SH7713 Datasheet, PDF (605/904 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series

Section 16 Serial Communication Interface with FIFO (SCIF)
Start of transmission
Read TDFE bit in SCFSR
No
TDFE = 1?
Yes
Write (16 – transmit trigger
set number) bytes of transmit
data to SCFTDR, read 1
from TDFE bit and TEND flag
in SCFSR, then clear to 0
No
All data transmitted?
Yes
Read TEND bit in SCFSR
No
TEND = 1?
Yes
No
Break output?
Yes
Clear port DR to 0
Clear TE bit in SCSCR to 0
Specify TxD pin as output port
by PFC
1. SCIF status check and transmit data write:
Read the serial status register (SCFSR)
and check that the TDFE flag is set to 1,
then write transmit data to SCFTDR, read 1
from the TDFE and TEND flags, then clear
these flags to 0.
The number of data bytes 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 bit to 0.
3. Break output at the end of serial
transmission:
To output a break in serial transmission,
clear the port data register (DR) to 0 before
clearing the TE bit in SCSCR to 0, and then
specify the TxD pin as an output port by the
PFC.
In steps 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 16.4 Sample Serial Transmission Flowchart
Rev.1.50 Aug. 30, 2006 Page 565 of 860
REJ09B0288-0150