# Using a Huawei E173 USB Modem for Calls (chan\_dongle) The **Huawei E173** is a USB 3G modem from Huawei that is compatible with the **chan\_dongle** module for Asterisk. By using this modem with chan\_dongle, you can configure Asterisk to make voice calls and send SMS messages over the GSM network, effectively turning the modem into a full-fledged GSM gateway. {% hint style="warning" %} Dongle modems can be unstable. They require reliable, stable power and a strong GSM signal. {% endhint %} ## Preparing the USB Modem 1. First, let’s see which USB devices are connected to the PC: ```php lsusb Bus 001 Device 002: ID 12d1:1001 Huawei Technologies Co., Ltd. E169/E620/E800 HSDPA Modem Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 003: ID 0e0f:0002 VMware, Inc. Virtual USB Hub Bus 002 Device 002: ID 0e0f:0003 VMware, Inc. Virtual Mouse Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub ``` We’re interested in the device **"12d1:1001 Huawei Technologies..."**. * **12d1** – the vendor ID. * **1001** – the product ID. For the modem to function properly, you need to switch it to **"1001"** (modem-only mode). 2. Next, search for device info using the vendor ID **"12d1"**: ``` dmesg | grep 12d1 [ 2.828272] usb 1-1: New USB device found, idVendor=12d1, idProduct=1001, bcdDevice= 0.00 ``` 3. Then check for info by the USB device number **"usb 1-1"**: ```php dmesg | grep 'usb 1-1' [ 2.262750] usb 1-1: new high-speed USB device number 2 using ehci-pci [ 2.828272] usb 1-1: New USB device found, idVendor=12d1, idProduct=1001, bcdDevice= 0.00 [ 2.828479] usb 1-1: New USB device strings: Mfr=3, Product=2, SerialNumber=0 [ 2.828641] usb 1-1: Product: HUAWEI Mobile [ 2.828754] usb 1-1: Manufacturer: HUAWEI Technology [ 2.856994] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB0 [ 2.861194] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB1 [ 2.864265] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB2 ``` We see the modem’s serial devices: **ttyUSB0, ttyUSB1, ttyUSB2**. {% hint style="info" %} If these devices appear, half the work is done. If they’re missing, the modem may be in a mode other than **1001**. The product ID can vary with different firmware versions. On some devices, modem-only mode may appear as **"140c"**. {% endhint %} ## Checking the Modem Settings ``` minicom -D /dev/ttyUSB0 ``` You’ll see something like: ``` Welcome to minicom 2.8 OPTIONS: I18n Compiled on Apr 26 2021, 18:06:16. Port /dev/ttyUSB0, 12:30:42 Press CTRL-A Z for help on special keys ``` You can now enter **AT** commands to manage and configure the modem. ## Example Commands * **AT^CARDLOCK?** – Checks SIM lock status and the remaining attempts to enter an unlock code. (The modem’s response: `CARDLOCK: A,B,0`. If A=2, modem is unlocked; A=1, locked — SimLock; A=3, you either used all 10 attempts or have a customized firmware. B is the remaining number of attempts, typically 10.) * **AT^CARDLOCK="NCK Code"** – Unlock the modem to work with all mobile operators (if you have the code). * **AT^CVOICE=?** – Checks the modem’s voice support state (0 means voice is enabled). * **AT^CVOICE=0** – Enables voice functions on the modem. * **AT^U2DIAG=0** – Switch the modem into **modem-only** mode. ## What to Verify? 1. Confirm the modem **supports voice** functions. 2. The modem must be in **"modem-only"** mode (ID **1001**). 3. If possible (and if you have a code), **unlock** the modem for use with any operator. ## chan\_dongle for Asterisk 1. In the MikoPBX web interface, go to **System → Customize System Files**. 2. Open **`/etc/asterisk/modules.conf`**. 3. Set the mode to **"Append to the end of the file"**. 4. Add: ``` load => chan_dongle.so ``` 5. Open **`/etc/asterisk/dongle.conf`** for editing. 6. Choose **"Replace Completely"**. 7. Paste the following configuration: ```php [general] interval=15 [defaults] context=public-direct-dial group=0 rxgain=0 txgain=0 autodeletesms=yes resetdongle=yes u2diag=-1 usecallingpres=yes callingpres=allowed_passed_screen disablesms=no language=en smsaspdu=yes mindtmfgap=45 mindtmfduration=80 mindtmfinterval=200 callwaiting=auto disable=no initstate=start dtmf=relax [dongle0] audio=/dev/ttyUSB1 data=/dev/ttyUSB2 ``` 8. Re-open **`/etc/asterisk/modules.conf`**. 9. Again choose **"Append to the end of the file"**. 10. Add contexts for **SMS** and **USSD** handling: ```php [dongle-incoming-ussd] exten => ussd,1,Noop(Incoming USSD: ${BASE64DECODE(${USSDBASE64})}) exten => ussd,n,Hangup() [dongle-incoming-sms] exten => sms,1,Noop(Incoming SMS from ${CALLERID(num)} ${BASE64_DECODE(${SMS_BASE64})}) exten => sms,n,Hangup() ``` 11. After configuring **dongle.conf**, you must **restart** your PBX. {% hint style="info" %} **Helpful resources:** * See the [dongle.conf file](https://github.com/haha8x/asterisk-chan-dongle-16/blob/master/etc/dongle.conf) for a description of configuration and options. * More details in [chan\_dongle documentation](https://asterisk-service.com/en_US/page/chan-dongle-use). {% endhint %} {% hint style="danger" %} * **dongle0** is an arbitrary name of the line. It will be used in the Dial command for outgoing calls. * **audio** and **data** are the TTY device paths discovered in the previous step. You may need to swap them if there’s no audio. {% endhint %} ## Configuring DID Each **dongle** requires a DID number for correct inbound call handling. 1. Enter the Asterisk console: ```bash asterisk -r ``` 2. List the dongle devices: ``` mikopbx*CLI> dongle show devices ID Group State RSSI Model Firmware IMEI IMSI Number dongle0 0 Free 12 E173 11.126.15.00.209 *** *** 79255283744 ``` 3. If the `Number` column is empty, run: ```bash dongle cmd dongle0 AT+CPBS="ON" dongle cmd dongle0 AT+CPBW=1,"79255283744",145 ``` {% hint style="warning" %} Replace **dongle0** with your line’s identifier, and **"79255283744"** with the SIM’s phone number. {% endhint %} Restart your PBX afterwards. ## Configuring an Inbound Route 1. In the web interface, go to **Call** **Routing → Incoming Routing**.

"Incoming routing" section

2. Create a new rule. In the DID field, specify the SIM’s phone number you set earlier:

DID Number field

## Configuring Outbound Routes 1. In **Call** **Routing → Providers**, create a new **SIP** account with: * **Name** – “Dongle0” (or any name) * **Host or IP** – **127.0.0.1** * **Account Type** – “Authentication by IP address, no password”

Provider Parameters

2. Copy the **Provider ID** from the browser address bar (e.g., **SIP-TRUNK-C4153448**).

Provider ID

3. In **Call** **Routing → Outbound Routing**, create a new rule for sending calls via the modem:

Outbound route

4. Go to **System → System file customization** and open **`/etc/asterisk/extensions.conf`**. Choose “**Add to end of file**” and add: ```php [SIP-TRUNK-C4153448-outgoing-custom] exten => _[0-9*#+]!,1,Set(DIAL_COMMAND=Dongle/dongle0/${number}) same => n,return ``` {% hint style="info" %} Replace **SIP-TRUNK-C4153448** and **dongle0** with your IDs. {% endhint %}

Code for the file "extensions.conf"