Renesas SH7781 User Manual
Page 1110
21. Serial Communication Interface with FIFO (SCIF)
Rev.1.00 Jan. 10, 2008 Page 1080 of 1658
REJ09B0261-0100
Figure 21.10 shows an example of the operation for transmission in asynchronous mode.
1
0
D0
D1
D7
0/1
1
0
D0
D1
D7
0/1
1
1
TDFE
TEND
Serial
data
Start
bit
Data
Parity
bit
Stop
bit
Start
bit
Idle state
(mark state)
Idle state
(mark state)
SCIF_TXD
Data
Parity
bit
Stop
bit
TXI interrupt
request
Data written to SCFTDR
and TDFE read as 1 then
cleared to 0 by TXI
interrupt handler
TXI interrupt
request
One frame
Figure 21.10 Example of SCIF Transmission Operation
(Example with 8-Bit Data, Parity, One Stop Bit)
4. When modem control is enabled, transmission can be stopped and restarted in accordance with
the
SCIF_CTS input value. When SCIF_CTS is set to 1 during transmission, the SCIF goes to
the mark state after transmission of one frame. When
SCIF_CTS is set to 0, the next transmit
data is output starting from the start bit.
Figure 21.11 shows an example of the operation when modem control is used.
Serial data
SCIF_TXD
SCIF_CTS
0
D0
D1
D7 0/1
0
D0
D1
D7 0/1
Drive high before stop bit
Start
bit
Parity
bit
Stop
bit
Start
bit
Figure 21.11 Example of Operation Using Modem Control (
SCIF_CTS)
(Only in Channel 0)