diff --git a/ports/raspberrypi/common-hal/audiobusio/PDMIn.c b/ports/raspberrypi/common-hal/audiobusio/PDMIn.c index 327bec8de72..b436469d090 100644 --- a/ports/raspberrypi/common-hal/audiobusio/PDMIn.c +++ b/ports/raspberrypi/common-hal/audiobusio/PDMIn.c @@ -43,7 +43,7 @@ void common_hal_audiobusio_pdmin_construct(audiobusio_pdmin_obj_t *self, // Use the state machine to manage pins. common_hal_rp2pio_statemachine_construct(&self->state_machine, pdmin, MP_ARRAY_SIZE(pdmin), - sample_rate * 32 * 2, // Frequency based on sample rate + sample_rate * OVERSAMPLING * 2, // Frequency based on sample rate NULL, 0, NULL, 0, // may_exec NULL, 1, PIO_PINMASK32_NONE, PIO_PINMASK32_ALL, // out pin @@ -64,7 +64,8 @@ void common_hal_audiobusio_pdmin_construct(audiobusio_pdmin_obj_t *self, PIO_FIFO_TYPE_DEFAULT, PIO_MOV_STATUS_DEFAULT, PIO_MOV_N_DEFAULT); uint32_t actual_frequency = common_hal_rp2pio_statemachine_get_frequency(&self->state_machine); - if (actual_frequency < MIN_MIC_CLOCK) { + if (actual_frequency < 2 * MIN_MIC_CLOCK) { // 2 PIO samples per audio clock + common_hal_audiobusio_pdmin_deinit(self); mp_raise_ValueError(MP_ERROR_TEXT("sampling rate out of range")); }