Posted: Wed May 22, 2013 0:02 Post subject: Mobile Broadband - Novatel Mifi2372 on TP-Link MR3420
Hello,
I am new to this forum so please go easy on me. I have recently installed v24 PreSP2 [Beta] build 21061 on my MR3420 without any issues. My problems began when I tried connecting my Mifi2372. It is not in the supported list, but has the same Modem ID as the 2352 (which IS on the supported list) - 1410:7001. My understanding is that the modems are identical except the 2352 covers the European freqs while the 2372 covers those in NA.
The majority of the time I cannot get my 2372 to connect but on the odd occasion (usually after unplugging the modem and reconnecting), it somehow manages to connect. After pouring through similar forum posts, I believe it may be related to usb_modeswitch and the fact that it comes up in CDROM mode upon first connection? I have contacted Novatel to ask for an AT command that disables the CDROM mode, but I'm not going to hold my breath on that one. If they do respond, I'll be sure to post it in here.
Here is some output that I managed to grab on one of the rare occasions where the modem successfully connected to the 3G network. The odd thing is that it connected on /dev/usb/tts/0 however, as you'll see at the bottom of the output, comgt info -d /dev/usb/tts/0 came up empty but it found something at /dev/usb/tts/3. Does that make sense to anyone?
Thanks in advance for all your help,
Dan
Code:
root@DD-WRT:/tmp# root@DD-WRT:/tmp# cat comgt.out
Dialling with custom string:ATD*99#
root@DD-WRT:/tmp/ppp# dmesg | grep usb
<6>[ 10.130000] usbcore: registered new interface driver usbfs
<6>[ 10.130000] usbcore: registered new interface driver hub
<6>[ 10.140000] usbcore: registered new device driver usb
<6>[ 14.950000] usb 1-1: new high-speed USB device number 2 using ar71xx-ehci
<6>[ 20.210000] usbcore: registered new interface driver usbserial
<6>[ 20.210000] usbcore: registered new interface driver usbserial_generic
<6>[ 20.230000] usbserial: USB Serial Driver core
<6>[ 20.450000] usbcore: registered new interface driver option
<4>[ 20.700000] usb 1-1: usbfs: process 1009 (usb_modeswitch) did not claim in terface 0 before use
<6>[ 20.970000] usb 1-1: USB disconnect, device number 2
<6>[ 21.370000] usb 1-1: new high-speed USB device number 3 using ar71xx-ehci
<6>[ 21.540000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB0
<6>[ 21.560000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB1
<6>[ 21.570000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB2
<6>[ 21.590000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB3
<6>[ 21.600000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB4
<6>[ 21.610000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB5
<6>[ 543.070000] usb 1-1: USB disconnect, device number 3
<6>[ 573.390000] usbcore: registered new interface driver cdc_acm
<6>[ 573.550000] usbcore: registered new interface driver sierra
<6>[ 7328.670000] usb 1-1: new high-speed USB device number 4 using ar71xx-ehci
<4>[ 7336.230000] usb 1-1: usbfs: process 14098 (usb_modeswitch) did not claim i nterface 0 before use
<6>[ 7336.490000] usb 1-1: USB disconnect, device number 4
<6>[ 7336.900000] usb 1-1: new high-speed USB device number 5 using ar71xx-ehci
<6>[ 7337.080000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB0
<6>[ 7337.090000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB1
<6>[ 7337.100000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB2
<6>[ 7337.120000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB3
<6>[ 7337.130000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB4
<6>[ 7337.140000] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB5
Since I have already installed the latest code according to the dd-wrt homepage, I'm assuming you mean my router hardware? Does that mean I am completely out of luck with my current configuration? Any suggestions for a replacement that can take a USB modem (with a "CDROM"-like autorun feature) as a WAN gateway?
MR3420 has a very weak power supply to the USB port and here is a prime example of what happens when the 3G dongle draws more power than the USB port can deliver.
The voltage on the port will drop down to such a low level that the 3G dongle resets, therefore disappear from the bus then reappears again in initial (cd-rom) mode, gets switched again by usbmodeswitch where-after driver attaches and creates the ttyUSB devices.
You have to use a separately powered USB hub with this dongle.
Thank you LOM! That was exactly the insight and advice I was hoping to get. It makes a lot of sense since I'd noticed the modem inexplicably dropping even after it managed to connect successfully.
I will give that a shot when I get home from work this afternoon.
