I have a good experience of the real(/critical)time world, but I'm new with Arduino. I noticed that Serial.write is synchronous. If the buffer size is >64 (the USART size) it lasts the time of the physical transmission minus 64char. It is obvious with simple tests as : Serial.write (char64) comes back in 1 millisec if the USART buffeur is empty and comes back in 64*10/baudrate if USART buffer is full. Does anyone has written an asynchronous Serial.write? If not who can help me to write it? That is to say have the docs on the USART, the interrupts and soon? Basically, the point is to fill the buffer, get an interrupt when it is free to fill it again.
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