uping doesn´t work on LTE-M1

[fruiz1113]

I am attached and connected to LTE-M in Argentina :
lte.send_at_cmd('at+cgdcont=1, "IP", "datos.personal.com"')
Also enable the functionality +CFUN=1

When I import uping.py file and try uping.ping('google.com') I got an error in line 52


I thinks it is a modem configuration issue, something I have to define as I was playing with different at commands after lte.pppsuspend() , and one time when I return to LTE lte.pppresume() , it worked , but I didn´t save the configuration and since then I can not make it run.
Any idea to configure in the modem or in the uping script ?[uping.py]

Also I can not run the simple LTE example

s = socket.socket()
s = ssl.wrap_socket(s)
s.connect(socket.getaddrinfo('www.google.com', 443)[0][-1])
s.send(b"GET / HTTP/1.0\r\n\r\n")
print(s.recv(4096))

It fails in the s.connect(socket.getaddrinfo('www.google.com', 443)[0][-1]) line
(/assets/uploads/files/1584659765014-uping.py)

[fruiz1113]

An interesting thing is that If I put IPV4 instead of IP it works , but after a minute if I try again it throws error in line 55

addr = usocket.getaddrinfo(host, 1)[0][-1][0] # ip address

[kjm]

1. I've found pppsuspend/resume to be unreliable, maybe avoid them for the time being & use lte.disconnect() instead if you want to run an at cmd
2. Try to limit yourself to one query per post, I've found it improves your chances of getting a reply if you don't conflate multiple issues.
3. There are multiple versions of most micropython libraries, many of them not functional on pycom product. Try running the version of ping below on an attached/connected gpy

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 uos

    # 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.ARRAY | 4, 2 | uctypes.UINT8),
        "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[0:2] = uos.urandom(2)
    h.seq = 1

    # init socket
    #sock = usocket.socket(usocket.AF_INET, usocket.SOCK_RAW, 1)
    sock = usocket.socket(usocket.AF_INET, 3, 1)
    sock.setblocking(0)
    sock.settimeout(timeout/1000)
    try:
        addr = usocket.getaddrinfo(host, 1)[0][-1][0] # ip address
    except IndexError:
        not quiet and print("Could not determine the address of", host)
        return None
    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 = (utime.ticks_us()-h2.timestamp) / 1000
                    t_elasped = utime.ticks_diff(h2.timestamp, utime.ticks_us()) / 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)

ping('google.com')

[fruiz1113]

@kjm thanks for your reply , the problem was the pppsuspend/resume ,absolutely it hangs the modem for internet. The uping file and the ping file you have sent works properly.