calibrating STAGES

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cathmart
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calibrating STAGES

Post by cathmart » Mon Apr 13, 2020 6:51 pm

so...i have found a lot of information and gotten help from forums on Building the STAGES bootloader & hex files and have started on the calibration procedure. I have the notes from
https://github.com/forestcaver/MIStagesStuff
and the


I have successfully build the Mutable Virtual Environment and test compiled the Stages.hex & the Bootloader.hex

so to the calibration.....I have the notes on how to do it & the spreadsheet
I think I understand how to test each output and enter it in the spreadsheet and it will give me the final figures I need to put i the final settings.cc then recompile the Stages.hex and flash it...all good.

what I don't understand is how to get to the test/calibration setting on the module.
I've been trying to compile a test.hex & a stages_test.hex & a factory_test_hex with no luck.
do I need to do this?
and then how do I enter the calibration on the module.... the notes say...

2. Edit factory_test.cc - Look for comment that says “AJH” my initials. Where it says #if 0 for the dac calibration, change the zero to one.
3. Compile and flash (erase flash to enter factory test mode) - everything blinks as you are in calibration mode.

I'm sorry I don't understand this.
Can anyone help explain this please.

thanks.

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cathmart
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Re: calibrating STAGES

Post by cathmart » Wed Apr 15, 2020 2:38 am

An answer from another place......Just compile bootloader and main fw. The test is a stand alone util to run on the host machine (not the stm32!) When you flash it, erase first. (If you flash from the make ‘upload’ target it erases it first. I put the comment about erasing as some people used the st utility from windows and didnt erase first)

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forestcaver
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Re: calibrating STAGES

Post by forestcaver » Wed Apr 15, 2020 3:07 am

Essentially the whole process is really hacky - the correct solution is to write a harness and use the serial ports to drive the calibration process and write the results via the existing code. I did most of this work but never finished it.
In the end, I only wanted to calibrate one or two of my own modules so I just hacked in some code really quickly to force the module to output fixed values and then derived the slope and offset for the dac in a spreadsheet. It’s a complete hack and I feel a bit ashamed of it, but it served its purpose for me to get a couple of modules calibrated. I just shared what I did with some quick notes. It’s not very user friendly or very neat but it works and only took 10 minutes or so to do.... I keep meaning to go back and clean it up/finish off an external harness but dont really have the motivation as my modules work fine :-)

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Maltana
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Re: calibrating STAGES

Post by Maltana » Wed Apr 07, 2021 7:13 am

>>>FIXED<<<

Hi there,
today I finally wanted to tackle the calibration process of my two DIY Stages, following forestcavers instructions and repository resources.
I swapped the settings and factory_test cc-s in the vagrant-development folder of stages, after only leaving the standard values in settings (followed by the AJH comment; left the '#if0'). In the factory_test i swapped the DAC_tst 0 to a 1.
Compiling and flashing with 'make -upload' went succesfull. All upper LEDs and sliders are blinking, output LEDs are orange.
I guess how it should be for the calibration mode. However the first pot does not change the ouput values from -1 to 2V. Instead some channels are always around -2,5V and other at around 0V.

Any chance of guessing what went wrong?

Thanks already for the massively helpful resources and code!

Have a good one! :)

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Maltana
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Re: calibrating STAGES

Post by Maltana » Wed Apr 07, 2021 12:02 pm

Got it all working, I recopied the whole fresh Stages data from the github repository and did the steps again.
Set a 1 to the default values in the settings, and it went all smooth from there!

Happy wiggling y'all :)

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