Getting GPS fix

I just started playing around with the IoT applicaiton shield and have some issues.

I can’t get the GPS example to work. I’ve used this as a guide:

My USB cable is connected, the shield seems to be powered one (the PWR red is on, as I established a PPP connection successfully (I can remotely login via SSH). I’ve changed the ports to 1 and 0 in the script since I do not have anything on ttyUSB3 and 2.

I’ve tried all of the USB ports, the script “stops” at “Receiving GPS data”. The unit is placed outside (clear view of the sky) and I left it there for 30minutes. Any help or pointers would be appreciated

I am using a Raspberry Pi 3B

My dmesg output is:
pi@raspberrypi:~ $ dmesg | grep tty
[ 0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=1 snd_bcm2835.enable_compat_alsa=0 snd_bcm2835.enable_hdmi=1 snd_bcm2835.enable_headphones=1 bcm2708_fb.fbwidth=656 bcm2708_fb.fbheight=416 bcm2708_fb.fbswap=1 vc_mem.mem_base=0x3ec00000 vc_mem.mem_size=0x40000000 console=tty1 root=PARTUUID=d899273c-02 rootfstype=ext4 elevator=deadline rootwait
[ 0.000864] printk: console [tty1] enabled
[ 2.523878] 3f201000.serial: ttyAMA0 at MMIO 0x3f201000 (irq = 81, base_baud = 0) is a PL011 rev2
[ 2.531153] 3f215040.serial: ttyS0 at MMIO 0x0 (irq = 53, base_baud = 50000000) is a 16550
[ 7.304308] usb 1-1.5: GSM modem (1-port) converter now attached to ttyUSB0
[ 7.313374] usb 1-1.5: GSM modem (1-port) converter now attached to ttyUSB1
[ 21.771530] option1 ttyUSB0: GSM modem (1-port) converter now disconnected from ttyUSB0
[ 21.772190] option1 ttyUSB1: GSM modem (1-port) converter now disconnected from ttyUSB1
[ 27.832425] usb 1-1.5: GSM modem (1-port) converter now attached to ttyUSB0
[ 27.833087] usb 1-1.5: GSM modem (1-port) converter now attached to ttyUSB1

I have the same GPS not working issue with the 4G Tellit chip, Raspberry Pi 3B

If I try to enable GPS with AT+QGPS=1 it says ERROR

Hello Martin,

Seems you have upgraded your kernel version. Is it v5.4.72?

There is an issue with the driver in the kernel version v5.4.66+

This information has been added to the getting started with the Cellular IoT HAT

Please downgrade the kernel and try again.

Yup I have 5.4.72, will try downgrading and report back. Thanks!

I can confirm everything works fine now, thanks again for the support

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