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examples/stm32f4/src/bin/i2c.rs

@@ -30,6 +30,9 @@ async fn main(_spawner: Spawner) -> ! {
         Hertz(100_000),
         Default::default(),
     );
+
+    // I2C bus can freeze if SCL line is shorted or due to a broken device that clock stretches for too long.
+    // TimeoutI2c allows recovering from such errors by throwing `Error::Timeout` after a given delay.
     let mut timeout_i2c = TimeoutI2c::new(&mut i2c, Duration::from_millis(1000));
 
     let mut data = [0u8; 1];