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Suddenly Problems with PEC


Thomas Westerhoff
 

I am currently having some issues with my OnStep regarding PEC.
What happened? I flashed the firmware with new settings for the motors. In the process, I lost the PEC from the NV. Fortunately I had saved the PEC in SkyPlanetarium. So I imported it there again and wrote it into the EEPROM (NV). I thought that everything would be OK again.
But now I noticed that my RA axis inexplicably stops for a few seconds. At first I suspected that this could be due to low temperature, hard grease in the gearbox and too low motor current. So I set the motor current in config.h to the maximum possible (1.5A with TMC2130). I noticed that with some flashes the PEC is deleted, but with others not. Anyway, I had saved it via SkyPlanetarium.
Why is the PEC sometimes lost during flashing and sometimes not?

Now I noticed, when the PEC was not yet restored to the OnStep, that the RA axis ran cleanly, only without PEC.
After importing the PEC (Pec_loaded.csv), however, the same problem again. Temporary standstill of the wormwheel for several seconds. PEC switched off and everything is OK again. Therefore I have the assumption that something does not work cleanly when importing the PEC. I have attached the file (Pec_loaded.csv). Can someone look at it, if there is something wrong?

Then I have two final questions about SkyPlanetarium.
Why is the PEC not displayed in the diagram after importing from a file (e.g. Pec_loaded.csv)?
Why, after importing the PEC from a file and writing it to the EEPROM, does clicking the export button export a file with 0 values (Pec_saved.csv)? There is only a file with valid PEC values exportet, if the PEC is recorded with a camera.
I would have somehow assumed that the import file and the export file should be identical during import and subsequent export.

--
Thomas Westerhoff
Kirchheim Observatory /Germany
http://sternwarte-kirchheim.de/
https://www.facebook.com/VolkssternwarteKirchheim/


Howard Dutton
 

OnStep version?


Howard Dutton
 

On Tue, Jan 12, 2021 at 08:48 AM, Howard Dutton wrote:
OnStep version?
Have to ask since...
https://onstep.groups.io/g/main/message/28605


Howard Dutton
 

On Tue, Jan 12, 2021 at 08:20 AM, Thomas Westerhoff wrote:
I am currently having some issues with my OnStep regarding PEC.
What happened? I flashed the firmware with new settings for the motors.
Depending on what those settings were it could make all prior PEC data tables incompatible.

In the process, I lost the PEC from the NV. Fortunately I had saved the PEC in SkyPlanetarium. So I imported it there again and wrote it into the EEPROM (NV). I thought that everything would be OK again.
But now I noticed that my RA axis inexplicably stops for a few seconds. At first I suspected that this could be due to low temperature, hard grease in the gearbox and too low motor current. So I set the motor current in config.h to the maximum possible (1.5A with TMC2130). I noticed that with some flashes the PEC is deleted, but with others not. Anyway, I had saved it via SkyPlanetarium.
1.5A is a LOT for TMC2130's they may very well cut out due to overheating

Why is the PEC sometimes lost during flashing and sometimes not?
Sometimes the NV layout/structure changes and I opt to invalidate prior settings to avoid problems?

Now I noticed, when the PEC was not yet restored to the OnStep, that the RA axis ran cleanly, only without PEC.
After importing the PEC (Pec_loaded.csv), however, the same problem again. Temporary standstill of the wormwheel for several seconds. PEC switched off and everything is OK again. Therefore I have the assumption that something does not work cleanly when importing the PEC. I have attached the file (Pec_loaded.csv). Can someone look at it, if there is something wrong?
More information is needed, a Config.h file would be nice.

Then I have two final questions about SkyPlanetarium.
Why is the PEC not displayed in the diagram after importing from a file (e.g. Pec_loaded.csv)?
That is not currently supported.

Why, after importing the PEC from a file and writing it to the EEPROM, does clicking the export button export a file with 0 values (Pec_saved.csv)? There is only a file with valid PEC values exportet, if the PEC is recorded with a camera.
I would have somehow assumed that the import file and the export file should be identical during import and subsequent export.
Not sure, perhaps the import failed?

Once I have that Config.h file I will look into it.


Howard Dutton
 
Edited

On Tue, Jan 12, 2021 at 09:19 AM, Howard Dutton wrote:
Why, after importing the PEC from a file and writing it to the EEPROM, does clicking the export button export a file with 0 values (Pec_saved.csv)? There is only a file with valid PEC values exportet, if the PEC is recorded with a camera.
I would have somehow assumed that the import file and the export file should be identical during import and subsequent export.
Not sure, perhaps the import failed?

I took a look at what I have and was able to load the PEC data file... but only after fixing it.  An export function locale bug resulted in floating point using "," where It expects "," so fails.

I patched for this issue in 4.59:
http://www.stellarjourney.com/assets/downloads/sky4.59.zip

My OnStep's PEC buffer width isn't right (600 seconds vs. 207) but the curve should look familiar:



The corrected PEC export file (replacing "," with ".") is attached.


Thomas Westerhoff
 

Hello Howard,
Yes, the decimalseparator was the problem. Yesterday evening I opened the PEC file in an text editor and replaced the "," with "." and it worked well. 
I live in Germany and therfore the "," is our common decimalseparator in Windows language and region settings. I wll try the latest version of SkyPlanetarium now. 

--
Thomas Westerhoff
Kirchheim Observatory /Germany
http://sternwarte-kirchheim.de/
https://www.facebook.com/VolkssternwarteKirchheim/