Renesas RL78 Series User Manual page 514

RL78/G1D
13.6.4 Calculating baud rate
(1) Baud rate calculation expression
The baud rate for UART (UART0 and UART1) communication can be calculated by the following expressions.
(Baud rate) = {Operation clock (f
Caution Setting serial data register mn (SDRmn) SDRmn[15:9] = (0000000B, 0000001B) is prohibited.
Remarks 1.
2.
The operation clock (f
mode register mn (SMRmn).
R01UH0515EJ0120 Rev.1.20
Dec 16, 2016
) frequency of target channel} ÷ (SDRmn[15:9] + 1) ÷ 2 [bps]
MCK
When UART is used, the value of SDRmn[15:9] is the value of bits 15 to 9 of the SDRmn register
(0000010B to 1111111B) and therefore is 2 to 127.
m: Unit number (m = 0, 1), n: Channel number (n = 0 to 3), mn = 00 to 03, 10 to 13
) is determined by serial clock select register m (SPSm) and bit 15 (CKSmn) of serial
MCK
CHAPTER 13 SERIAL ARRAY UNIT
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