Unable to Access GNSS Receiver

[nixone]

Hello OZZMAKER Community,

I’m facing an issue with my OZZMAKER SARA-R5 LTE-M GPS + 10DOF module, specifically related to accessing the GNSS receiver. Despite multiple attempts to establish communication using tools like minicom, screen, and cat, I’m not receiving any responses or data, and I’m unable to execute any commands. I’m running the board on top of a Pi Zero W, and all other sensors seem to be operating as expected.

 dmesg | grep tty
[ 0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=1 snd_bcm2835.enable_headphones=0 snd_bcm2835.enable_hdmi=1 snd_bcm2835.enable_hdmi=0 video=Composite-1:720×480@60i smsc95xx.macaddr=B8:27:EB:20:FC:EF vc_mem.mem_base=0x1ec00000 vc_mem.mem_size=0x20000000 console=tty1 console=ttyS0,115200 root=PARTUUID=0be438f9-02 rootfstype=ext4 fsck.repair=yes rootwait
[ 0.001516] printk: console [tty1] enabled
[ 3.811555] 20201000.serial: ttyAMA0 at MMIO 0x20201000 (irq = 81, base_baud = 0) is a PL011 rev2
[ 3.823791] printk: console [ttyS0] disabled
[ 3.827084] 20215040.serial: ttyS0 at MMIO 0x20215040 (irq = 53, base_baud = 50000000) is a 16550
[ 4.862550] printk: console [ttyS0] enabled
[ 9.063712] systemd[1]: Created slice system-getty.slice.
[ 9.150244] systemd[1]: Created slice system-serial\x2dgetty.slice.

uname -a
Linux pi0 6.1.21+ #1642 Mon Apr 3 17:19:14 BST 2023 armv6l GNU/Linux

[Mark Williams]

this line shows that it looks like you still have the console enabled
[ 4.862550] printk: console [ttyS0] enabled

 

Have you done this?

sudo raspi-config
Select interfacing options -> Serial -> No -> Yes

 

And then Yes to reboot

 

Then, once the Pi is back up use minicome to connect to serial0

minicom 115200 -D /dev/serial0

Enter “AT” hit enter and you should get “OK” response

Mark --OzzMaker.com --

[nixone]

Thank you for your previous instructions. I carefully executed each step as advised. After rebooting the system, I initiated the minicom 115200 -D /dev/serial0 command. However, the problem still persists, and I’m unable to interact with the module as I cannot input AT commands.

dmesg | grep tty
[ 0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=1 snd_bcm2835.enable_headphones=0 snd_bcm2835.enable_hdmi=1 snd_bcm2835.enable_hdmi=0 video=Composite-1:720×480@60i smsc95xx.macaddr=B8:27:EB:20:FC:EF vc_mem.mem_base=0x1ec00000 vc_mem.mem_size=0x20000000 console=tty1 root=PARTUUID=0be438f9-02 rootfstype=ext4 fsck.repair=yes rootwait
[ 0.001508] printk: console [tty1] enabled
[ 3.812014] 20201000.serial: ttyAMA0 at MMIO 0x20201000 (irq = 81, base_baud = 0) is a PL011 rev2
[ 3.824402] 20215040.serial: ttyS0 at MMIO 0x20215040 (irq = 53, base_baud = 50000000) is a 16550
[ 7.788563] systemd[1]: Created slice system-getty.slice.

[nixone]

I am actually able to access the module as intended now.

Thank you for your support.

[Author]

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