User’s Manual U16898EJ3V0UD
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CHAPTER 11 SERIAL INTERFACE UART6
11.1 Functions of Serial Interface UART6
Serial interface UART6 has the following two modes.
(1) Operation stop mode
This mode is used when serial communication is not executed and can enable a reduction in the power
consumption.
For details, see
11.4.1 Operation stop mode
.
(2) Asynchronous serial interface (UART) mode
This mode supports the LIN (Local Interconnect Network)-bus. The functions of this mode are outlined below.
For details, see
11.4.2 Asynchronous serial interface (UART) mode
and
11.4.3 Dedicated baud rate
generator
.
•
Two-pin
configuration T
X
D6: Transmit data output pin
R
X
D6: Receive data input pin
•
Data length of communication data can be selected from 7 or 8 bits.
•
Dedicated internal 8-bit baud rate generator allowing any baud rate to be set
•
Transmission and reception can be performed independently.
•
MSB- or LSB-first communication selectable
•
Inverted transmission operation
•
Synchronous break field transmission from 13 to 20 bits
•
More than 11 bits can be identified for synchronous break field reception (SBF reception flag provided).
Cautions 1. The T
X
D6 output inversion function inverts only the transmission side and not the reception
side. To use this function, the reception side must be ready for reception of inverted data.
2. If clock supply to serial interface UART6 is not stopped (e.g., in the HALT mode), normal
operation continues. If clock supply to serial interface UART6 is stopped (e.g., in the STOP
mode), each register stops operating, and holds the value immediately before clock supply
was stopped. The T
X
D6 pin also holds the value immediately before clock supply was
stopped and outputs it. However, the operation is not guaranteed after clock supply is
resumed. Therefore, reset the circuit so that POWER6 = 0, RXE6 = 0, and TXE6 = 0.
3. If data is continuously transmitted, the communication timing from the stop bit to the next
start bit is extended two operating clocks of the macro. However, this does not affect the
result of communication because the reception side initializes the timing when it has
detected a start bit. Do not use the continuous transmission function if the interface is
incorporated in LIN.