Renesas M16C Series User Manual page 97

M30240 Group
RxDi
Figure 1.74: Block diagram of UARTi (i=0,1) transmit/receive circuit
RxD2
Figure 1.75: Block diagram of UART2 transmit/receive circuit
Rev.1.00 Sep 24, 2003 Page 79 of 360
Clock
synchronous
PAR
type
1SP
disabled
SP SP
PAR
PAR
2SP UART
enabled
0 0 0 0 0 0
PAR
UART
2SP enabled
SP SP PAR
1SP
PAR Clock
disabled synchronous
type
"0"
No reverse
RxD data
reverse circuit
Reverse
Clock
synchronous type
UART
(7 bits)
UART
Clock
PAR
(8 bits)
synchronous
disabled
1SP
type
SP SP PAR
2SP
PAR UART
UART
enabled
(9 bits)
PAR: Parity bit
0 0 0 0 0 0 0
D
UART
PAR (9 bits)
enabled
UART
2SP
SP SP
PAR
1SP
Clock
PAR
UART
synchronous
disabled
(7 bits)
type
UART
(8 bits)
"0"
Clock
synchronous type
Clock
synchronous type
UART (7 bits)
UART (8 bits)
UARTi receive register
UART (7 bits)
UART (9 bits)
Clock
synchronous type
UART (8 bits)
UART (9 bits)
0
D D D D D D D
8 7 6 5 4 3
MSB/LSB conversion circuit
Data bus low-order bits
MSB/LSB conversion circuit
D D D D D D
D
8 7 6 5 4 3
UART (8 bits)
UART (9 bits)
Clock synchronous
UART (9 bits)
type
UART (7 bits)
UARTi transmit register
UART (7 bits)
UART (8 bits)
SP: Stop bit
Clock synchronous
PAR: Parity bit
type
UART2 receive register
UART(7 bits)
Clock
synchronous type
UART
(8 bits)
UART
(9 bits)
D D D D D D D D
8 7 6 5 4 3 2 1
Logic reverse circuit + MSB/LSB conversion circuit
Data bus high-order bits
Data bus low-order bits
Logic reverse circuit + MSB/LSB conversion circuit
D D D D D D D
7 6 5 4 3 2 1
8
UART
(8 bits)
UART
(9 bits)
Clock
synchronous type
UART(7 bits) UART2 transmit register
Error signal output
No reverse
disable
TxD data
Error signal
reverse circuit
output circuit
Reverse
Error signal output
enable
SP: Stop bit
PAR: Parity bit
UART0 to UART2
UARTi receive
D D
2 1 0 buffer register
Address 03A6
16
Address 03A7
16
Address 03AE
16
Address 03AF
16
D D
UARTi transmit
2 1 0
buffer register
Address 03A2
16
Address 03A3
16
Address 03AA
16
Address 03AB
16
TxDi
UART2 receive
D
0
buffer register
Address 037E
16
Address 037F
16
D
0 UART2 transmit
buffer register
Address 037A 16
Address 037B 16
TxD2