Renesas RL78/G13 - Page 669

RL78/G13 CHAPTER 12 SERIAL ARRAY UNIT
R01UH0146EJ0100 Rev.1.00 650
Sep 22, 2011
Figure 12-84. Flowchart of UART Transmission (in Continuous Transmission Mode)
Starting UART communication
Writing 1 to the SSmn bit
Writing transmit data to
TXDq (=SDRmn[7:0])
Writing 1 to the STmn bit
SMRmn, SCRmn: Setting communication
SDRmn[15:9]: Setting transfer rate
SOLmn: Setting output data level
SOm, SOEm: Setting output
N
o
N
o
N
o
Y
es
Setting the SAUmEN bit of the
PER0 register to 1
Setting operation clock by
the SPSm register
Port manipulation
End of communication
Clearing 0 to the MDmn0 bit
Y
es
TSFmn = 1?
T
r
ansfer end interrupt
generated?
N
o
Y
es
N
o
Communication continued?
Y
es
Y
es
Clearing the SAUmEN bit of the
PER0 register to 0
Transmitting next data?
<2>
<3>
Buffer empty interrupt
generated?
Writing 1 to the MDmn0 bit
<4>
<5>
S
pec
if
y t
h
e
i
n
i
t
i
a
l
sett
i
ngs w
hil
e t
h
e
SEmn bit of serial channel enable status
register m (SEm) is 0 (operation is
stopped).
<1>
Select the buffer empty interrupt.
<6>
Remark <1> to <6> in the figure correspond to <1> to <6> in Figure 12-83 Timing Chart of UART
Transmission (in Continuous Transmission Mode).