我有一个 USB 3g 调制解调器（华为 E303），在 Linux（Raspbian Jessie）下运行良好，作为一个独立的盒子原型，通过 WiFi 向手机和平板电脑（用于后台）提供网络内容。我已经配置了 udev，将其模式从插入更改为0x1f01插入0x1001，连接正确，拔下时干净地断开连接等。
今天我做了一个错误操作。我想可能是AT^U2DIAG=0。从那时起，它就卡在模式中0x1c05，被识别为 E173s（调制解调器开启）。并且无法将其切换回来。我试过拔下/插入（即使在 Windows 下，这也无济于事），我试过将 usb_modeswitch 切换回来，我试过AT^U2DIAG=1，结果却出现了+CME ERROR 50。
Mar 11 16:46:07 raspberrypi kernel: [ 421.900561] usb 1-1.2: new high-speed USB device number 6 using dwc_otg
Mar 11 16:46:07 raspberrypi rsyslogd-2007: action 'action 17' suspended, next retry is Fri Mar 11 16:46:37 2016 [try http://www.rsyslog.com/e/2007 ]
Mar 11 16:46:07 raspberrypi kernel: [ 422.001682] usb 1-1.2: New USB device found, idVendor=12d1, idProduct=1c05
Mar 11 16:46:07 raspberrypi kernel: [ 422.001710] usb 1-1.2: New USB device strings: Mfr=2, Product=1, SerialNumber=0
Mar 11 16:46:07 raspberrypi kernel: [ 422.001727] usb 1-1.2: Product: HUAWEI HiLink
Mar 11 16:46:07 raspberrypi kernel: [ 422.001742] usb 1-1.2: Manufacturer: HUAWEI
Mar 11 16:46:07 raspberrypi kernel: [ 422.003096] usb 1-1.2: bad CDC descriptors
Mar 11 16:46:07 raspberrypi kernel: [ 422.003441] usb 1-1.2: bad CDC descriptors
Mar 11 16:46:07 raspberrypi kernel: [ 422.007329] option 1-1.2:1.0: GSM modem (1-port) converter detected
Mar 11 16:46:07 raspberrypi kernel: [ 422.007840] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB0
Mar 11 16:46:07 raspberrypi kernel: [ 422.008900] option 1-1.2:1.1: GSM modem (1-port) converter detected
Mar 11 16:46:07 raspberrypi kernel: [ 422.009306] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB1
Mar 11 16:46:07 raspberrypi kernel: [ 422.010174] option 1-1.2:1.2: GSM modem (1-port) converter detected
Mar 11 16:46:07 raspberrypi kernel: [ 422.010687] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB2
如果我手动调用pon，聊天脚本会连接调制解调器，但调制解调器会立即断开连接：
Mar 11 16:31:21 raspberrypi pppd[6851]: Serial connection established.
Mar 11 16:31:21 raspberrypi pppd[6851]: Using interface ppp0
Mar 11 16:31:21 raspberrypi pppd[6851]: Connect: ppp0 <--> /dev/ttyUSB0
Mar 11 16:31:22 raspberrypi pppd[6851]: Remote message: Greetings!!
Mar 11 16:31:22 raspberrypi pppd[6851]: PAP authentication succeeded
Mar 11 16:31:22 raspberrypi pppd[6851]: Hangup (SIGHUP)
Mar 11 16:31:22 raspberrypi pppd[6851]: Modem hangup
Mar 11 16:31:22 raspberrypi pppd[6851]: Connection terminated.
Mar 11 16:31:22 raspberrypi avahi-daemon[418]: Withdrawing workstation service for ppp0.
如果您需要更多日志，请告诉我，我会将其粘贴到这里。