“PreArm: Internal errors 0x800000 l:181 stack_ovrfl”
I get such message during calibration. Is that mean that it doesn’t work ?
There is also parameter TCAL_ENABLED should I set it to 1 or 2 like INS_TCALn_ENABLE
The advice to me was to not use this, it was done for a specific frame/fc and is largely useless elsewhere
You could post your logs here, maybe it will get more attention: Internal errors 0x800000 I: 181 stack_ovrfl during/after IMU temperature calibration · Issue #19022 · ArduPilot/ardupilot · GitHub
So I updated the software and calibrated temperature of IMU and the problem still exist during first boot Cube Black showing “Yaw inconsistent” etc…
Then I am out of ideas.
It works fine here, on multiple flight controllers, none has this problem after the temperature compensation.
From the last logfile it seems, that the temperature calibtaion did not finish. After the process finishes the INS_TCALn_ENABLE should automatically change from 2 to 1.
Also your temperature ranges are not far enough apart. For example your TCAL1_TMIN is 26.6 °C, which is way too high and TCAL3_TMAX is only 32.6 °C which is not enough (the heater heats the IMUs to 45 °C by default).
Consider redoing the calibration from your kitchen freezer to at least 50 °C (the docs recommend 65). Use your oven on low temperature or a heatgun, etc…
But the heater in Cube black can’t heat IMUs in 10 minutes from 26.6 °C to 45 °C. I was trying to do calibration in -1 °C and in +20 °C. I think this heater is just to slow or 10 minutes for calibration is to short.
Use your oven or a heat gun.
The calibration can run for longer, than 10 minutes. It just stops if the temperature doesn´t increase after 10 minutes.
I was checking that on Raw_Temp in Mission Planner and temperature was higher and higher so that’s strange. Maybe I will try to use hair dryer. It will be quite hard to put octocopter into oven 
and I don’t want to dismantle it.
Where do these 10 minutes come from? AFAIK it takes as long as needed.
this 10 minutes comes from the wiki:
The calibration process has a 10 minute timeout. If an IMU doesn’t increase it’s temperature by at least 0.5 degrees C over a 10 minute period then the calibration will complete and the parameters will be saved up to the point the temperature reached.
HI I tried again. Newest firmware 4.1.5. I started from 13 °C and max is set to 65 °C. During calibration I get "PreArm: Internal errors 0x800000 I:181 stack_overfl and EKF IMU1 forced reset…but finally I get final calibration message. For now I don’t have yaw inconsistent messages so It looks like calibration helped thanks.
Did you calibrate all IMUs at once or each separately? I get strange overflow messages when I try to do the onboard calibration (I will switch to offline calibration).
I did all IMUs at ones check higher… I had also strange messages about STACK_OVERFL.
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