APM2.8 "Got param $R0_EXT_STAT

Hello Everyone,

I just want you to know that I am very new at this.

When I start to click connect using mission planner, it got stuck with "Got para $R0_EXT_STAT, any idea what’s going on? I am using APM 2.8 with uploaded ArduPlane V3.7.0 firmware.

I’m a ArduCopter user and clicked on this because of how you have the issue categorized But I will try to help.
I was taught not to use the wizard.
So let’s back up a bit.
Connect the USB to the APM then connect the USB to the computer (best practice)
Go to Install Firmware.
Select a different vehicle, any vehicle and load that firmware.
Trying to clear out the firmware that is possibly corrupt.
After loading, wait 30 seconds.
Disconnect the USB from the computer.

Reconnect USB to the computer.
Load the proper ArduPlane firmware.
After loading wait 30 seconds and disconnect.

Reconnect USB to computer and see if you can connect to the APM.
If you can, since you skipped the wizard, your next step is to calibrate accelerometers.
You can find that under mandatory hardware.
Just follow the prompts.
Then, calibrate compass.
Finally, follow through with failsafes.
Those are a must.

This is where you need to re-categorize your issue listing from ArduCopter to ArduPlane.
I am not sure how planes are setup after this point.
But that should get you going