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lib/io/hyped_i2c/src/lib.rs

@@ -26,6 +26,8 @@ pub trait HypedI2c {
 }
 
 #[macro_export]
+/// Macro to write a byte to a register on an I2C device or return an error.
+/// Does nothing if the write is successful, otherwise returns the error type specified.
 macro_rules! i2c_write_or_err {
     ($i2c:expr, $device_address:expr, $register_address:expr, $data:expr, $err_type:ty) => {
         match $i2c.write_byte_to_register($device_address, $register_address, $data) {