High level interface for enabling StallGuard DIAG pin to fire

[cdaringe]

Thanks for this lib--it's awesome!

Problem

Flashing the stallguard example works using UART registers, but the DIAG pin does not go hot, yielding perhaps an incomplete SG impl.

Discussion

I'm after UART control, but I want very responsive SG detection. The DIAG pin has a few constraints on when it activates (https://www.analog.com/media/en/technical-documentation/data-sheets/TMC2209_datasheet_rev1.08.pdf). I'm still working through why the pin doesn't rise even when this lib reports a SG state from SGRESULT.

[peterpolidoro]

Interesting, I have not tested the DIAG pin output, but it would be great to figure out how to make this work.

The datasheet says:
DIAG is pulsed by StallGuard when SG_RESULT falls below SGTHRS. It is only enabled in StealthChop
mode, and when TCOOLTHRS ≥ TSTEP > TPWMTHRS

One or more of those conditions must not be true. I will have to experiment with this when I have some time. If you figure it out in the mean time, please let me know!

[cdaringe]

I have a sneaking suspicion there may be something conflicting also with the enable pin. On my board, the enable pin shares a trace with the diagnostic pin, only because I have it slammed into a breadboard :-) Sent from Gmail Mobile

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On Mon, Mar 11, 2024 at 10:31 AM Peter Polidoro ***@***.***> wrote: Interesting, I have not tested the DIAG pin output, but it would be great to figure out how to make this work. The datasheet says: DIAG is pulsed by StallGuard when SG_RESULT falls below SGTHRS. It is only enabled in StealthChop mode, and when TCOOLTHRS ≥ TSTEP > TPWMTHRS One or more of those conditions must not be true. I will have to experiment with this when I have some time. If you figure it out in the mean time, please let me know! — Reply to this email directly, view it on GitHub <#58 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAHU57IQSXWWD3ILJ3HOS2TYXXZ6FAVCNFSM6AAAAABEPDTSCKVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTSOBZGAZTAMRQGU> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[cdaringe]

My TSTEP & TCOOLTHRS were within a percent of one another. I put a >=1% gap on them, and it triggers now. 😄 . Interesting that SW detection could trigger but not HW. Who knows, maybe weird analog digital conversion malarkey.