Serial.Write Question

Is Serial.write a blocking or non-blocking call. I can't find it in the API spec. I am just trying to debug some code and I was wondering if the data is just dumped in the queue or if it actually is sent out before control is returned to the program. Any feedback appreciated!


It's blocking until the last character has been written to the tx register.

As said in present version 22 serial output is blocking until the character is sent out. In Arduino version 1.0 (latest beta version) the serial API has be changed, they have added transmit interrupts with a small output buffer so serial output will not be blocking unless the output buffer is filled up and then it will revert to blocking.