SH7763 Datasheet, PDF (1235/2026 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC Engine Family SH-4A Series

Section 28 Serial Communication Interface with FIFO/IrDA Interface (SCIF/IrDA)
In serial transmission, the SCIF operates as described below.
1. When data is written into SCFTDR, the SCIF transfers the data from SCFTDR to SCTSR and
starts transmitting. Confirm that the TDFE flag in SCFSR is set to 1 before writing transmit
data to SCFTDR. The number of data bytes that can be written is at least 16 (transmit trigger
setting).
2. When data is transferred from SCFTDR to SCTSR and transmission is started, consecutive
transmit operations are performed until there is no transmit data left in SCFTDR. When the
number of transmit data bytes in SCFTDR falls to or below the transmit trigger number set in
SCFCR, the TDFE flag is set. If the TIE bit in SCSCR is set to 1 at this time, a transmit-FIFO-
data-empty interrupt (TXI) request is generated.
When the external clock is selected, data is output in synchronization with the input clock.
The serial transmit data is sent from the SCIF_TXD pin in the LSB-first order.
3. The SCIF checks the SCFTDR transmit data at the timing for sending the last bit. If data is
present, the data is transferred from SCFTDR to SCTSR, and then serial transmission of the
next frame is started. If there is no transmit data, the TEND flag in SCFSR is set to 1 after the
last bit is sent, and the transmit data pin (SCIF_TXD pin) retains the output state of the last bit.
4. After serial transmission ends, the CLK pin is fixed high.
Figure 28.15 shows an example of the operation for transmission in clocked synchronous mode.
Synchronization clock
SCIF_SCK
Serial data
SCIF_TXD
TDFE flag
LSB
Bit 0 Bit 1
MSB
Bit 7 Bit 0 Bit 1
Bit 6 Bit 7
TEND flag
TXI interrupt Data written to SCFTDR TXI interrupt
request and TDFE flag cleared to 0 request
by TXI interrupt handler
One frame
Figure 28.15 Sample SCIF Transmission Operation in Clocked Synchronous Mode
Rev. 1.00 Oct. 01, 2007 Page 1169 of 1956
REJ09B0256-0100