Firmware influence on StallGuard

[boazran]

Hi,
We are having a change in the way the stallguard behaves on the TMCM 303/SG module.
We are using this module for more than 3 years using firmware V3.17 and optimized it with this firmware.
Few days ago we started installing new modules with firmware V3.3 and we have problems with the stallguard.
We performed downgrade of the firmware to 3.16 (we don't have the V3.17) and the problem disappeared. Upgrading to the latest version from the website to V3.34 brought back the problem.
So it looks like a firmware issue, something in firmware V3.34 behaves differently with the stallguard.
We also noticed that the motor controller IC on the module has changed from 246-AP to 246A-AP, does this also supposed to make new behaviors?
In order to find the fastest solution for the problem, please advise with the following questions:
1. Can we receive firmware V3.17 by e-mail?
2. Is there a problem downgrading the new modules that arrive with to the old V3.17?

Thanks

[Olav Kahlbaum (TRINAMIC)]

The StallGuard algorithm has been optimized in firmware revision 3.30. In firmware revisions prior to 3.30, sometimes "false alarms" were possible (in some rare cases the motor had been stopped even if there was no stall). However in some applications need re-adjusting of the stall threshold values will be needed.
The 246A-AP has a better microstep performance, it does not influence the behaviour of StallGuard.
We can send you an e-mail with V3.17. Downgrading a module to an older firmware version can be done without any problems.