The start bit is detected in the following steps.
- The falling edge of the RxD pin is detected.
- When the falling edge of the RxD pin is detected, the ｔransmit/receive clock gets activated.
- The level of the RxD pin is checked again on the rising edge of the ｔransmit/receive clock.
- If the level is "L", it will be determined as the start bit.
If it is "H", reception will not be performed by the determination as noise. Also, the reception interrupt request bit or error flags will not be set.
When a RTS is output, the output of the RTS pin becomes "H" once, when detecting the falling edge of the RxD pin in the Step 1. However, if the level of the RxD pin is "H" on the rising edge of the ｔransmit/receive clock in the Step 3, the output of the RTS pin returns to "L".
|M16C/6NK, M16C/6NL, M16C/6NM, M16C/6NN|