Issues connecting internet over LTE on soracom network



  • So I have developed an application to run on the pycom GPy module which is supposed to connect to an AWSIoTMQTT server. Everything works when I have internet access available over WiFi, but when I try the same program except using an LTE connection I get "OSError: Network card not available" error. The GPy attaches and connects to the soracom network each time and I can successfully sync the rtc via an ntp server. It's just anytime I try to create a connection via a socket I get that error. I am experiencing the same issue with the following uping module in attempts to ping google:

    # ┬ÁPing (MicroPing) for MicroPython
    # copyright (c) 2018 Shawwwn <shawwwn1@gmail.com>
    # License: MIT
    
    # Internet Checksum Algorithm
    # Author: Olav Morken
    # https://github.com/olavmrk/python-ping/blob/master/ping.py
    # @data: bytes
    def checksum(data):
        if len(data) & 0x1: # Odd number of bytes
            data += b'\0'
        cs = 0
        for pos in range(0, len(data), 2):
            b1 = data[pos]
            b2 = data[pos + 1]
            cs += (b1 << 8) + b2
        while cs >= 0x10000:
            cs = (cs & 0xffff) + (cs >> 16)
        cs = ~cs & 0xffff
        return cs
    
    def ping(host, count=4, timeout=5000, interval=10, quiet=False, size=64):
        import utime
        import uselect
        import uctypes
        import usocket
        import ustruct
        import machine
    
        # prepare packet
        assert size >= 16, "pkt size too small"
        pkt = b'Q'*size
        pkt_desc = {
            "type": uctypes.UINT8 | 0,
            "code": uctypes.UINT8 | 1,
            "checksum": uctypes.UINT16 | 2,
            "id": uctypes.UINT16 | 4,
            "seq": uctypes.INT16 | 6,
            "timestamp": uctypes.UINT64 | 8,
        } # packet header descriptor
        h = uctypes.struct(uctypes.addressof(pkt), pkt_desc, uctypes.BIG_ENDIAN)
        h.type = 8 # ICMP_ECHO_REQUEST
        h.code = 0
        h.checksum = 0
        h.id = machine.rng() & 0xffff
        h.seq = 1
    
        # init socket
        sock = usocket.socket(usocket.AF_INET, 3, 1)
        sock.setblocking(0)
        sock.settimeout(timeout/1000)
        addr = usocket.getaddrinfo(host, 1)[0][-1][0] # ip address
        sock.connect((addr, 1))
        not quiet and print("PING %s (%s): %u data bytes" % (host, addr, len(pkt)))
    
        seqs = list(range(1, count+1)) # [1,2,...,count]
        c = 1
        t = 0
        n_trans = 0
        n_recv = 0
        finish = False
        while t < timeout:
            if t==interval and c<=count:
                # send packet
                h.checksum = 0
                h.seq = c
                h.timestamp = utime.ticks_us()
                h.checksum = checksum(pkt)
                if sock.send(pkt) == size:
                    n_trans += 1
                    t = 0 # reset timeout
                else:
                    seqs.remove(c)
                c += 1
    
            # recv packet
            while 1:
                socks, _, _ = uselect.select([sock], [], [], 0)
                if socks:
                    resp = socks[0].recv(4096)
                    resp_mv = memoryview(resp)
                    h2 = uctypes.struct(uctypes.addressof(resp_mv[20:]), pkt_desc, uctypes.BIG_ENDIAN)
                    # TODO: validate checksum (optional)
                    seq = h2.seq
                    if h2.type==0 and h2.id==h.id and (seq in seqs): # 0: ICMP_ECHO_REPLY
                        t_elasped =  abs(utime.ticks_diff(utime.ticks_us(), h2.timestamp)/ 1000)
                        ttl = ustruct.unpack('!B', resp_mv[8:9])[0] # time-to-live
                        n_recv += 1
                        not quiet and print("%u bytes from %s: icmp_seq=%u, ttl=%u, time=%f ms" % (len(resp), addr, seq, ttl, t_elasped))
                        seqs.remove(seq)
                        if len(seqs) == 0:
                            finish = True
                            break
                else:
                    break
    
            if finish:
                break
    
            utime.sleep_ms(1)
            t += 1
    
        # close
        sock.close()
        ret = (n_trans, n_recv)
        not quiet and print("%u packets transmitted, %u packets received" % (n_trans, n_recv))
        return (n_trans, n_recv)
    

    Has anyone experienced this issue or know if there is a setup step that I might be missing? My LTE modem setup procedure looks like this:

    lte = LTE()
    lte.reset()
    lte.send_at_cmd('AT\!="clearscanconfig"')
    lte.send_at_cmd('AT!="RRC::addScanBand band=26"')
    lte.send_at_cmd('AT!="RRC::addScanBand band=18"')
    lte.send_at_cmd('AT+CGDCONT=1,"IP","soracom.io"')
    lte.send_at_cmd('AT+CGAUTH=1,2,"sora","sora"')
    lte.send_at_cmd('AT+CFUN=1')
    sleep(3)```


  • +1 to this issue.


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