Upgraded LTE-M modem FW and now I can't see any bands besides band 13....



  • Hi all,

    I've been working on improving the connection scheme I've been using by trying to have the modem scan available Bands to connect to prior to connecting to the network in the hopes that in locations where i cant access Band 13 (Verzion) one of the other bands may be available or have less traffic.
    Im using a Gpy, running 1.20.0.rc13 and I was using modem FW 39529. Prior to upgrading the modem FW to the latest version (41065) I was able to scan bands with the AT+SQNINS=0 cmd and received a list of 6 bands across 3 towers in the area (Bands 4,5,13, and 12). But now that ive upgraded, when i send the same AT command i am only getting a reply of the Band 13 at the tower i have been connecting at.
    If i blindly tell the modem to attach to band 4 or band 5 it still seems to attach and connect properly to Verizons network and i can still send and receive data but i can no longer "see" those bands when scanning.
    Has anyone had a similar experience? Any idea whats going on? Or is there another way to scan for available bands?
    Thanks,

    -Jeef

    Scanning....

    Radio Band: 13, RF Channel#: 5230, Cell ID: 413, BW: 10 MHz, Signal Power: -100.60 dBm, Signal Quality: -14.40 dB

    def scanNet(send_at_cmd, deinit, init):
        try:
            at_test = send_at_cmd('AT+SQNINS=?')
            if 'OK' in at_test:
                pass
            else:
                raise ValueError
        except:
            print("No reply from modem, or unable to process AT commands\
                 please reset modem and try again")
            return False
        else:
            while True:
                band_scan = ['']
                while band_scan == ['']:
                    print('\r\nScanning', end='')
                    band_scan = send_at_cmd('AT+SQNINS=0').strip('\r\n\r\nOK').split('\r\n+SQNINS:')
                    for x in range(0,4):
                        print('.', end='')
                        sleep(0.25)
                if band_scan[0].split(',')[5] == '':
                    print('\r\nCycling modem for band scan, please wait',end='')
                    deinit(reset=True)
                    for x in range(0,5):
                        print('.', end='')
                        sleep(0.75)
                    init()
                    print('\r\nReinitializing modem',end='')
                    for x in range(0,5):
                        print('.', end='')
                        sleep(0.25)
                else:
                    break
            print('\n')
            for x in range(0,len(band_scan)):
                print("Radio Band: {0}, RF Channel#: {1}, Cell ID: {2}, BW: {3} MHz, Signal Power: {4} dBm, Signal Quality: {5} dB"\
                .format(band_scan[x].split(',')[1],band_scan[x].split(',')[6],\
                    band_scan[x].split(',')[7],band_scan[x].split(',')[8],\
                        band_scan[x].split(',')[9],band_scan[x].strip('\r\n\r\nOK').split(',')[10]))
    

Log in to reply
 

Pycom on Twitter