Hi all, just bought a new airspeed sensor (MS4525D) and It isn’t being detected by mission planner, says sensor not found on bootup. Cycled through all the bus #’s, checked type is correct and wires going to the right pins. Using UART8 (GPS2) to route through to I2c and have baud set to 57900. Nothing seems to work. I checked the sensor with my multimeter and it is getting power so I know the sensor is ok. I tried to swap back to the old sensor and that now has the same issue
Baud rate is immaterial, as I2C has nothing to do with UART comms. It does look like the GPS2 port has I2C pins, but I think you may very well have miswired it.
What other parameters have you set?
The I2c bus doesn’t work directly with mission planner according to documentation
I have type = 1
Setting for analog is disabled
I have all options unchecked in ARSPD_options
Please link to whatever documentation you are referencing, as this makes little sense.
The list of UART mapping doesn’t include the I2c port
but GPS2 pins are apparently I2c_bus 2
Ok, Mission Planner is just the GCS, so it has nothing to do with I2C.
UART comms have nothing to do with I2C.
The GPS2 port includes I2C pins because some GPS modules use I2C compasses alongside the serial GPS pins.
All of that to say, yes, you can connect your I2C sensor to the I2C pins on the GPS2 port, but you seem to have some wild misconceptions about its use.
I2C devices do not require any “crossing over” of wires like UARTs, so connect SCA → SCA and SDL → SDL.
If I’m interpreting the hwdef properly, you need to set ARSPD_BUS,2.
Yes, this is what I meant, setting ARSPD_BUS to 2 and routing the wires to the correct pins still cause the issue IE not connecting
So theoretically the I2c port can also be used without issue?
Yes? I don’t really understand this question after having explained above… And there is no theory. It’s practical and possible.
Well previously I was only able to get it to work through the GPS2 port, and not the I2c port
Should the UART8 be set to something or is it completely irrelevant – I have it set to airspeed
THAT is very likely the problem. None of your serial ports should be set to airspeed.
oh - what should I set it to?
Set SERIAL4_PROTOCOL,-1 (which is UART8).
Will try thanks so much
Fixed! it was the UART setting all along - thanks a ton