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Merge pull request #5977 from prplz/bitbang-i2c

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Bitbang i2c: switch scl to input for reading
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Dan Halbert 2022-02-03 18:34:49 -05:00 committed by GitHub
commit a39f0cfede
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2
shared-module/bitbangio/I2C.c
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@ -49,9 +49,11 @@ STATIC void scl_release(bitbangio_i2c_obj_t *self) {
uint32_t count = self->us_timeout; uint32_t count = self->us_timeout;
delay(self); delay(self);
// For clock stretching, wait for the SCL pin to be released, with timeout. // For clock stretching, wait for the SCL pin to be released, with timeout.
common_hal_digitalio_digitalinout_switch_to_input(&self->scl, PULL_UP);
for (; !common_hal_digitalio_digitalinout_get_value(&self->scl) && count; --count) { for (; !common_hal_digitalio_digitalinout_get_value(&self->scl) && count; --count) {
common_hal_mcu_delay_us(1); common_hal_mcu_delay_us(1);
} }
common_hal_digitalio_digitalinout_switch_to_output(&self->scl, true, DRIVE_MODE_OPEN_DRAIN);
// raise exception on timeout // raise exception on timeout
if (count == 0) { if (count == 0) {
mp_raise_msg(&mp_type_TimeoutError, translate("Clock stretch too long")); mp_raise_msg(&mp_type_TimeoutError, translate("Clock stretch too long"));