 x 1.25 inches with 7 ports (5 on one side, and two on the other). It sits nicely on the OTA rail, where I have the Pi4, PPB, and SSD in a stack. Anyway, just an idea to eliminate the headache of the micro-B... Cheers, Doug

@Wildi: I tried your suggestion, and FYI, it didn't help with the USB hotspot problem. It DID raise the voltage to the core though, and I think this might have benefits as you suggest. So thanks for the suggestion. While looking at web references, I saw the Pi4 can have it's arm_freq safely raised a bit too. The parameter for config.txt is arm_freq=1750. After reboot I get the same voltage as you reported (0.91-0.94) and the added arm frequency boost. Hard to tell precisely, but it appears the cost is only 1-2 degrees C on the core. I'm running cool anyway @42C in daytime, because I have a heat sync and fan. Nighttime should be even better.

An update on my USB3 Pi4-4GB config after SM 1.5 upgrade. I really like this new release, but I'm still having negative USB3/network interaction that I'd like to solve. I can use a Pi4 USB3 port, but only AFTER booting the Pi4 without a connected USB3 cable. A USB3 powered hub is brought up stable before the Pi4 is booted. Here's the odd part: After USB3 hub is up, and after Pi4 is booted, I must FIRST connect the hub's USB3 cable to a Pi4 USB2 port! I can then almost immediately move the USB3 cable from the USB2 port to a USB3 port and keep a stable infrastructure network working indefinitely. Very odd, but very consistent. If I try to boot with a USB3 cable connected to a USB3 port, I almost immediately lock up the infrastructure network VNC session, fail back to hotspot mode, and can't recover the infrastructure network until I remove the USB3 cable AND reboot the Pi4 after the Pi4 returns to the hotspot network (reboot via hotspot VNC session). After the reboot, the infrastructure network returns normal again. Rinse and repeat. UGG.

I've found a few complaints in the Raspberry forum related to Pi4 USB3 and 2.4Ghz wifi interference. As a test, I wrapped my USB3 cable in tinfoil. No difference. I have an isolated 3amp Pi4 PS. I power the USB3 hub from a 10amp PS via PPB before booting the Pi4. I've removed a USB3 SSD out of the config for now. It mounts, but will also freeze the infrastructure network either immediately, or within 30 seconds of mounting. I've got only one USB3 cable (from the powered hub) connected to the Pi4. Everything else is in the powered USB3 hub. Plenty of power to the hub. The cable from Pi4 to hub is a USB3 B to A cable. I'm not quite convinced that USB3 is stable on Pi4. The need to first connect to USB2, then move to USB3 is a strong hint....but of what? If the issue is power related, it's hard to imagine (PPB shows good voltage and low current draw). FWIW, the SSD hangs the network regardless of whether it's plugged into the powered hub or directly from the Pi4's USB3 port. So, it's out for now while I try to understand what's going on with the USB3 hub/Pi4 cable.

While I have a startup strategy that can be infrastructure network stable, it's definitely not ideal. I'd like to be able to boot and have access to the infrastructure network without having to move cables. I'd also like to use my SSD. I'm running out of ideas. Comments?

I've used my USB 3 ASI533MC camera and a USB3 hub without any issues on RPi4. I've connected the USB 2 devices directly to the RPi4, to the ASI camera ports and to the hub. I've disconnected them completely and plugged them back in, never a problem except for the AVX cable connecting to a USB / Serial Prolithic adapter, unplugging it requires a reboot to get it going again.

No issues here with SM OS 1.5.1 and USB3. I've connected two USB 3 cameras at the same time and connected to SM over hotspot.. no networking issue or performance degradation.

One thing to check, especially if the RPI4 is an older one, is that the USB-controller firmware is up to date. There have been significant improvements to power consumption, temperature and device compatibility. Install package rpi-eeprom-update if not already installed and run "sudo rpi-eeprom-update" and it should show something like:
I have beta network-bootloader installed, but the important part is the VL805 version. If the versions aren't up to date "sudo rpi-eeprom-update -a" should update them.

@Jpaana: THANK YOU!!! This is great info to have for keeping the firmware up-to-date. I looked and I am up-to-date (but not beta). How do I retrieve the beta, and is it worth it to have it?

Look at this link for how to change to beta track: www.raspberrypi.org/documentation/hardwa...errypi/booteeprom.md

my advice, go with critical updaates first, if problem persists, review changelogs for beta and switch to beta if something looks like it may apply to you.

Take care with this, be prepared to maybe have to use the recovery image if something bricks your Pi4.

Good evening
I am about to put me RBPi3 out to pasture... no updates here recently. So has this issue been positively resolved?

Thanks

Hi Mike, You need to read this post: www.indilib.org/forum/general/6576-pi4-u...erference.html#51297
In a nutshell, RF interference between USB3 and 2.4Ghz wireless can not be overcome. If you intend to use USB3, you need to consider either a hardwire (cabled) ethernet, 5Ghz wireless, or blind hotspot (no internet) mode. The other suggestions in this thread were interesting and helpful, but not sufficient. In my case, I went cabled ethernet and my Pi4-4GB has been rock solid ever since. Others have had good success with 5GHz wireless. Clear Skies, Doug