SH7046 Datasheet, PDF (404/611 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7046 Series

Section 12 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.
Checking and clearing of the TDRE
flag is automatic when the DTC is
activated by a transmit data empty
interrupt (TXI) request and data is
written to TDR.
Read TEND flag in SSR
No
TEND = 1
Yes
Clear TE bit in SCR to 0
<End>
Figure 12.17 Sample Serial Transmission Flowchart
Rev. 4.00 Dec 05, 2005 page 360 of 564
REJ09B0270-0400