r5f21346mnfp Renesas Electronics Corporation., r5f21346mnfp Datasheet - Page 483

• Manufacturer Part Number: r5f21346mnfp
• Description: Single-chip Mcus Incorporates The R8c Cpu Core
• Manufacturer: Renesas Electronics Corporation.

R8C/34M Group
R01UH0131EJ0100 Rev.1.00
Jun 21, 2011
23. Serial Interface (UART2)
The serial interface consists of three channels, UART0 to UART2. This chapter describes the UART2.
23.1
Figure 23.1
CTS2/RTS2
UART2 has a dedicated timer to generate a transfer clock.
Figure 23.1 shows a UART2 Block Diagram. Figure 23.2 shows a Block Diagram of UART2 Transmit/Receive
Unit. Table 23.1 lists the Pin Configuration of UART2.
UART2 has the following modes:
• Clock synchronous serial I/O mode
• Clock asynchronous serial I/O mode (UART mode)
• Special mode 1 (I
• Multiprocessor communication function
RXD2
SMD2 to SMD0, CKDIR: Bits in U2MR register
CLK1, CLK0, CKPOL, CRD, CRS: Bits in U2C0 register
DF2EN: Bit in URXDF register
CLK2
f32
Clock source selection
fC
f1
f8
Overview
= 00b
= 01b
= 10b
= 11b
CLK1 to CLK0
switching
CKPOL
polarity
CTS/RTS selected
circuit
UART2 Block Diagram
CLK
CKDIR
= 1
CKDIR
= 0
CRS = 0
2
Digital filter
C mode)
CRS = 1
CKDIR
internal
CKDIR
external
Clock synchronous type
(internal clock selected)
switching circuit
CTS/RTS disabled
RXD polarity
1/(n+1)
U2BRG
register
CRD = 0
CRD = 1
VSS
DF2EN = 1
DF2EN = 0
CTS/RTS disabled
1/16
1/16
1/2
Clock synchronous type
(external clock selected)
Clock synchronous type
(internal clock selected)
Clock synchronous type
Clock synchronous type
= 010b, 100b, 101b, 110b
UART reception
UART transmission
= 100b, 101b, 110b
= 001b, 010b
n: Setting value in U2BRG register
CKDIR = 0
CKDIR = 1
= 001b
RTS2
CTS2
SMD2 to SMD0
control circuit
Transmission
control circuit
Reception
Receive
clock
Transmit
clock
23. Serial Interface (UART2)
Transmit/
receive
unit
Page 451 of 740
switching
polarity
circuit
TXD
TXD2