M16C65 Datasheet, PDF (561/829 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M16C/60

Under development
M16C/65 Group
Preliminary Specification
This is a preliminary specification and is subject to change.
23. Serial Interface UARTi (i = 0 to 2, 5 to 7)
23.3.2.6 CTS/RTS Function
The CTS function is used to start transmit operation when a low-level signal is applied to the CTSi/
RTSi (i = 0 to 2, 5 to 7) pin. Transmit operation begins when input to the CTSi/RTSi pin becomes low.
If the low-level signal is switched to high during a transmit operation, the operation stops after the
ongoing transmit/receive operation is completed.
When the RTS function is used, the CTSi/RTSi pin outputs a low-level signal when the MCU is ready
to receive. The output level goes high when a start bit is detected.
Refer to Table 23.10 “I/O Pin Functions in UART Mode”.
23.3.2.7 CTS/RTS Separate Function (UART0)
This function separates CTS0 and RTS0, outputs RTS0 from the P6_0 pin, and inputs CTS0 from the
P6_4 pin. To use this function, set the register bits as shown below.
• The CRD bit in the U0C0 register= 0 (enable CTS/RTS of UART0)
• The CRS bit in the U0C0 register= 1 (output RTS of UART0)
• The CRD bit in the U1C0 register= 0 (enable CTS/RTS of UART1)
• The CRS bit in the U1C0 register= 0 (input CTS of UART1)
• The RCSP bit in the UCON register= 1 (inputs CTS0 from the P6_4 pin)
• The CLKMD1 bit in the UCON register= 0 (CLKS1 not used)
Note that when using the CTS/RTS separate function, CTS/RTS of UART1 function cannot be used.
MCU
TXD0 (P6_3)
RXD0 (P6_2)
IC
IN
OUT
RTS0 (P6_0)
CTS0 (P6_4)
CTS
RTS
Figure 23.17 CTS/RTS Separate Function
REJ09B0484-0030 Rev.0.30 Sep 09, 2008
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