I’m trying to get PPP connection working consistently but I’m having trouble with UG96 module. Today I get connected with ppp hundred times approximately (I am doing poff, going to low power, then wake up using external interrupt and then doing pon, then sleep several seconds and then again poff, sleep etc), and then everything failed. The module didn’t answer on AT command in connect chatscript. I can see /dev/ttyACM0, so everything is ok, I tried to set VBUS_CTRL to ‘0’ and then to ‘1’, and USB gets disconnected, and then connected, I see /dev/ttyACM0-6, but when I try to connect with pon program I am not getting answer on AT? I tried manually to communicate with module throug minicom /dev/ttyACM0, 115200 8N1, but no answer… Do anybody know what is going wrong, do I have to upgrade firmware on Quectel UG96? Thanks for answers in advance.
Thanks for your inquiry in Quectel forum.
Have you try to reset the module to check whethe it can restore ? And also you can try to control do not let it enter into low power to confirm whether it is normal ? From your description, the module seems like enter into dump status, it is abnormal, it may need to catch debug log to check it. Thanks!
Thanks for your answer. How can I catch debug log, there is some kind of software? I’m using UMTS<E kit so I’m not having possibility to reset module when it is failing by using GPIO, but in final product we will have reset of UG96 off course.
Thanks for your answer. About the debug log tool, cannot share with you in forum, you can email to firstname.lastname@example.org to get it.
About about the reset module, you can power off the module, then power on module again to check it. Thanks!
Sometimes UG96 USB fails and then it always shows this log:
[67008.288791] usb 2-1.2: new low-speed USB device number 50 using ehci-platform
[67008.408782] usb 2-1.2: device descriptor read/64, error -32
[67008.628770] usb 2-1.2: device descriptor read/64, error -32
[67008.848659] usb 2-1.2: new low-speed USB device number 51 using ehci-platform
[67008.948665] usb 2-1.2: device descriptor read/64, error -32
[67009.168660] usb 2-1.2: device descriptor read/64, error -32
[67009.288936] usb 2-1-port2: attempt power cycle
[67009.948889] usb 2-1.2: new low-speed USB device number 52 using ehci-platform
[67010.398748] usb 2-1.2: device not accepting address 52, error -32
[67010.508751] usb 2-1.2: new low-speed USB device number 53 using ehci-platform
[67010.948735] usb 2-1.2: device not accepting address 53, error -32
[67010.953545] usb 2-1-port2: unable to enumerate USB device
PPP can’t be established because /dev/ttyACM0 is not there. And after hundreds of tries it is the same… What is reason for this? We are going to low power, and then after waking up we got output as above.
Please confirm whether you have follow up the user guide to modify the kernel code to enable USB auto suspend function. Thanks!
I know for this patch of cdc-acm driver. I removed that because we had problems when USB is inactive and we are not in low power mode. After several hours of ppp running without activity USB disconnects, so I think that was because autosuspend function. Should I need to add these lines anyway?
Please have a try. Thanks!