r8a77850anbg Renesas Electronics Corporation., r8a77850anbg Datasheet - Page 1118

• Manufacturer Part Number: r8a77850anbg
• Description: Renesas 32-bit Risc Microcomputer Superh? Risc Engine Family
• Manufacturer: Renesas Electronics Corporation.

21. Serial Communication Interface with FIFO (SCIF)
(4)
Figure 21.17 shows a sample flowchart for serial transmission.
Use the following procedure for serial data transmission after enabling the SCIF for transmission.
Rev.1.00 Jan. 10, 2008 Page 1088 of 1658
REJ09B0261-0100
Write transmit data to SCFTDR and clear
TDFE and TEND bits in SCFSR to 0
Serial Data Transmission (Clocked Synchronous Mode)
Read TEND flag in SCFSR
Clear TE bit in SCSCR to 0
Read TDFE bit in SCFSR
Start of transmission
All data transmitted?
End of transmission
TEND = 1 ?
Initialization
TDFE = 1 ?
Yes
Yes
Yes
Figure 21.17 Sample Serial Transmission Flowchart
No
No
No
[1]
[2]
[3]
[1]
[2]
[3]
To continue serial transmission, read 1 from the
SCIF initialization:
See Sample SCIF Initialization Flowchart in figure
21.16.
SCIF status check and transmit data write:
Read SCFSR and check that the TDFE flag is set to
1, then write transmit data to SCFTDR, and clear
the TDFE flag to 0. The transition of the TDFE flag
from 0 to 1 can also be identified by a TXI interrupt.
Serial transmission continuation procedure:
TDFE flag to confirm that writing is possible, then
write data to SCFTDR, and then clear the TDFE
flag to 0.