Renesas rl78 User Manual

Page of 1004
 
RL78/G1A 
 
CHAPTER  12   SERIAL  ARRAY  UNIT 
R01UH0305EJ0200  Rev.2.00 
 
 
464  
Jul 04, 2013 
Figure 12-45.  Flowchart of Master Transmission/Reception (in Single-Transmission/Reception Mode) 
 
Starting CSI communication 
Disable interrupt (MASK)
Transmission/reception 
completed? 
No 
Yes 
End of communication
Read receive data to SIOp 
(=SDRmn[7:0]) 
Writing transmit data to 
SIOp (=SDRmn[7:0]) 
When transfer end interrupt is generated, it 
moves to interrupt processing routine.
 
Wait for transmission/reception 
completes 
For the initial setting, see Figure 12-42.  
(Select transfer end interrupt)
 
SAU default setting
Transfer end interrupt
Read receive data then writes to storage area, update receive 
data pointer
 
 
RETI 
If there are the next data, it continues
Write 1 to STmn bit
Setting 
transmission/reception data
Setting storage data and number of data for transmission/reception data 
(Storage area, Transmission data pointer, Reception data pointer, Number of 
communication data and Communication end flag are optionally set on the 
internal RAM by the software) 
Enables interrupt
Clear interrupt request flag (XXIF), reset interrupt mask (XXMK) and set 
interrupt enable (EI)
 
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.
 
Main
 r
o
u
tine
 
Mai
n
 routine
In
te
rru
p
t p
roc
es
sing
ro
u
tin
e
 
 
Remark  m: Unit number (m = 0, 1), n: Channel number (n = 0 to 3), p: CSI number (p = 00, 01, 10, 11, 20, 21), 
mn = 00 to 03, 10, 11 
 
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