SH7730 Datasheet, PDF (744/1188 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7780 Series

Section 22 Serial Communication Interface with FIFO (SCIF)
(4) Transmitting Serial Data (Asynchronous Mode)
Figure 22.4 shows a sample flowchart for serial transmission.
Use the following procedure for serial data transmission after enabling the SCIF for
transmission.
Start of transmission
Read TDFE flag in SCFSR
No
TDFE = 1?
Yes
Write transmit data in SCFTDR,
[1]
and clear TDFE flag
and TEND flag in SCFSR
All data transmitted?
Yes
No
[2]
Read TEND flag in SCFSR
No
TEND = 1?
Yes
Clear TE bit in SCSCR to 0
[1] 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 and TEND flags to 0.
The quantity of transmit data that can
be written is 16 - (transmit trigger set
number).
[2] Serial transmission continuation
procedure:
To continue serial transmission, read
1 from the TDFE flag to confirm that
writing is possible, then write data to
SCFTDR, and then clear the TDFE
flag to 0.
In [1] and [2], it is possible to ascertain
the number of data bytes that can be
written from the number of transmit data
bytes in SCFTDR indicated by the upper
8 bits of SCFDR.
End of transmission
Figure 22.4 Sample Flowchart for Transmitting Serial Data
Rev. 1.00 Sep. 19, 2007 Page 696 of 1136
REJ09B0359-0100