Renesas M16C/6NK Laptop User Manual


 
Rev.1.10 Jul 01, 2005 page 130 of 318
REJ09B0124-0110
M16C/6N Group (M16C/6NK, M16C/6NM) 14. Serial I/O
Under development
This document is under development and its contents are subject to change.
Figure 14.3 UART2 Block Diagram
RXD2
1 / (n2+1)
1/16
1/16
1/2
U2BRG
register
Clock synchronous type
(when internal clock is selected)
Clock synchronous
type
Clock synchronous type
(when internal clock is selected)
Clock synchronous type
(when external clock is selected)
CLK2
Clock source selection
f1SIO or f2SIO
f8SIO
f32SIO
Internal
External
RTS2
CTS2
TXD2
(UART2)
CLK
polarity
reversing
circuit
CLK1 to CLK0
00
01
10
CKDIR
CKPOL
UART reception
UART transmission
Clock synchronous
type
CKDIR
1
0
RXD polarity reversing
circuit
0
1
VSS
0
1
SMD2 to SMD0
010, 100, 101, 110
001
010, 100, 101, 110
001
0
1
CRS
CRD
CTS2 /
RTS2
n2: Values set to the U2BRG register
PCLK1: Bit in PCLKR register
SMD2 to SMD0, CKDIR: Bits in U2MR register
CLK1 to CLK0, CKPOL, CRD, CRS: Bits in U2C0 register
CTS/RTS disabled
CTS/RTS disabled
CTS/RTS selected
Reception
control circuit
Transmission
control circuit
Receive
clock
Transmit
clock
TXD
polarity
reversing
circuit
(1)
Transmit/
receive
unit
PCLK1
f1SIO or f2SIO
1/2
Main clock, PLL clock, or on-chip oscillator clock
1/2
1/8
f8SIO
f32SIO
f1SIO
f2SIO
0
1
1/4