SH7108 Datasheet, PDF (355/560 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

Section 10 Serial Communication Interface (SCI)
Initialization
[1]
Start transmission
Read TDRE flag in SSR
[2]
No
TDRE = 1
Yes
Write transmit data to TDR and
clear TDRE flag in SSR to 0
All data transmitted?
Yes
No
[3]
[1] SCI initialization:
Set the TxD pin using the PFC.
[2] SCI status check and transmit data
write:
Read SSR and check that the TDRE
flag is set to 1, then write transmit data
to TDR and clear the TDRE flag to 0.
[3] Serial transmission continuation
procedure:
To continue serial transmission, be
sure to read 1 from the TDRE flag to
confirm that writing is possible, then
write data to TDR, and then clear the
TDRE flag to 0.
Read TEND flag in SSR
No
TEND = 1
Yes
Clear TE bit in SCR to 0
<End>
Figure 10.17 Sample Serial Transmission Flowchart
Rev.1.00 Sep. 18, 2008 Page 321 of 522
REJ09B0069-0100