Issue Getting uart Connection on VOXL2 to PixHawk4 on 5G Hat

John Nomikos 0

Good afternoon,

I have been trying to get a serial connection from the J9 socket of a 5G hat to a PixHawk 4. However, there does not seem to be any data going through ttyHS2.

I triple checked to make sure my physical connection is correct and the wires are in the correct area. They look correct to me.

I have the JST from the J9 socket connected to TELEM2 of the PixHawk 4. The baudrate is set to 921600.

The way I am testing this is by using mavlink-router. I run this command:

mavlink-routerd /dev/ttyHS2:921600 -e {my ip}:14550 -v

It has worked before when connecting to the usb port on the hat via an FTDI cable, but we're trying to get it working with the serial port.

I also decided to follow this to see if I could get anything from sending stuff to the port. I saw nothing. But I could be completely wrong that this is a valid way of testing the connection:

(In one terminal):

cat -v < /dev/ttyHS2

(In another terminal):

echo -ne '\033[2J' > /dev/ttyHS2

I did not see anything on the first terminal.

Also, I tried using voxl-mavlink-server to test this. I am on a beta platform (system-image: 1.5.5-M0054-14.1a-perf), so options are a little bit different than what I'm used to.

I had this set as my configuration file:

{
        "primary_static_gcs_ip":        "192.168.8.10",
        "secondary_static_gcs_ip":      "192.168.8.11",
        "onboard_port_to_autopilot":    14556,
        "onboard_port_from_autopilot":  14557,
        "gcs_port_to_autopilot":        14558,
        "gcs_port_from_autopilot":      14559,
        "en_external_uart_ap":  false,
        "autopilot_uart_bus":   2,
        "autopilot_uart_baudrate":      921600,
        "en_external_ap_timesync":      1,
        "en_external_ap_heartbeat":     1,
        "udp_mtu":      0,
        "gcs_timeout_s":        4.5
}

I believe "autipilot_uart_bus" was what I had to set to 2 to get it to go through ttyHS2. I could not see any data passing through though.

I am curious what the problem could be. Any help would be much appreciated.

wilkinsaf

For context, the UART/USB addon board is working (https://docs.modalai.com/voxl2-usb3-uart-add-on-user-guide/)
and we are using cables provided by ModalAI. So, it appears that it is just the 5G modem carrier board that is not letting this through

wilkinsaf

for context as well, here are the serial devices by-id page. All of them are from Quectel.

Dont think that matters, but just trying to add context.

Also, the 5G carrier board is operational. We see the wwan0 interface

wilkinsaf

https://forum.modalai.com/topic/2141/external-autopilot-not-getting-serial-communication-with-m0090-board/8?_=1688077180364

I think this might be the issue

tom

@wilkinsaf That must be the VOXL1 flavor

wilkinsaf

This post is deleted!

wilkinsaf

@tom Damn.... welp... that would explain what's going on.
Back to the ModalAI store. Thanks for confirmation Tom

wilkinsaf

Can confirm ordering and installing a new one fixed our issue

tom

@wilkinsaf Thanks for the feedback