SH7058 Datasheet, PDF (550/1130 Pages) Renesas Technology Corp – Renesas SuperHTM RISC engine

Transmitting Serial Data (Synchronous Mode): Figure 15.18 shows a sample flowchart for
transmitting serial data. The procedure is as follows (the steps correspond to the numbers in the
flowchart):
Initialization
Start of transmission
Read TDRE flag in SSR
TDRE = 1?
Yes
Write transmit data in TDR and
clear TDRE flag to 0 in SSR
1
1. SCI initialization: Set the TxD pin function
with the PFC.
2. SCI status check and transmit data write:
Read SSR, check that the TDRE flag is 1,
2 then write transmit data in TDR and clear
the TDRE flag to 0.
3. To continue transmitting serial data: After
No
checking that the TDRE flag is 1, indicating
that data can be written, write data in TDR,
then clear the TDRE flag to 0. When the
DMAC is activated by a transmit-data-empty
interrupt request (TXI) to write data in TDR,
the TDRE flag is checked and cleared
automatically.
All data transmitted?
Yes
Read TEND flag in SSR
TEND = 1?
Yes
Clear TE bit to 0 in SCR
No
3
No
End
Figure 15.18 Sample Flowchart for Serial Transmitting
Rev. 3.0, 09/04, page 509 of 1086