Renesas RL78 Series User Manual page 487

RL78/G1D
13.6 Operation of UART (UART0, UART1) Communication
This is a start-stop synchronization function using two lines: serial/data transmission (T
(R D) lines. By using these two communication lines, each data frame, which consist of a start bit, data, parity bit, and
X
stop bit, is transferred asynchronously (using the internal baud rate) between the microcontroller and the other
communication party. Full-duplex asynchronous communication UART communication can be performed by using a
channel dedicated to transmission (even-numbered channel) and a channel dedicated to reception (odd-numbered
channel). The LIN-bus can be implemented by using UART2 with an external interrupt (INTP0).
[Data transmission/reception]
● Data length of 7, 8, or 9 bits
● Select the MSB/LSB first
● Level setting of transmit/receive data (selecting whether to reverse the level)
● Parity bit appending and parity check functions
● Stop bit appending, stop bit check function
[Interrupt function]
● Transfer end interrupt/buffer empty interrupt
● Error interrupt in case of framing error, parity error, or overrun error
[Error detection flag]
● Framing error, parity error, or overrun error
In addition, UART0 reception (by the following channels) supports the SNOOZE mode. When RxD0 pin input is
detected while in the STOP mode, the SNOOZE mode makes data reception that does not require the CPU possible.
Only UART0 can be specified for the reception baud rate adjustment function.
UART0 uses channels 0 and 1 of SAU0.
UART1 uses channels 2 and 3 of SAU0.
Note Only UART0 can be specified for the 9-bit data length.
Unit Channel
0
1
Note It is dedicated for communication between the MCU and RF transceiver.
R01UH0515EJ0120 Rev.1.20
Dec 16, 2016
Note
Used as CSI
0 CSI00
1 –
2 –
3 –
0 CSI20
Note
1 CSI21
CHAPTER 13 SERIAL ARRAY UNIT
D) and serial/data reception
X
Used as Simplified I
Used as UART
UART0
UART1
–
2
C
IIC00
–
–
–
IIC20
–
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