HD6417660 RENESAS [Renesas Technology Corp], HD6417660 Datasheet - Page 512

• Manufacturer Part Number: HD6417660
• Description: Renesas 32-Bit RISC Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

4. Transmit/receive when using the Modem Function
Transmit data
TxD
Rev. 1.00, 02/04, page 474 of 804
CTS
When using a modem function, transmission can be stopped and started again according to the
CTS input value. When the CTS is set to 1 during transmission, the data enters a mark state
after transmitting one frame. When CTS is set to 0, the next transmit data is output starting
with a start bit.
Figure 16.10 shows an example of operation for the CTS control.
Serial
data
RDF
FER
Figure 16.9 shows an example of the operation for reception in asynchronous mode.
1
Start
bit
Start
bit
0
0
D0
D0
Figure 16.9 Example of SCIF Receive Operation
(Example with 8-Bit Data, Parity, One Stop Bit)
Transmission stops
when CTS goes high
D1
D1
One frame
Figure 16.10 CTS Control Operation
Data
D6
D7
RXI interrupt
request
Parity
D7
0/1
bit
Parity
bit
0/1
Stop
bit
1
Stop
bit
Start
bit
0
Data read and RDF flag
read as 1 then cleared
to 0 by RXI interrupt
handler
D0
D1
Data
Transmission starts again
when CTS goes low
Start
bit
0
D7
D0
Parity
0/1
bit
D1
ERI interrupt request
generated by receive
error
Stop
bit
1
(mark state)
D6
Idle state
1
D7
0/1