How NB-IoT module (SIM7000-C) work on Rasberry Pi and Ubuntu Server 18.04

最近study了一下NB-IoT，並且稍微筆記了一下如何實作。

不過可惜的是我手邊目前並沒有NB-IoT的Sim卡，所以使用normal SIM卡搭配SIM7000C這張module做了些練習。

以下是我的測試設備:

• Rasberry Pi 2B
• Waveshare SIM7000C NB-IoT HAT
• CHT(中華電信) normal SIM
• OS: Ubuntu Server 18.04

How to connect with CHT cell site via AT commands:

Connect to SIM7000C via USB-console:

$ sudo screen /dev/ttyUSB3 115200

Examine SIM7000C is ready to use

at

Check PIN status

at+cpin?

Ready: SIM is not pending for any password.

Configure APN(Access Point Name) automatically

at+cgdcont=1,”ip”,””

1: cid

ip: packet data protocol type 

“”: apn

Check signal

at+csq

+csq: rssi, ber

rssi:

0 -115 dBm or less

1 -111 dBm

2...30 -110... -54 dBm

31 -52 dBm or greater

99 not known or not detectable

ber:0...7 As RXQUAL values in the table in GSM 05.08 [20] subclause 7.2.4

Scan cell site:

It will take about 120 secs or more, and 46692 is CHT.

at+cops=?

+cops=?

(index,format,oper)

Index: Integer type: order number of operator in SIM preferred

Format: 3GPP MCC/MNC

MCC	MNC	ISP
466	11	中華電信 (CHT)
466	92	中華電信 (CHT)
466	93	台灣大哥大
466	97	台灣大哥大
466	99	台灣電信
466	03	遠傳電信
466	01	遠傳電信
466	88	遠傳電信
466	89	台灣之星
466	12	亞太電信
466	12	亞太電信

oper: String type(string should be included in quotation marks)

Number	Type
0	GSM
7	CAT-M1
9	NB-IoT

Connect to CHT cell site:

at+cops=1,2,”46692” at+cgatt? at+cpsi?

+cops=index,format,oper

Get APN

We need APN for connecting to the Internet.

It seems normal CHT SIM card is used internet as APN, and NB-IoT of CHT is internet.iot.

at+cgnapn

+cgnapn valid,APN

0: The network did not sent APN parameter to UE.In the case, is NULL.

1: The network sent APN parameter to UE.

Connect to the Internet

at+cstt=”internet”

+cstt APN,username,password

Initial mobile data network

at+ciicr

Check public IP address

at+cifsr

Test1: Ping testing 

at+cipping=”168.95.1.1”

Test2: TCP testing

at+cipstart=”tcp”,”ftp.isu.edu.tw”,21

+cipstart=mode,ip,port

Mode: tcp,udp

看到這裡相信很多人已經放棄了，不過請別氣餒其實有更簡單好用的方法唷！

Connect to the Internet via nmcli and mmcli

Issue: nmcli cannot manage interfaces

# nmcli c up id GSM

Error: Connection activation failed: No suitable device found for this connection.

Workaround:

# mv /usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf  /usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf_orig # touch /usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf # systemctl restart network-manager

Ensure that mmcli can recognize and scan cell site

# mmcli -m 0

--------------------------------   General  |     dbus path: /org/freedesktop/ModemManager1/Modem/0            |            device id: fa2d54b8e3ad72c95e99f28ba51b4ce48565684b   --------------------------------   Hardware |         manufacturer: QUALCOMM INCORPORATED            |                model: 0            |             revision: MPSS.JO.3.0.2.c3-00140-9607_LTEONLY_PACK-1  1 [Feb 01 2018 07:00:00]            |         h/w revision: 10000            |            supported: gsm-umts, lte            |              current: gsm-umts, lte            |         equipment id: 865233030789763   --------------------------------   System   |       device: /sys/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.3            |              drivers: option1, qmi_wwan            |               plugin: SimTech            |         primary port: cdc-wdm0            |                ports: ttyUSB0 (qcdm), ttyUSB2 (at), cdc-wdm0 (qmi), wwan0 (net),             |                       ttyUSB3 (at)   --------------------------------   Status   |         lock: sim-pin2            |       unlock retries: sim-pin (3), sim-pin2 (3), sim-puk (10), sim-puk2 (10)            |                state: registered            |          power state: on            |          access tech: lte            |       signal quality: 94% (recent)   --------------------------------   Modes    |     supported: allowed: 2g; preferred: none            |                       allowed: 4g; preferred: none            |                       allowed: 2g, 4g; preferred: 4g            |                       allowed: 2g, 4g; preferred: 2g            |              current: allowed: 2g, 4g; preferred: 4g   --------------------------------   Bands    |     supported: egsm, dcs, pcs, g850, eutran-1, eutran-3, eutran-5, eutran-8            |              current: egsm, dcs, pcs, g850, eutran-1, eutran-3, eutran-5, eutran-8   --------------------------------   IP       |     supported: ipv4, ipv6, ipv4v6   --------------------------------   3GPP     |         imei: 865233030789763            |          operator id: 46692            |        operator name: 466 92            |         registration: home   --------------------------------   3GPP EPS | ue mode of operation: csps-2   --------------------------------   SIM      |     dbus path: /org/freedesktop/ModemManager1/SIM/0

# mmcli -m 0 --3gpp-scan --timeout=120

---------------------   3GPP scan | networks: 46612 - 466 12 (lte, available)             |           46692 - 466 92 (lte, current)             |           46605 - 466 05 (gsm, forbidden)

Connect to the Internet with nmcli

# nmcli c add type gsm ifname "*" con-name GSM apn "internet"

Connection 'GSM' (e79462c8-d02d-4ae0-b3f4-a08db28087af) successfully added.

# nmcli c up id GSM

相信這個方法簡單了許多吧！不過了解一下底層的AT command如何運作也是相當不錯的機會啦！以下是AT command完整的說明文件： http://www.waveshare.net/w/upload/4/49/SIM7000_Series_AT_Command_Manual_V1.02.pdf

Appendix:

AT+CMNB Preferred selection between CAT-M and NB-IoT.

+cmnb: mode

1 LTE CAT-M

2 NB-IoT

3 CAT-M and NB-IoT

SIM7000C + pppd撥接上網

1. To remove modemmanager firstly, otherwise ppp0 connection will be terminated by it.

$ sudo apt remove modemmanager

2. To install ppp

$ sudo apt install ppp

3. Configured ppp script for adding some AT commands.

$ cd /etc/ppp $ vi gprs-connect-chat

TIMEOUT 15 ABORT "DELAYED" ABORT "BUSY" ABORT "ERROR" ABORT "NO DIALTONE" ABORT "NO CARRIER" TIMEOUT 40 '' \rat OK at+cstt=\"internet\" OK at+cgatt? OK at+cpsi? OK at+ciicr OK ATD*99***1# CONNECT

4.  Configured ppp dial-in configuration file:

$ cd /etc/ppp/peers $ vi gprsdial

/dev/ttyUSB3 115200 crtscts modem debug nodetach usepeerdns noipdefault defaultroute 0.0.0.0:0.0.0.0 connect '/usr/sbin/chat -s -v -f /etc/ppp/gprs-connect-chat'

5. Added “noauth” parameter in /etc/ppp/options
6. Plug-in SIM7000C.
7. To execute pppd call 

$ sudo pppd call gprsdial

root@Lawrence-ThinkPad-T420S:/etc/ppp/peers# pppd call gprsdial  timeout set to 15 seconds abort on (DELAYED) abort on (BUSY) abort on (ERROR) abort on (NO DIALTONE) abort on (NO CARRIER) timeout set to 40 seconds send (^Mat^M) expect (OK) ^M DST: 0^M ^M *PSUTTZ: 19/06/26,08:14:58","+32",0^M at^M^M OK  -- got it send (at+cstt=\"internet\"^M) expect (OK) ^M at+cstt="internet"^M^M OK  -- got it send (at+cgatt?^M) expect (OK) ^M at+cgatt?^M^M +CGATT: 1^M ^M OK  -- got it send (at+cpsi?^M) expect (OK) ^M at+cpsi?^M^M +CPSI: LTE NB-IOT,Online,466-92,0xC8C9,54027119,280,EUTRAN-BAND8,3640,0,0,-9,-59 ,-50,20^M ^M OK  -- got it send (at+ciicr^M) expect (OK) ^M at+ciicr^M^M OK  -- got it send (ATD*99***1#^M) expect (CONNECT) ^M ATD*99***1#^M^M CONNECT  -- got it Script /usr/sbin/chat -s -v -f /etc/ppp/gprs-connect-chat finished (pid 2813), status = 0x0 Serial connection established. using channel 12 Using interface ppp0 Connect: ppp0 <--> /dev/ttyUSB3 sent [LCP ConfReq id=0x1 ] rcvd [LCP ConfReq id=0x0 ] sent [LCP ConfNak id=0x0 ] rcvd [LCP ConfAck id=0x1 ] rcvd [LCP ConfReq id=0x1 ] sent [LCP ConfAck id=0x1 ] sent [LCP EchoReq id=0x0 magic=0x640f0536] sent [PAP AuthReq id=0x1 user="Lawrence-ThinkPad-T420S" password=] rcvd [LCP DiscReq id=0x2 magic=0xd41b8a15] rcvd [LCP EchoRep id=0x0 magic=0xd41b8a15 64 0f 05 36] rcvd [PAP AuthAck id=0x1 ""] PAP authentication succeeded sent [CCP ConfReq id=0x1 ] sent [IPCP ConfReq id=0x1 ] rcvd [LCP ProtRej id=0x3 80 fd 01 01 00 0f 1a 04 78 00 18 04 78 00 15 03 2f] Protocol-Reject for 'Compression Control Protocol' (0x80fd) received rcvd [IPCP ConfReq id=0x0] sent [IPCP ConfNak id=0x0 ] rcvd [IPCP ConfRej id=0x1 ] sent [IPCP ConfReq id=0x2 ] rcvd [IPCP ConfReq id=0x1] sent [IPCP ConfAck id=0x1] rcvd [IPCP ConfNak id=0x2 ] sent [IPCP ConfReq id=0x3 ] rcvd [IPCP ConfAck id=0x3 ] Could not determine remote IP address: defaulting to 10.64.64.64 not replacing default route to enp0s25 [10.101.47.1] local  IP address 10.169.25.71 remote IP address 10.64.64.64 primary   DNS address 168.95.1.1 secondary DNS address 168.95.192.1 Script /etc/ppp/ip-up started (pid 2824) Script /etc/ppp/ip-up finished (pid 2824), status = 0x0 $ ifconfig ppp0 ppp0: flags=4305  mtu 1500         inet 10.169.25.71  netmask 255.255.255.255  destination 10.64.64.64         ppp  txqueuelen 3  (Point-to-Point Protocol)         RX packets 9  bytes 382 (382.0 B)         RX errors 0  dropped 0 overruns 0  frame 0         TX packets 18  bytes 1385 (1.3 KB)         TX errors 0  dropped 0 overruns 0  carrier 0 collisions 0 $ ping 168.95.1.1 -I ppp0 -c 3 PING 168.95.1.1 (168.95.1.1) from 10.169.121.115 ppp0: 56(84) bytes of data. 64 bytes from 168.95.1.1: icmp_seq=1 ttl=248 time=292 ms 64 bytes from 168.95.1.1: icmp_seq=2 ttl=248 time=460 ms 64 bytes from 168.95.1.1: icmp_seq=3 ttl=248 time=267 ms --- 168.95.1.1 ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 2000ms rtt min/avg/max/mdev = 267.265/340.248/460.987/85.994 ms