Testing scenarios

The following testing scenarios give detailed instructions for testing specific use cases. They list the required AT commands and the expected responses.

Some scenarios are generic and should work out of the box, while others require you to set up a server that you can test against.

See Building and running for instructions on how to build and run the Serial LTE modem application. Testing describes how to turn on the modem and conduct the tests.

Generic AT commands

Complete the following steps to test the functionality provided by the Generic AT commands:

  1. Retrieve the version of the serial LTE modem application.

    AT#XSLMVER
    #XSLMVER: "1.5"
    OK
  2. Read the current baud rate.

    AT#XSLMUART?
    #XSLMUART: 115200
    OK

    You can change the used baud rate with the corresponding set command, but note that LTE Link Monitor requires 115200 bps for communication.

  3. Retrieve a list of all supported proprietary AT commands.

    AT#XCLAC
    AT#XSLMVER
    AT#XSLEEP
    AT#XCLAC
    AT#XSOCKET
    AT#XSOCKETOPT
    AT#XBIND
    [...]
    OK
  4. Check the supported values for the sleep command, then put the kit in sleep mode.

    AT#XSLEEP=?
    #XSLEEP: (0,1,2)
    OK

    AT#XSLEEP=0 puts the kit in idle mode. You can exit idle by GPIO.

    Alternatively, you can use different modes for #XSLEEP:

    • AT#XSLEEP=1 puts the kit in sleep mode. You can wake it up by GPIO.

    • AT#XSLEEP=2 powers off UART. You can power on UART again by GPIO.

TCP/IP AT commands

The following sections show how to test the functionality provided by the TCP and UDP AT commands.

TCP client

  1. Establish and test a TCP connection:

    1. Check the available values for the XSOCKET command.

      AT#XSOCKET=?
      #XSOCKET: (0,1),(1,2),(0,1),<sec-tag>
      OK
    2. Open a TCP socket, read the information (handle, protocol, and role) about the open socket, and set the receive timeout of the open socket to 30 seconds.

      AT#XSOCKET=1,1,0
      #XSOCKET: 1,1,0,6
      OK
      
      AT#XSOCKET?
      #XSOCKET: 1,6,0
      OK
      
      AT#XSOCKETOPT=1,20,30
      OK
    3. Connect to a TCP server on a specified port. Replace example.com with the hostname or IPv4 address of a TCP server and 1234 with the corresponding port. Then read the connection status. 1 indicates that the connection is established.

       AT#XCONNECT="example.com",1234
       #XCONNECT: 1
       OK
      
       AT#XCONNECT?
       #XCONNECT: 1
       OK
    4. Send plain text data to the TCP server and retrieve the returned data.

      AT#XSEND="Test TCP"
      #XSEND: 8
      OK
      
      AT#XRECV
      PONG: 'Test TCP'
      #XRECV: 17
      OK
    5. Close the socket and confirm its state.

      AT#XSOCKET=0
      #XSOCKET: 0,"closed"
      OK
      
      AT#XSOCKET?
      #XSOCKET: 0
      OK
  2. If you do not have a TCP server to test with, you can use TCP commands to request and receive a response from an HTTP server, for example, www.google.com:

    1. Open a TCP socket and connect to the HTTP server on port 80.

      AT#XSOCKET=1,1,0
      #XSOCKET: 1,1,0,6
      OK
      
      AT#XCONNECT="google.com",80
      #XCONNECT: 1
      OK
    2. Send an HTTP request to the server in data mode.

      AT#XSEND
      OK
    3. Send the text below as a whole (for example, as a copy and paste from a text editor).

        HEAD / HTTP/1.1<CR><LF>
        Host: www.google.com:443<CR><LF>
        Connection: close<CR><LF>
        <CR><LF>
      
    4. Exit data mode.

      +++
      OK
      
    5. Receive the response from the server.

      AT#XRECV
      HTTP/1.1 200 OK
      Content-Type: text/html; charset=ISO-8859-1
      [...]
      #XRECV: 576
      OK
      
      AT#XRECV
      [...]
      Connection: close
      #XRECV:147
      OK
    6. Close the socket.

      AT#XSOCKET=0
      #XSOCKET: 0,"closed"
      OK
  3. Test a TCP client with TCP proxy service:

    1. Check the available values for the XTCPCLI command.

      AT#XTCPCLI=?
      #XTCPCLI: (0,1,2),<url>,<port>,<sec_tag>
      OK
    2. Create a TCP/TLS client and connect to a server. Replace example.com with the hostname or IPv4 address of a TCP server and 1234 with the corresponding port. Then read the information about the connection.

      AT#XTCPCLI=1,"example.com",1234
      #XTCPCLI: 2,"connected"
      OK
      
      AT#XTCPCLI?
      #XTCPCLI: 1,0
      OK
    3. Send plain text data to the TCP server and retrieve ten bytes of the returned data.

      AT#XTCPSEND="Test TCP"
      #XTCPSEND: 8
      OK
      
      AT#XTCPRECV=10
      PONG: b'Te
      #XTCPRECV: 10
      OK
    4. Disconnect and confirm the status of the connection. -1 indicates that no connection is open.

      AT#XTCPCLI=0
      OK
      
      AT#XTCPCLI?
      #XTCPCLI: -1
      OK
  4. Test a TCP client with TCP proxy service in data mode:

    1. Create a TCP/TLS client and connect to a server with data mode support. Replace *example.com* with the hostname or IPv4 address of a TCP server and *1234* with the corresponding port. Then read the information about the connection.

      AT#XTCPCLI=2,"example.com",1234
      #XTCPCLI: 1,"connected"
      OK
      
      AT#XTCPCLI?
      #XTCPCLI: 1,1
      OK
    2. Send plain text data to the TCP server and retrieve the returned data.

      Test data mode
      PONG: b'Test data mode\r\n'
    3. Disconnect from the server.

      AT#XTCPCLI=0
      #XTCPCLI: "disconnected"
      OK

UDP client

  1. Test a UDP client with connectionless UDP:

    1. Open a UDP socket and read the information (handle, protocol, and role) about the open socket.

      AT#XSOCKET=1,2,0
      #XSOCKET: 1,2,0,17
      OK
      AT#XSOCKET?
      #XSOCKET: 1,17,0
      OK
    2. Send plain text data to a UDP server on a specified port. Replace example.com with the hostname or IPv4 address of a UDP server and 1234 with the corresponding port. Then retrieve the returned data.

      AT#XSENDTO="example.com",1234,"Test UDP"
      #XSENDTO: 8
      OK
      AT#XRECVFROM
      PONG: Test UDP
      #XRECVFROM: 14
      OK
    3. Close the socket.

      AT#XSOCKET=0
      #XSOCKET: 0,"closed"
      OK
  2. Test a UDP client with connection-based UDP:

    1. Open a UDP socket and connect to a UDP server on a specified port. Replace example.com with the hostname or IPv4 address of a UDP server and 1234 with the corresponding port.

      AT#XSOCKET=1,2,0
      #XSOCKET: 1,2,0,17
      OK
      
      AT#XCONNECT="example.com",1234
      #XCONNECT: 1
      OK
    2. Send plain text data to the UDP server and retrieve the returned data.

      AT#XSEND="Test UDP"
      #XSEND: 8
      OK
      
      AT#XRECV
      PONG: Test UDP
      #XRECV: 14
      OK
    3. Close the socket.

      AT#XSOCKET=0
      #XSOCKET: 0,"closed"
      OK
  3. Test a connection-based UDP client with UDP proxy service:

    1. Check the available values for the XUDPCLI command.

      AT#XUDPCLI=?
      #XUDPCLI: (0,1,2),<url>,<port>,<sec_tag>
      OK
    2. Create a UDP client and connect to a server. Replace example.com with the hostname or IPv4 address of a UDP server and 1234 with the corresponding port.

      AT#XUDPCLI=1,"example.com",1234
      #XUDPCLI: 2,"connected"
      OK
    3. Send plain text data to the UDP server and check the returned data.

      AT#XUDPSEND="Test UDP"
      #XUDPSEND: 8
      OK
      #XUDPDATA: 14
      PONG: Test UDP
    4. Disconnect from the server.

      AT#XUDPCLI=0
      OK
  4. Test a connection-based UDP client with UDP proxy service in data mode:

    1. Create a UDP client and connect to a server with data mode support. Replace example.com with the hostname or IPv4 address of a UDP server and 1234 with the corresponding port. Then read the information about the connection.

      AT#XUDPCLI=2,"example.com",1234
      #XUDPCLI: 1,"connected"
      OK
      
      AT#XUDPCLI?
      #XUDPCLI: 1,1
      OK
    2. Send plain text data to the UDP server and retrieve the returned data.

      Test UDP by hostname
      PONG: Test UDP by hostname
    3. Disconnect from the server.

      AT#XUDPCLI=0
      #XUDPCLI: "disconnected"
      OK

TLS client

Before completing this test, you must update the CA certificate, the client certificate, and the private key to be used for the TLS connection in the modem. The credentials must use the security tag 16842755.

To store the credentials in the modem, use LTE Link Monitor. See Managing credentials in the LTE Link Monitor User Guide for instructions.

You must register the corresponding credentials on the server side.

  1. Establish and test a TLS connection:

    1. List the credentials that are stored in the modem with security tag 16842755.

      AT%CMNG=1,16842755
      %CMNG: 16842755,0,"0000000000000000000000000000000000000000000000000000000000000000"
      %CMNG: 16842755,1,"0101010101010101010101010101010101010101010101010101010101010101"
      %CMNG: 16842755,2,"0202020202020202020202020202020202020202020202020202020202020202"
      OK
    2. Open a TCP/TLS socket that uses the security tag 16842755 and connect to a TLS server on a specified port. Replace example.com with the hostname or IPv4 address of a TLS server and 1234 with the corresponding port.

      AT#XSOCKET=1,1,0,16842755
      #XSOCKET: 1,1,0,258
      OK
      
      AT#XCONNECT="example.com",1234
      #XCONNECT: 1
      OK
    3. Send plain text data to the TLS server and retrieve the returned data.

      AT#XSEND="Test TLS client"
      #XSEND: 15
      OK
      
      AT#XRECV
      PONG: b'Test TLS client'
      #XRECV: 24
      OK
    4. Close the socket.

      AT#XSOCKET=0
      #XSOCKET: 0,"closed"
      OK
  2. Test a TLS client with TCP proxy service:

    1. Create a TCP/TLS client and connect to a server. Replace example.com with the hostname or IPv4 address of a TLS server and 1234 with the corresponding port. Then read the information about the connection.

      AT#XTCPCLI=1,"example.com",1234
      #XTCPCLI: 2,"connected"
      OK
      
      AT#XTCPCLI?
      #XTCPCLI: 1,0
      OK
    2. Send plain text data to the TLS server and retrieve the returned data.

      AT#XTCPSEND="Test TLS client"
      #XTCPSEND: 15
      OK
      #XTCPDATA: 24
      
      AT#XTCPRECV
      PONG: b'Test TLS client'
      #XTCPRECV: 24
      OK
    3. Disconnect from the server.

      AT#XTCPCLI=0
      #XTCPCLI: "disconnected"
      OK

DTLS client

The DTLS client requires connection-based UDP to trigger the DTLS establishment.

Before completing this test, you must update the Pre-shared Key (PSK) and the PSK identity to be used for the TLS connection in the modem. The credentials must use the security tag 16842756.

To store the credentials in the modem, enter the following AT commands:

AT%CMNG=0,16842756,3,"6e7266393174657374"
AT%CMNG=0,16842756,4,"nrf91test"

You must register the same PSK and PSK identity on the server side.

  1. Establish and test a DTLS connection:

    1. List the credentials that are stored in the modem with security tag 16842755.

      AT%CMNG=1,16842756
      %CMNG: 16842756,3,"0303030303030303030303030303030303030303030303030303030303030303"
      %CMNG: 16842756,4,"0404040404040404040404040404040404040404040404040404040404040404"
      OK
    2. Open a TCP/DTLS socket that uses the security tag 16842756 and connect to a DTLS server on a specified port. Replace example.com with the hostname or IPv4 address of a DTLS server and 1234 with the corresponding port.

      AT#XSOCKET=1,2,0,16842756
      #XSOCKET: 1,2,0,273
      OK
      
      AT#XCONNECT="example.com",1234
      #XCONNECT: 1
      OK
    3. Send plain text data to the DTLS server and retrieve the returned data.

      AT#XSEND="Test DTLS client"
      #XSEND: 16
      OK
      
      AT#XRECV
      PONG: b'Test DTLS client'
      #XRECV: 25
      OK
    4. Close the socket.

      AT#XSOCKET=0
      #XSOCKET: 0,"closed"
      OK
  2. Test a DTLS client with UDP proxy service:

    1. Create a UDP/DTLS client and connect to a server. Replace example.com with the hostname or IPv4 address of a DTLS server and 1234 with the corresponding port. Then read the information about the connection.

      AT#XUDPCLI=1,"example.com",1234,16842756
      #XUDPCLI: 2,"connected"
      OK
    2. Disconnect from the server.

      AT#XUDPCLI=0
      OK

TCP server

To act as a TCP server, the nRF9160 DK must have a global private address. The radio network must be configured to route incoming IP packets to the nRF9160 DK.

To check if the setup is correct, use the AT+CGDCONT? command to check if the local IP address allocated by the network is a reserved private address of class A, B, or C (see Private addresses). If it is not, ping your nRF9160 DK from the destination server.

  1. Create a Python script client_tcp.py that acts as a TCP client. See the following sample code (make sure to use the correct IP address and port):

    import socket
    import time
    
    host_addr = '000.000.000.00'
    host_port = 1234
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect((host_addr, host_port))
    time.sleep(1)
    print("Sending: 'Hello, TCP#1!")
    s.send(b"Hello, TCP#1!")
    time.sleep(1)
    print("Sending: 'Hello, TCP#2!")
    s.send(b"Hello, TCP#2!")
    data = s.recv(1024)
    print(data)
    
    time.sleep(1)
    print("Sending: 'Hello, TCP#3!")
    s.send(b"Hello, TCP#3!")
    time.sleep(1)
    print("Sending: 'Hello, TCP#4!")
    s.send(b"Hello, TCP#4!")
    time.sleep(1)
    print("Sending: 'Hello, TCP#5!")
    s.send(b"Hello, TCP#5!")
    time.sleep(1)
    data = s.recv(1024)
    print(data)
    
    print("Closing connection")
    s.close()
    
  2. Establish and test a TCP connection:

    1. Open a TCP socket, bind it to the TCP port that you want to use, and start listening. Replace 1234 with the correct port number.

      AT#XSOCKET=1,1,1
      #XSOCKET: 2,1,1,6
      OK
      
      AT#XBIND=1234
      OK
      
      AT#XLISTEN
      OK
    2. Run the client_tcp.py script to start sending data to the server.

    3. Accept the connection from the client and start receiving and acknowledging the data.

      AT#XACCEPT
      #XACCEPT: connected with IP address
      #XACCEPT: 3
      OK
      
      AT#XRECV
      Hello, TCP#1!Hello, TCP#2!
      #XRECV: 26
      OK
      
      AT#XSEND="TCP1/2 received"
      #XSEND: 15
      OK
      
      AT#XRECV
      Hello, TCP#3!Hello, TCP#4!Hello, TCP#5!
      #XRECV: 39
      OK
      
      AT#XSEND="TCP3/4/5 received"
      #XSEND: 17
      OK
    4. Observe the output of the Python script:

      $ python client_tcp.py
      
      Sending: 'Hello, TCP#1!
      Sending: 'Hello, TCP#2!
      TCP1/2 received
      Sending: 'Hello, TCP#3!
      Sending: 'Hello, TCP#4!
      Sending: 'Hello, TCP#5!
      TCP3/4/5 received
      Closing connection
      
    5. Close the socket.

      AT#XSOCKET=0
      #XSOCKET: "closed"
      OK
  3. Test the TCP server with TCP proxy service:

    1. Check the available values for the XTCPSVR command and read the information about the current state.

      AT#XTCPSVR=?
      #XTCPSVR: (0,1,2),<port>,<sec_tag>
      OK
      
      AT#XTCPSVR?
      #XTCPSVR: -1,-1
      OK
    2. Create a TCP server and read the information about the current state. Replace 1234 with the correct port number.

      AT#XTCPSVR=1,1234
      #XTCPSVR: 2,"started"
      OK
      
      AT#XTCPSVR?
      #XTCPSVR: 1,-1,0
      OK
    3. Run the client_tcp.py script to start sending data to the server.

    4. Observe that the server accepts the connection from the client. Read the information about the current state again.

      #XTCPSVR: IP address connected
      #XTCPDATA: 13
      #XTCPDATA: 13
      
      AT#XTCPSVR?
      #XTCPSVR: 1,2,0
      OK
    5. Start receiving and acknowledging the data.

      AT#XTCPRECV
      Hello, TCP#1!Hello, TCP#2!
      #XTCPRECV: 26
      OK
      
      AT#XTCPSEND="TCP1/2 received"
      #XTCPSEND: 15
      OK
      #XTCPDATA: 13
      #XTCPDATA: 13
      #XTCPDATA: 13
      
      AT#XTCPSVR?
      #XTCPSVR: 1,2,0
      OK
      
      AT#XTCPRECV
      Hello, TCP#3!Hello, TCP#4!Hello, TCP#5!
      #XTCPRECV: 39
      OK
      
      AT#XTCPSEND=1,"TCP3/4/5 received"
      #XTCPSEND: 17
      OK
    6. Observe the output of the Python script:

      $ python client_tcp.py
      
      Sending: 'Hello, TCP#1!
      Sending: 'Hello, TCP#2!
      TCP1/2 received
      Sending: 'Hello, TCP#3!
      Sending: 'Hello, TCP#4!
      Sending: 'Hello, TCP#5!
      TCP3/4/5 received
      Closing connection
      
    7. Read the information about the current state.

      AT#XTCPSVR?
      #XTCPSVR: 1,2,0
      OK
    8. Stop the server.

      AT#XTCPSVR=0
      #XTCPSVR:-1,"stopped"
      OK
      
      AT#XTCPSVR?
      #XTCPSVR: -1,-1
      OK
  4. Test the TCP server with TCP proxy service in data mode:

    1. Create a TCP server and read the information about the current state. Replace 1234 with the correct port number.

      AT#XTCPSVR=2,1234
      #XTCPSVR: 1,"started"
      OK
      
      AT#XTCPSVR?
      #XTCPSVR: 1,-1,1
      OK
    2. Run the client_tcp.py script to start sending data to the server.

    3. Observe that the server accepts the connection from the client and starts receiving data. Acknowledge the received data.

      #XTCPSVR: IP address connected
      Hello, TCP#1!Hello, TCP#2!TCP1/2 received
      Hello, TCP#3!Hello, TCP#4!Hello, TCP#5!TCP3/4/5 received
    4. Observe the output of the Python script:

      $ python client_tcp.py
      
      Sending: 'Hello, TCP#1!
      Sending: 'Hello, TCP#2!
      TCP1/2 received
      Sending: 'Hello, TCP#3!
      Sending: 'Hello, TCP#4!
      Sending: 'Hello, TCP#5!
      TCP3/4/5 received
      Closing connection
      
    5. Stop the server.

      AT#XTCPSVR=0
      #XTCPSVR: -1,"stopped"
      OK

UDP server

To act as a UDP server, the nRF9160 DK must have a global private address. The radio network must be configured to route incoming IP packets to the nRF9160 DK.

To check if the setup is correct, use the AT+CGDCONT? command to check if the local IP address allocated by the network is a reserved private address of class A, B, or C (see Private addresses). If it is not, ping your nRF9160 DK from the destination server.

  1. Create a Python script client_udp.py that acts as a UDP client. See the following sample code (make sure to use the correct IP addresses and port):

    import socket
    import time
    
    host_addr = '000.000.000.00'
    host_port = 1234
    host = (host_addr, host_port)
    local_addr = '9.999.999.99'
    local_port = 1234
    local = (local_addr, local_port)
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    s.bind(local)
    print("Sending: 'Hello, UDP#1!")
    s.sendto("Hello, UDP#1!", host)
    time.sleep(1)
    print("Sending: 'Hello, UDP#2!")
    s.sendto("Hello, UDP#2!", host)
    data, address = s.recvfrom(1024)
    print(data)
    print(address)
    
    print("Sending: 'Hello, UDP#3!")
    s.sendto("Hello, UDP#3!", host)
    time.sleep(1)
    print("Sending: 'Hello, UDP#4!")
    s.sendto("Hello, UDP#4!", host)
    time.sleep(1)
    print("Sending: 'Hello, UDP#5!")
    s.sendto("Hello, UDP#5!", host)
    data, address = s.recvfrom(1024)
    print(data)
    print(address)
    
    print("Closing connection")
    s.close()
    
  2. Establish and test a UDP connection:

    1. Open a UDP socket and bind it to the UDP port that you want to use. Replace 1234 with the correct port number.

      AT#XSOCKET=1,2,1
      #XSOCKET: 2,2,1,17
      OK
      
      AT#XBIND=1234
      OK
    2. Run the client_udp.py script to start sending data to the server.

    3. Start receiving and acknowledging the data. Replace example.com with the hostname or IPv4 address of the UDP client and 1234 with the corresponding port.

      AT#XRECVFROM
      Hello, UDP#1!
      #XRECVFROM: 13
      OK
      
      AT#XRECVFROM
      Hello, UDP#2!
      #XRECVFROM: 13
      OK
      
      AT#XSENDTO="example.com",1234,"UDP1/2 received"
      #XSENDTO: 15
      OK
      
      AT#XRECVFROM
      Hello, UDP#3!
      #XRECVFROM: 13
      OK
      
      AT#XRECVFROM
      Hello, UDP#4!
      #XRECVFROM: 13
      OK
      
      AT#XRECVFROM
      Hello, UDP#5!
      #XRECVFROM: 13
      OK
      
      AT#XSENDTO="example.com",1234,"UDP3/4/5 received"
      #XSENDTO: 17
      OK

      Note that you will get an error message if a UDP packet is lost. For example, this error indicates that a packet is lost in the downlink to the nRF9160 DK:

      AT#XRECVFROM
      #XSOCKET: -60
      ERROR
    4. Observe the output of the Python script:

      $ python client_udp.py
      
      Sending: 'Hello, UDP#1!
      Sending: 'Hello, UDP#2!
      UDP1/2 received
      ('000.000.000.00', 1234)
      Sending: 'Hello, UDP#3!
      Sending: 'Hello, UDP#4!
      Sending: 'Hello, UDP#5!
      UDP3/4/5 received
      ('000.000.000.00', 1234)
      Closing connection
      
    5. Close the socket.

      AT#XSOCKET=0
      #XSOCKET: 0,"closed"
      OK
  3. Test the UDP server with UDP proxy service:

    1. Check the available values for the XUDPSVR command and create a UDP server. Replace 1234 with the correct port number.

      AT#XUDPSVR=?
      #XUDPSVR: (0,1,2),<port>,<sec_tag>
      OK
      
      AT#XUDPSVR=1,1234
      #XUDPSVR: 2,"started"
      OK
    2. Run the client_udp.py script to start sending data to the server.

    3. Observe that the server starts receiving data and acknowledge the data.

      #XUDPDATA: 13
      Hello, UDP#1!
      #XUDPDATA: 13
      Hello, UDP#2!
      
      AT#XUDPSEND="UDP1/2 received"
      #XUDPSEND: 15
      OK
      
      #XUDPDATA: 13
      Hello, UDP#3!
      #XUDPDATA: 13
      Hello, UDP#4!
      #XUDPDATA: 13
      Hello, UDP#5!
      
      AT#XUDPSEND="UDP3/4/5 received"
      #XUDPSEND: 17
      OK
    4. Observe the output of the Python script:

      $ python client_udp.py
      
      Sending: 'Hello, UDP#1!
      Sending: 'Hello, UDP#2!
      UDP1/2 received
      ('000.000.000.00', 1234)
      Sending: 'Hello, UDP#3!
      Sending: 'Hello, UDP#4!
      Sending: 'Hello, UDP#5!
      UDP3/4/5 received
      ('000.000.000.00', 1234)
      Closing connection
      
    5. Close the socket.

      AT#XUDPSVR=0
      #XUDPSVR: "stopped"
      OK
  4. Test the UDP server with UDP proxy service in data mode:

    1. Create a UDP server and read the information about the current state. Replace 1234 with the correct port number.

      AT#XUDPSVR=2,1234
      #XUDPSVR: 1,"started"
      OK
      
      AT#XUDPSVR?
      #XUDPSVR: 1,1
      OK
    2. Run the client_udp.py script to start sending data to the server.

    3. Observe that the server starts receiving data. Acknowledge the received data.

      Hello, UDP#1!Hello, UDP#2!UDP1/2 received
      Hello, UDP#3!Hello, UDP#4!Hello, UDP#5!UDP3/4/5 received
    4. Observe the output of the Python script:

      $ python client_udp.py
      
      Sending: 'Hello, UDP#1!
      Sending: 'Hello, UDP#2!
      UDP1/2 received
      ('000.000.000.00', 1234)
      Sending: 'Hello, UDP#3!
      Sending: 'Hello, UDP#4!
      Sending: 'Hello, UDP#5!
      UDP3/4/5 received
      ('000.000.000.00', 1234)
      Closing connection
      
    5. Stop the server.

      AT#XUDPSVR=0
      #XUDPSVR: "stopped"
      OK

TLS server

The TLS server role is currently not supported.

AT#XSOCKET=1,1,1,16842753
#XSOCKET: "(D)TLS Server not supported"
ERROR

AT#XTCPSVR=1,3443,16842753
#XTCPSVR: "TLS Server not supported"
ERROR

DTLS server

The DTLS server role is currently not supported (modem limitation).

AT#XSOCKET=1,2,1,16842755
#XSOCKET: "(D)TLS Server not supported"
ERROR

DNS lookup

  1. Look up the IP address for a hostname.

    AT#XGETADDRINFO="www.google.com"
    #XGETADDRINFO: "172.217.174.100"
    OK
    
    AT#XGETADDRINFO="ipv6.google.com"
    #XGETADDRINFO: "2404:6800:4006:80e::200e"
    OK
    
    AT#XGETADDRINFO="172.217.174.100"
    #XGETADDRINFO: "172.217.174.100"
    OK
    
    AT#XGETADDRINFO="2404:6800:4006:80e::200e"
    #XGETADDRINFO: "2404:6800:4006:80e::200e"
    OK

Socket options

After opening a client-role socket, you can configure various options.

  1. Check the available values for the XSOCKETOPT command.

    AT#XSOCKETOPT=?
    #XSOCKETOPT: (0,1),<name>,<value>
    OK
  2. Open a client socket.

    AT#XSOCKET=1,1,0
    #XSOCKET: 2,1,0,6
    OK
  3. Test to set and get socket options. Note that not all options are supported.

    AT#XSOCKETOPT=1,20,30
    OK
    
    AT#XSOCKETOPT=0,20
    ERROR  // to be investigated
    
    AT#XSOCKETOPT=0,2
    #XSOCKETOPT: "ignored"
    OK
    
    AT#XSOCKETOPT=1,2,1
    #XSOCKETOPT: "ignored"
    OK
    
    AT#XSOCKETOPT=0,61
    #XSOCKETOPT: "not supported"
    OK
    
    AT#XSOCKETOPT=1,61,30
    #XSOCKETOPT: "not supported"
    OK

ICMP AT commands

Complete the following steps to test the functionality provided by the ICMP AT commands:

  1. Ping a remote host, for example, www.google.com.

    AT#XPING="www.google.com",45,5000,5,1000
    OK
    #XPING: 0.637 seconds
    #XPING: 0.585 seconds
    #XPING: 0.598 seconds
    #XPING: 0.598 seconds
    #XPING: 0.599 seconds
    #XPING: average 0.603 seconds
    
    AT#XPING="ipv6.google.com",45,5000,5,1000
    OK
    #XPING: 0.140 seconds
    #XPING: 0.109 seconds
    #XPING: 0.113 seconds
    #XPING: 0.118 seconds
    #XPING: 0.112 seconds
    #XPING: average 0.118 seconds
  2. Ping a remote IP address, for example, 172.217.174.100.

    AT#XPING="172.217.174.100",45,5000,5,1000
    OK
    #XPING: 0.873 seconds
    #XPING: 0.576 seconds
    #XPING: 0.599 seconds
    #XPING: 0.623 seconds
    #XPING: 0.577 seconds
    #XPING: average 0.650 seconds

FTP AT commands

Note that these commands are available only if CONFIG_SLM_FTPC is defined. Before you test the FTP AT commands, check the setting of the CONFIG_FTP_CLIENT_KEEPALIVE_TIME option. By default, the FTP client library keeps the connection to the FTP server alive for 60 seconds, but you can change the duration or turn KEEPALIVE off by setting CONFIG_FTP_CLIENT_KEEPALIVE_TIME to 0.

The FTP client behavior depends on the FTP server that is used for testing. Complete the following steps to test the functionality provided by the FTP AT commands with two example servers:

  1. Test an FTP connection to “speedtest.tele2.net”.

    This server supports only anonymous login. Files must be uploaded to a given folder and will be deleted immediately. It is not possible to create, rename, or delete folders or rename files.

    1. Connect to the FTP server, check the status, and change the transfer mode. Then disconnect.

      AT#XFTP="open",,,"speedtest.tele2.net"
      220 (vsFTPd 3.0.3)
      200 Always in UTF8 mode.
      331 Please specify the password.
      230 Login successful.
      OK
      
      AT#XFTP="status"
      215 UNIX Type: L8
      211-FTP server status:
           Connected to ::ffff:202.238.218.44
           Logged in as ftp
           TYPE: ASCII
           No session bandwidth limit
           Session timeout in seconds is 300
           Control connection is plain text
           Data connections will be plain text
           At session startup, client count was 38
           vsFTPd 3.0.3 - secure, fast, stable
      211 End of status
      OK
      
      AT#XFTP="ascii"
      200 Switching to ASCII mode.
      OK
      
      AT#XFTP="binary"
      200 Switching to Binary mode.
      OK
      
      AT#XFTP="close"
      221 Goodbye.
      OK
    2. Connect to the FTP server and retrieve information about the existing files and folders.

      AT#XFTP="open",,,"speedtest.tele2.net"
      220 (vsFTPd 3.0.3)
      200 Always in UTF8 mode.
      331 Please specify the password.
      230 Login successful.
      OK
      
      AT#XFTP="pwd"
      257 "/" is the current directory
      OK
      
      AT#XFTP="ls"
      227 Entering Passive Mode (90,130,70,73,103,35).
      1000GB.zip
      100GB.zip
      100KB.zip
      [...]
      5MB.zip
      upload
      150 Here comes the directory listing.
      226 Directory send OK.
      OK
      
      AT#XFTP="ls","-l"
      227 Entering Passive Mode (90,130,70,73,94,158).
      150 Here comes the directory listing.
      -rw-r--r--    1 0        0        1073741824000 Feb 19  2016 1000GB.zip
      -rw-r--r--    1 0        0        107374182400 Feb 19  2016 100GB.zip
      -rw-r--r--    1 0        0          102400 Feb 19  2016 100KB.zip
      -rw-r--r--    1 0        0        104857600 Feb 19  2016 100MB.zip
      [...]
      -rw-r--r--    1 0        0         5242880 Feb 19  2016 5MB.zip
      drwxr-xr-x    2 105      108        561152 Apr 30 02:30 upload
      226 Directory send OK.
      OK
      
      AT#XFTP="ls","-l","upload"
      227 Entering Passive Mode (90,130,70,73,86,44).
      150 Here comes the directory listing.
      -rw-------    1 105      108      57272385 Apr 30 02:29 10MB.zip
      -rw-------    1 105      108        119972 Apr 30 02:30 14qj36kc9esslej6porartkjks.txt
      [...]
      -rw-------    1 105      108         32352 Apr 30 02:30 upload_file.txt
      226 Directory send OK.
      OK
      
      AT#XFTP="cd","upload"
      250 Directory successfully changed.
      OK
      
      AT#XFTP="pwd"
      257 "/upload" is the current directory
      OK
      
      AT#XFTP="ls","-l"
      227 Entering Passive Mode (90,130,70,73,113,191).
      150 Here comes the directory listing.
      -rw-------    1 105      108      57272385 Apr 30 02:29 10MB.zip
      -rw-------    1 105      108        294236 Apr 30 02:31 1MB.zip
      [...]
      -rw-------    1 105      108        838960 Apr 30 02:31 upload_file.txt
      226 Directory send OK.
      OK
      
      AT#XFTP="cd", ".."
      250 Directory successfully changed.
      OK
      
      AT#XFTP="pwd"
      257 "/" is the current directory
      OK
      
      AT#XFTP="ls","-l"
      227 Entering Passive Mode (90,130,70,73,90,43).
      150 Here comes the directory listing.
      -rw-r--r--    1 0        0        1073741824000 Feb 19  2016 1000GB.zip
      -rw-r--r--    1 0        0        107374182400 Feb 19  2016 100GB.zip
      -rw-r--r--    1 0        0          102400 Feb 19  2016 100KB.zip
      [...]
      -rw-r--r--    1 0        0         5242880 Feb 19  2016 5MB.zip
      drwxr-xr-x    2 105      108        561152 Apr 30 02:31 upload
      226 Directory send OK.
      OK
      
      AT#XFTP="ls","-l 1KB.zip"
      227 Entering Passive Mode (90,130,70,73,106,84).
      150 Here comes the directory listing.
      -rw-r--r--    1 0        0            1024 Feb 19  2016 1KB.zip
      226 Directory send OK.
      OK
    3. Switch to binary transfer mode and download a file from the server.

      AT#XFTP="binary"
      200 Switching to Binary mode.
      OK
      
      AT#XFTP="get","1KB.zip"
      227 Entering Passive Mode (90,130,70,73,84,29).
      
      00000000000000000000000000[...]000000000000
      226 Transfer complete.
      OK
    4. Navigate to the upload folder, switch to binary transfer mode, and create a binary file with the content “DEADBEEF”.

      AT#XFTP="cd","upload"
      250 Directory successfully changed.
      OK
      
      AT#XFTP="binary"
      200 Switching to Binary mode.
      OK
      
      AT#XFTP="put","upload.bin",0,"DEADBEEF"
      227 Entering Passive Mode (90,130,70,73,114,150).
      150 Ok to send data.
      226 Transfer complete.
      OK
    5. Switch to ASCII transfer mode and create a text file with the content “TEXTDATA”.

      AT#XFTP="ascii"
      200 Switching to ASCII mode.
      OK
      
      AT#XFTP="put","upload.txt",1,"TEXTDATA"
      227 Entering Passive Mode (90,130,70,73,99,84).
      150 Ok to send data.
      226 Transfer complete.
      OK
    6. Disconnect from the server.

      AT#XFTP="close"
      221 Goodbye.
      OK
  2. Test an FTP connection to “ftp.dlptest.com”.

    This server does not support anonymous login. Go to DLPTest.com to get the latest login information. After login on, you can create and remove folders and files, rename files, and upload files.

    1. Connect to the FTP server and check the status. Replace user and password with the login information from DLPTest.com.

      AT#XFTP="open","user","password","ftp.dlptest.com"
      220-#########################################################
      220-Please upload your web files to the public_html directory.
      220-Note that letters are case sensitive.
      220-#########################################################
      220 This is a private system - No anonymous login
      200 OK, UTF-8 enabled
      331 User user OK. Password required
      230-Your bandwidth usage is restricted
      230 OK. Current restricted directory is /
      OK
      
      AT#XFTP="status"
      215 UNIX Type: L8
      211 https://www.pureftpd.org/
      OK
    2. Retrieve information about the existing files and folders.

      AT#XFTP="pwd"
      257 "/" is your current location
      OK
      
      AT#XFTP="ls"
      227 Entering Passive Mode (35,209,241,59,135,181)
      150 Accepted data connection
      226-Options: -a
      226 42 matches total
      OK
      .
      ..
      1_2596384601376578508_17-9ULspeedtest.upt
      1_603281663034123496_17-9ULspeedtest.upt
      [...]
      aa_.rar
      write to File.txt
    3. Create a folder and enter it.

      AT#XFTP="mkdir", "newfolder"
      257 "newfolder" : The directory was successfully created
      OK
      
      AT#XFTP="ls","-l","newfolder"
      227 Entering Passive Mode (35,209,241,59,135,134)
      150 Accepted data connection
      226-Options: -a -l
      226 2 matches total
      OK
      drwxr-xr-x    2 dlptest9   dlptest9         4096 Apr 29 19:53 .
      drwxr-xr-x    3 dlptest9   dlptest9        57344 Apr 29 19:53 ..
      +CEREG: 1,"1285","02EF8210",7
      
      AT#XFTP="cd","newfolder"
      250 OK. Current directory is /newfolder
      OK
    4. Switch to binary transfer mode and create a binary file with the content “DEADBEEF”.

      AT#XFTP="binary"
      200 TYPE is now 8-bit binary
      OK
      
      AT#XFTP="put","upload.bin",0,"DEADBEEF"
      227 Entering Passive Mode (35,209,241,59,135,182)
      150 Accepted data connection
      226-File successfully transferred
      226 0.013 seconds (measured here), 310.20 bytes per second
      OK
      
      AT#XFTP="ls","-l","upload.bin"
      227 Entering Passive Mode (35,209,241,59,135,146)
      150 Accepted data connection
      226-Options: -a -l
      226 1 matches total
      OK
      -rw-r--r--    1 dlptest9   dlptest9            4 Apr 29 19:54 upload.bin
    5. Rename the file.

      AT#XFTP="rename","upload.bin","uploaded.bin"
      350 RNFR accepted - file exists, ready for destination
      250 File successfully renamed or moved
      OK
      
      AT#XFTP="ls","-l","uploaded.bin"
      227 Entering Passive Mode (35,209,241,59,135,111)
      150 Accepted data connection
      -rw-r--r--    1 dlptest9   dlptest9            4 Apr 29 19:54 uploaded.bin
      226-Options: -a -l
      226 1 matches total
      OK
    6. Switch to ASCII transfer mode and create a text file with the content “line #1\r\n”.

      AT#XFTP="ascii"
      200 TYPE is now ASCII
      OK
      
      AT#XFTP="put","upload.txt",1,"line #1\r\n"
      227 Entering Passive Mode (35,209,241,59,135,136)
      150 Accepted data connection
      226-File successfully transferred
      226 0.013 seconds (measured here), 0.82 Kbytes per second
      OK
      
      AT#XFTP="ls","-l upload.txt"
      227 Entering Passive Mode (35,209,241,59,135,166)
      150 Accepted data connection
      226-Options: -a -l
      226 1 matches total
      OK
      -rw-r--r--    1 dlptest9   dlptest9           11 Apr 29 19:56 upload.txt
    7. Rename the file.

      AT#XFTP="rename","upload.txt","uploaded.txt"
      350 RNFR accepted - file exists, ready for destination
      250 File successfully renamed or moved
      OK
      
      AT#XFTP="ls","-l uploaded.txt"
      227 Entering Passive Mode (35,209,241,59,135,213)
      200 Zzz...  // (KEEPALIVE response)
      150 Accepted data connection
      226-Options: -a -l
      226 1 matches total
      OK
      -rw-r--r--    1 dlptest9   dlptest9           11 Apr 29 19:56 uploaded.txt
      +CEREG: 1,"1285","02EF8200",7
    8. Delete the files and the folder that you created.

      AT#XFTP="delete","uploaded.bin"
      250 Deleted uploaded.bin
      OK
      
      AT#XFTP="delete","uploaded.txt"
      250 Deleted uploaded.txt
      OK
      
      AT#XFTP="cd", ".."
      250 OK. Current directory is /
      OK
      
      AT#XFTP="rmdir", "newfolder"
      250 The directory was successfully removed
      OK
    9. Disconnect from the server.

      AT#XFTP="close"
      221-Goodbye. You uploaded 1 and downloaded 0 kbytes.
      221 Logout.
      OK

TWI AT commands

Complete the following steps to test the functionality provided by the i2c sensors on the Thingy:91 using the two-wire interface (TWI):

  1. Test the TWI list command using AT#XTWILS. As Thingy:91 connects to the sensors via i2c2, it shows that TWI2 is available:

    AT#XTWILS
    #XTWILS: 2
    OK
    
  2. Test the TWI write command using AT#XTWIW=2,"76","D0". It performs a write operation to the device address 0x76 (BME680), and it writes D0 to the device:

    AT#XTWIW=2,"76","D0"
    OK
    
  3. Test the TWI read command using AT#XTWIR=2,"76",1. It performs a read operation to the device address 0x76 (BME680), and it reads 1 byte from the device:

    AT#XTWIR=2,"76",1
    
    #XTWIR: 61
    OK
    

    The value returned (61) indicates 0x61 as the CHIP ID.

  4. Test the TWI write-and-read command using AT#XTWIWR=2,"76","D0",1. It performs a write-then-read operation to the device address 0x76 (BME680) to get the CHIP ID of the device:

    AT#XTWIWR=2,"76","D0",1
    
    #XTWIWR: 61
    OK
    

    The value returned (61) indicates 0x61 as the CHIP ID.