Datasheet
RL78/L12    CHAPTER 12 SERIAL ARRAY UNIT 
R01UH0330EJ0200 Rev.2.00      485 
Dec 13, 2013 
(4)  Processing flow (in continuous transmission mode) 
Figure 12-80. Timing Chart of UART Transmission (in Continuous Transmission Mode) 
SSmn
SEmn
SDRmn
TxDq pin
INTSTq
TSFmn
P
ST ST
P
ST
P
SP
BFFmn
<1>
<2> <2><3>
Note
<2>
<3>
<5>
<6>
<3>
<4>
MDmn0
STm n
SP
SP
Transmit data 1 Transmit data 2
Transmit data 3
Shift
register mn
Transmit data 1
Transmit data 2
Transmit data 3
Shift operationShift operation
Shift operation
Data transmission
Data transmission
Data transmission
Note  If transmit data is written to the SDRmn register while the BFFmn bit of serial status register mn (SSRmn) is 
1 (valid data is stored in serial data register mn (SDRmn)), the transmit data is overwritten. 
Caution  The MDmn0 bit of serial mode register mn (SSRmn) can be rewritten even during operation. 
  However, rewrite it before transfer of the last bit is started, so that it will be rewritten before the 
transfer end interrupt of the last transmit data. 
Remark  m: Unit number (m = 0), n: Channel number (n = 0), q: UART number (q = 0) 
  mn = 00 










