RL78/G13 CHAPTER 12 SERIAL ARRAY UNIT
R01UH0146EJ0100 Rev.1.00 584
Sep 22, 2011
Figure 12-31. Flowchart of Master Transmission (in Single-Transmission Mode)
Starting CSI communication
Write STmn bit to 1
Transmission completed?
No
Yes
Clear SAUmEN bit of the
PER0 register to 0.
End of communication
Writing transmit data to
SIOp (=SDRmn[7:0])
When Transfer end interrupt is generated, it
moves to interrupt processing routine
Setting transmit data
For the initial setting, refer to Figure 12-27.
(Select Transfer end interrupt)
SAU default setting
Wait for transmit completes
Transfer end interrupt
Enables interrupt
Clear interrupt request flag (XXIF), reset interrupt mask (XXMK) and set
interrupt enable (EI).
Disable interrupt (MASK)
Set data for transmission and the number of data. Clear communication end flag
(Storage area, Transmission data pointer, Number of communication data and
Communication end flag are optionally set on the internal RAM by the software)
Check completion of transmission by
verifying transmit end flag
Writing to SIOp makes SOp and
SCKp signals out
(communication starts)
Read transmit data from storage area and write it
to SIOp. Update transmit data pointer.
Read transmit data, if any, from storage area and
write it to SIOp. Update transmit data pointer.
If not, set transmit end flag
Main routine
Main routine
Interrupt processing routine
Transmitting next data?
Writing transmit data to
SIOp (=SDRmn[7:0])
No
Sets communication
completion flag
RETI
Yes
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