UPD78F1502AGK-GAK-AX Datasheet, PDF (546/1031 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcontrollers

78K0R/Lx3
CHAPTER 14 SERIAL ARRAY UNIT
Figure 14-73. Flowchart of UART Transmission (in Single-Transmission Mode)
Starting UART communication
Setting SAU1EN and SAU0EN
bits of PER0 register to 1
Setting transfer rate by
SPSm register
SMRmn, SCRmn: Setting communication
SDRmn[15:9]:
Setting transfer rate
SOLmn:
Setting output data level
SOm, SOEm:
Setting output
Perform initial setting when SEmn = 0.
Port manipulation
Writing 1 to SSmn bit
Writing transmit data to
TXDq (=SDRmn[7:0])
Transfer end interrupt
No
generated?
Yes
Transmission completed?
No
Yes
Writing 1 to STmn bit
Clearing SAU1EN and SAU0EN
bits of PER0 register to 0
End of communication
Caution After setting the SAUmEN to 1, be sure to set the SPSm register after 4 or more clocks have
elapsed.
R01UH0004EJ0501 Rev.5.01
530
Jun 20, 2011