EHS8 problem. CDC_ACM driver fails with "failed to set dtr/rts" | Telit Cinterion IoT Developer Community
June 13, 2016 - 1:19pm, 13289 views
Hello, We are using EHS8 modem +gps module. We have found that sometimes data service and modem stop working. We have checked kernel output when that situation takes place and we get this error message:
521389.344607] cdc_acm 1-1.4.2.1:1.0: failed to set dtr/rts
The only way the recover gps / modem function is rebooting system.
We are using LInux with version:
Linux 3.19.0-25-generic #26~14.04.1-Ubuntu SMP Fri Jul 24 21:16:20 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
Hello,
Could you please share some more information?
What is the hardware that you are using with the module?
Would it be possible to provide the syslog with some more information? For now it's hard to say why this failure occurred.
So your impression is that the module stops working or there is a problem with communication with the PC? Have you tried to communicate with the module on another interface and execute some AT command - was it working?
Please also check the ATI1 command if possible to verify the firmware version.
Regards,
Bartłomiej
The hardware is an axiomtek capa841.- Intel atom 3845.
WE have the feeling that it tends to happen when radio coverage is very poor.
This is the output of de ATI1 command.
ATI1
Cinterion
EHS8
REVISION 03.001
A-REVISION 00.000.14
OK
pd[22958]: LCP terminated by peer
Jun 13 09:09:11 hostname pppd[22958]: Connect time 78.6 minutes.
Jun 13 09:09:11 hostname pppd[22958]: Sent 9207992 bytes, received 5159898 bytes.
Jun 13 09:09:12 hostname pppd[22958]: Modem hangup
Jun 13 09:09:12 hostname pppd[22958]: Connection terminated.
Jun 13 09:09:12 hostname pppd[22958]: Exit.
Jun 13 09:09:14 hostname ntpd[1754]: Deleting interface #10 ppp0, 10.40.243.218#123, interface stats: received=116, sent=122, dropped=0, active_time=4716 secs
Jun 13 09:09:14 hostname ntpd[1754]: 193.145.15.15 interface 10.40.243.218 -> (none)
Jun 13 09:09:14 hostname ntpd[1754]: 91.189.94.4 interface 10.40.243.218 -> (none)
Jun 13 09:09:14 hostname ntpd[1754]: peers refreshed
Jun 13 09:09:19 hostname pppd[31824]: pppd 2.4.5 started by root, uid 0
Jun 13 09:09:19 hostname pppd[31824]: Using interface ppp0
Jun 13 09:09:19 hostname pppd[31824]: Connect: ppp0 <--> /dev/ttyACM1
Jun 13 09:09:22 hostname pppd[31824]: local IP address 10.40.243.218
Jun 13 09:09:22 hostname pppd[31824]: remote IP address 10.40.243.218
Jun 13 09:09:22 hostname pppd[31824]: primary DNS address 80.58.61.250
Jun 13 09:09:22 hostname pppd[31824]: secondary DNS address 80.58.61.254
Jun 13 09:09:23 hostname ntpd[1754]: Listen normally on 11 ppp0 10.40.243.218 UDP 123
Jun 13 09:09:23 hostname ntpd[1754]: peers refreshed
Jun 13 09:09:23 hostname ntpd[1754]: new interface(s) found: waking up resolver
Jun 13 09:10:44 hostname dhcpd: Can't create new lease file: Permission denied
Jun 13 09:10:44 hostname dhcpd: DHCPREQUEST for 10.0.0.50 from ec:1f:72:bc:3d:7c (android-e9147931752dd933) via myAp
Jun 13 09:10:44 hostname dhcpd: DHCPACK on 10.0.0.50 to ec:1f:72:bc:3d:7c (android-e9147931752dd933) via myAp
Jun 13 09:15:33 hostname dhcpd: DHCPREQUEST for 10.0.0.50 from ec:1f:72:bc:3d:7c (android-e9147931752dd933) via myAp
Jun 13 09:15:33 hostname dhcpd: DHCPACK on 10.0.0.50 to ec:1f:72:bc:3d:7c (android-e9147931752dd933) via myAp
Jun 13 09:17:02 hostname CRON[8360]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Jun 13 09:20:21 hostname dhcpd: DHCPREQUEST for 10.0.0.50 from ec:1f:72:bc:3d:7c (android-e9147931752dd933) via myAp
Jun 13 09:20:21 hostname dhcpd: DHCPACK on 10.0.0.50 to ec:1f:72:bc:3d:7c (android-e9147931752dd933) via myAp
Jun 13 09:25:11 hostname dhcpd: DHCPREQUEST for 10.0.0.50 from ec:1f:72:bc:3d:7c (android-e9147931752dd933) via myAp
Jun 13 09:25:11 hostname dhcpd: DHCPACK on 10.0.0.50 to ec:1f:72:bc:3d:7c (android-e9147931752dd933) via myAp
Jun 13 09:28:15 hostname kernel: [ 8432.967935] cdc_acm 1-1.4.2.1:1.10: failed to set dtr/rts
Jun 13 09:28:20 hostname kernel: [ 8437.983027] cdc_acm 1-1.4.2.1:1.10: failed to set dtr/rts
Any feedback about it?
When that condition occurs, tty are not responsive to AT commands.
Hello,
The firmware is up to date. The log in fact also does not show anything strange before the "failed to set dtr/rts" message.
So to check if anything bad happens on the module some trace from the module would be needed - maybe there would be some information. You have also mentioned that you are using GPS. How are you using it - do you have any traces?
But on the other hand "failed to set dtr/rts" message could suggest that the problem is on the PC side not the module side - DTR and RTS lines are set by the PC, not by the module. You have written before "The only way the recover gps / modem function is rebooting system." - did you mean the module or the PC? If PC that could be the confirmation that PC is to blame here.
Regards,
Bartłomiej
Forcing a usb unbind, bind . It does not solve. I must power off and power on, again to get it working
I am using assisted gps, with active antenna.
So if only rebooting the PC helps it is quite meaningful - there must be some problem in the system or hardware interface. Maybe it would be good to test with some other Linux machine, check the system logs and look for information on some Linux forum.
Additionally you could try to connect the module to some other machine after this message happens to prove that it is still working.
Regards,
Bartłomiej