Topics created by Andrew Keefe

I have discovered that the entire module seems to stop. I had been assuming it was the UART that was failing. Is there some PX4 setting where when a telemetry link occurs that something would stop/pause running modules?

I verified the UART is working fine using the loopback method, at a few different baud rates. I think the issue is the sensor itself must be encoding the packets differently than I am reading them. I might need to reduce the baud rate down to 9600 and review the data on the oscilloscope.

The Arduino's SoftwareSerial library didn't work properly until I inverted the input, but I didn't see that option for the linux UART.

I am connecting my RFD 900+ to the J5 connector on the Flight Core. The radio is configured for 57,600 baud.

I don't have any experience setting mavlink "modes."

This is an underwater vehicle, so I only communicate with it on the bench. My hope is to not have to open up the pressure vessel to pull off the data logs, which is our current method.

Yes, this "can" work, but it is not ideal due to the many unknown variables on someone's host PC. Hence it is not a default option, and we would not recommend it. Issues can range from USB VBUS being out of spec (as it is, it is allowed +/- 10% which puts it in on the edge of our needs), and most "correctly designed" PCs will not provide more than 100mA unless a device is enumerated that asks for more. I'm not sure if all version of PX4 do that correctly. 100mA is insufficient for most use cases.
In a strictly "QGC config" mode, I can see this work, but it is not something we plan on supporting on this version board due to those risks above. This also opens the door for someone to leave that power feed in-place while then later connecting the power module which will create a serious power rail shorting problem between the module and the PC.
However, we do have a design already figured out that can take USB power for QGC/Config type of applications, and it validates the VBUS through a smart fuse/mux before using it. This will allows us to globally claim support, and if someone's system is not correct or out of range, we protect the HW.
Stay tuned!

Ah, when I run the PWM program there is no chatter on the PWM signals, so I'm going to review that code again and compare it to mine.

Hey @Andrew-Keefe ,

This isn't something I've tried. Curious as to what the setup looks like if you're up to share more details.

Thanks,
Travis

Hi @Andrew-Keefe,

I'm not positive on this one. I have an example of using UART for an ESC here, and I remember having to be careful what task was opening the UART port:

https://github.com/modalai/px4-firmware/blob/modalai-1.11/src/drivers/uart_esc/modalai_esc/modalai_esc.cpp#L736

Here's opening of the port (note: this is beta level code)

https://github.com/modalai/px4-firmware/blob/modalai-1.11/src/drivers/uart_esc/modalai_esc/modalai_esc_serial.cpp#L48

Thank you @modaltb. I was able to control the LED with my code (yellow = waiting for serial, blue = data valid, red = data not valid).

Well, we aren't routing the 5V on that little M0022 board to prevent it being used to drive servos (for this concern). But 5V does come down to the connector, so it could be soldered to, and you could create solder bridges on the bottom of the board. Not ideal, but 5V is there, just not routed....

I know this is kinda an old post but I have created a driver for px4 that can use both flavors of the MS5837 the bar2 and bar30. I will create a pull request with px4 so it will be available.

Thanks @modaltb , that worked! I had to set it to run as a background function using the &. It's running perfectly now.

I probably want to rewrite it as a task, but that example code looked tough to follow. I wish the PX4 developer manual included more step by step tutorials, like the ROS tutorials.

Hi Andrew,

We have other folks using it for controlling ESCs, let me try to see what I can find as far as examples, we don't have one in our repos.

PX4 itself has a UAVCAN implementation they've been working on that might be of help: https://dev.px4.io/master/en/uavcan/index.html

Thanks!
Travis