djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Merge pull request #5977 from prplz/bitbang-i2c

Browse Source 
Bitbang i2c: switch scl to input for reading
This commit is contained in:
Dan Halbert 2022-02-03 18:34:49 -05:00 committed by GitHub
commit a39f0cfede
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
shared-module/bitbangio/I2C.c
View File

@ -49,9 +49,11 @@ STATIC void scl_release(bitbangio_i2c_obj_t *self) {
uint32_t count = self->us_timeout;
delay(self);
// 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) {
common_hal_mcu_delay_us(1);
}
common_hal_digitalio_digitalinout_switch_to_output(&self->scl, true, DRIVE_MODE_OPEN_DRAIN);
// raise exception on timeout
if (count == 0) {
mp_raise_msg(&mp_type_TimeoutError, translate("Clock stretch too long"));