HD6413008VF25 Datasheet, PDF (410/688 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

12. Serial Communication Interface
Initialize
(1)
Start transmitting
Read TDRE flag in SSR
(2)
TDRE = 1
No
Yes
Write transmit data in TDR
and set MPBT bit in SSR
Clear TDRE flag to 0
All data transmitted?
Yes
No
(3)
(1) SCI initialization:
the transmit data output function of
the TxD pin is selected automatically.
(2) SCI status check and transmit data
write:
read SSR, check that the TDRE flag is
1, then write transmit data in TDR.
Also set the MPBT flag to 0 or 1 in
SSR. Finally, clear the TDRE flag to 0.
(3) To continue transmitting serial data:
after checking that the TDRE flag is 1,
indicating that data can be written,
write data in TDR, then clear the TDRE
flag to 0.
(4) To output a break signal at the end of
serial transmission:
set the DDR bit to 1 and clear the DR
bit to 0, then clear the TE bit to 0 in
SCR.
Read TEND flag in SSR
TEND = 1
Yes
Output break signal?
No
No
(4)
Yes
Clear DR bit to 0 and set DDR to 1
Clear TE bit to 0 in SCR
<End>
Figure 12.10 Sample Flowchart for Transmitting Multiprocessor Serial Data
Rev.4.00 Aug. 20, 2007 Page 364 of 638
REJ09B0395-0400