Clock Synchronous Serial I/O Mode - Renesas M16C Series User Manual

M30240 Group
UART transmit/receive control register 2
b7 b6 b5 b4 b3
0
Figure 1.80: Serial I/O-related registers (5)

1.2.23.1 Clock synchronous serial I/O mode

The clock synchronous serial I/O mode uses a transfer clock to transmit and receive data. Figure 1.81
shows the UARTi transmit/receive mode register. Table 1.25 lists the specifications of the clock syn-
chronous serial I/O mode.
Figure 1.81: UARTi transmit/receive mode register in clock synchronous serial I/O mode
Rev.1.00 Sep 24, 2003 Page 85 of 360
b2 b1 b0
Symbol
UCON
Bit
Bit name
symbol
U0IRS UART0 transmit
interrupt cause select bit
U1IRS UART1 transmit
interrupt cause select bit
U0RRM UART0 continuous
receive mode enable bit
U1RRM UART1 continuous
receive mode enable bit
CLKMD0 CLK/CLKS select bit 0
CLKMD1 CLK/CLKS select
bit 1 (Note)
Reserved
Nothing is assigned.
This bit can neither be set nor reset. When read, its content is indeterminate.
Note: When using multiple pins to output the transfer clock, the following requirements must be met:
• UART1 internal/external clock select bit (bit 3 at address 03A8
UARTi transmit/receive mode registers
b7 b6 b5 b4 b3 b2 b1 b0
Symbol
0 0 0 1
UiMR(i=0,1)
Bit symbol
SMD0
Serial I/O mode select bit
SMD1
SMD2
CKDIR
STPS
PRY
PRYE
SLEP
UART2 transmit/receive mode register
b7 b6 b5 b4 b3 b2 b1 b0
Symbol
0
0 0 1
U2MR
Bit symbol
SMD0
Serial I/O mode select bit
SMD1
SMD2
CKDIR
STPS
PRY
PRYE
IOPOL
Note 1: Usually set to "0".
Address When reset
03B0 X0000000
16 2
Function
(During clock synchronous
serial I/O mode)
0 : Transmit buffer empty (Tl = 1) 0 : Transmit buffer empty (Tl = 1)
1 : Transmission completed 1 : Transmission completed
(TXEPT = 1)
0 : Transmit buffer empty (Tl = 1) 0 : Transmit buffer empty (Tl = 1)
1 : Transmission completed 1 : Transmission completed
(TXEPT = 1)
0 : Continuous receive Invalid
mode disabled
1 : Continuous receive
mode enable
0 : Continuous receive Invalid
mode disabled
1 : Continuous receive
mode enabled
Valid when bit 5 = "1" Invalid
0 : Clock output to CLK1
1 : Clock output to CLKS1
0 : Normal mode
Must always be "0"
(CLK output is CLK1 only)
1 : Transfer clock output
from multiple pins
function selected
Must always be "0"
Must always be "0"
Address
03A0 , 03A8
16 16
Bit name Function
b2 b1 b0
0 0 1 : Clock synchronous serial
I/O mode
Internal/external clock 0 : Internal clock
select bit 1 : External clock
Invalid in clock synchronous serial I/O mode
0 (Must always be "0" in clock synchronous serial I/O mode)
Address
0378
16
Bit name Function
b2 b1 b0
0 0 1 : Clock synchronous serial
I/O mode
Internal/external clock 0 : Internal clock
select bit 1 : External clock
Invalid in clock synchronous serial I/O mode
TxD, RxD I/O polarity 0 : No reverse
reverse bit (Note) 1 : Reverse
UART0 to UART2
Function
R W
(During UART mode)
(TXEPT = 1)
(TXEPT = 1)
) = "0".
16
When reset
00
16
R W
When reset
00
16
R W