Parameter screw up: THR_ACCEL_P *and* THR_ACCEL_I

MP 1.2.92 build 1.1.5111.11703 (and MP1.2.91) with AMP 2.0 running AC 3.1 Hex, Windows XP SP3, German Version

Problem: THR_ACCEL_P and THR_ACCEL_I are showing way out of range data after touching Basic Pids: “Throttle Accel” Slider. Copter jumping up and down accordingly.

Details: Config/Tuning -> Basic Pids: “Throttle Accel” Slider. Changing it to value “0,5” seems to write wrong data and data ranges for THR_ACCEL_P and THR_ACCEL_I which I never touched. Instead of THR_ACCEL_P at 0,75 I got 75 (range should be 0,5 - 1,5). THR_ACCEL_I shoots up from 1,5 to 150 (normal range 0 - 3,0). The effects were quite obvious: copter jumping up and down massively as soon I switched into Alt Hold or Loiter even with Sonar disabled.

Entering the correct parameters in the “Full Parameter List” using “0,75” and “1,5” with a comma and not “0.75” with a dot did the trick to set them back to normal. After this the parameters were also shown corretly in the Basic Pids and AMP:Copter Pids again.

Interstingly enough loading an earlier parameter file in the Full Paramter List did not fix the problem.

Best Wishes,


Here are some screen shots with comments:

[attachment=4]1 Basic Pids before change Throttle Accel range 0,5 - 1,5.jpg[/attachment]

[attachment=3]2 APM copter Pids before change Throttel Accel p 0.75 I 1.5.jpg[/attachment]

[attachment=2]3 Full Para before Thr Accel I 1.5 Thr Accell P 0.75.jpg[/attachment]

[attachment=1]4 basic pids Throttl Accel 75.jpg[/attachment]

[attachment=0]5 APM Copter Pids Throttle Accel I 150.jpg[/attachment]

the simple pid screen is doing exactly what its mean to. if you want to use custom numbers, please don’t use the simple pid screen

Are you saying you can’t replicate the problem? I don’t want custom numbers. All I do is changing Throttle Accel slider to 0,5 in the Basic Pids screen. What I expect it to do is (all numbers are with comma decimal mark)

  • THR_ACCEL_P gets set to 0,5
  • (any maybe THR_ACCEL_I gets set to 1,5)

What I get instead:

  • THR_ACCEL_P gets set to 75 (its range is only 0,5 - 1,5!)
  • THR_ACCEL_I gets set to 150 (its range is only 0,000 - 3,000!)
  • The max range of the Throttle Accel slider in the Basic Pids screen changes from 1,5 to 75 (out of range)

You can see in the command line of the Basic Pids screen “set THR_ACCEL_I 150”. That however doesn’t explain the THR_ACCEL_P out of range number and range change. Wrong data type? Wrong pointer? Just guessing… It is not just a display problem either as the numbers have shown the expected (bad) behaviour in flight.

thanks for the clarification, I will check it out.

this should now be fixed in 1.2.93

thx for the fix. Verified with 1.2.94. All fine.