Temperature compensation not working?

[MASSIMILIANO CHERSICH]

I've just finished to build a myforcuserpro2 prototype with a classic
DRV8825HW203_MT configuration (+ push buttons).
I've activated the temperature coefficient (set at 10 steps per degree).
Despite the temperature sensor seems reporting correctly the actual
temperature the feedback compensation mechanism is not working: the motor
does not move with temperature changes.
Any advice?

P.S. I will never be able to thank the author of this project enough:
THANKS Robert!

[brownrb]

Hi
Do the following using the Arduino IDE Serial port monitor

1. Connect focuser to computer via USB
2. Start Arduino IDE and then open the Serial port monitor
3. In botton right ensure it says No line ending and speed is 9600
4. If not, change it, close the serial port window then reopen it
5. Send the command :25# to the controller
6. The controller should respond with A1#

If this is corrent (A1#) then proceed
Else, your firmware is not configured correctly if you get A0#

1. Send the command :26# to the controller
2. The response should be somehing like B20# where 20 is your number of coeffient steps per degree
3. Send the command :24# to the controller
4. The response should be 10# (0 meaning temp comp disabled)
5. Now send the command :231# to the controller
6. Now send the command :24# to the controller
7. The response should be 11#
8. At this point if the response was 11# the controller is in temperature compensation mode and will only move if there is a drop of 1 degrees or more
9. You can verify by sending :057000# to the controller which is a move command. The focuser should not move.

[brownrb]

I am assuming you are using firmware Focuserv277_DRV8825_HW203.ino
Previous versions had some issues.

Also be aware that 10 steps per degree, though normal, is such a small amount and you are pretty likely to even see that if looking directly at the motor - even more so if its 1/2 or 1/4 stepping.

[MASSIMILIANO CHERSICH]

All tests gone right. With "Refresh Position" checkbox checked in Win App (2.4.1.6) should I see "Focuser Position" box to change with temperature isn't right?

[brownrb]

Yes, but again easy to query using :00# from the serial port monitor.

You could hold probe in hand for a few seconds to warm it up
:06# gets temperature
Then get position :00#
Then enable tc :231#
then when you think motor has moved by TC
get position :00#
which should be different (less) from first :00#

[MASSIMILIANO CHERSICH]

Sorry for delay. This weekend I will test TC as described.