Greg,

here's another report of level triggering solving the issue: https://community.nxp.com/thread/456907

Can you please give that a try? I.e. change line 77 to:

gpio_set_intr_type((gpio_num_t)m_intpin, GPIO_INTR_LOW_LEVEL);

I'll also get a DB9 plug to implement Marks test solution.

Regards,
Michael

Am 14.01.2018 um 17:52 schrieb Michael Balzer:

Hmmmm, I think level triggered interrupt would help here.

We currently let the interrupt trigger on the negative edge (line 77). Maybe GPIO_INTR_LOW_LEVEL can help?

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