Serial I/O (Clock Synchronous Serial I/O)
149
Mitsubishi microcomputers
M16C / 62P Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
development
Preliminary Specifications Rev.1.0
Specifications in this manual are tentative and subject to change.
Table 1. 18. 2. Registers to Be Used and Settings in Clock Synchronous Serial I/O Mode
Register
Bit
UiTB
(Note3)
0 to 7
Set transmission data
UiRB
(Note3)
0 to 7
Reception data can be read
OER
Overrun error flag
UiBRG
0 to 7
Set a transfer rate
UiMR
(Note3)
SMD2 to SMD0
Set to “001
2
”
CKDIR
Select the internal clock or external clock
IOPOL
Set to “0”
UiC0
CLK1 to CLK0
Select the count source for the UiBRG register
CRS
Select CTS or RTS to use
TXEPT
Transmit register empty flag
CRD
Enable or disable the CTS or RTS function
NCH
Select TxDi pin output mode (Note 2)
CKPOL
Select the transfer clock polarity
UFORM
Select the LSB first or MSB first
UiC1
TE
Set this bit to “1” to enable transmission/reception
TI
Transmit buffer empty flag
RE
Set this bit to “1” to enable reception
RI
Reception complete flag
U2IRS (Note 1)
Select the source of UART2 transmit interrupt
U2RRM (Note 1)
Set this bit to “1” to use continuous receive mode
UiLCH
Set this bit to “1” to use inverted data logic
UiERE
Set to “0”
UiSMR
0 to 7
Set to “0”
UiSMR2
0 to 7
Set to “0”
UiSMR3
0 to 2
Set to “0”
NODC
Select clock output mode
4 to 7
Set to “0”
UiSMR4
0 to 7
Set to “0”
UCON
U0IRS, U1IRS
Select the source of UART0/UART1 transmit interrupt
U0RRM, U1RRM
Set this bit to “1” to use continuous receive mode
CLKMD0
Select the transfer clock output pin when CLKMD1 = 1
CLKMD1
Set this bit to “1” to output UART1 transfer clock from two pins
RCSP
Set this bit to “1” to accept as input the UART0 CTS
0
signal from the P6
4
pin
7
Set to “0”
Note 1: Set the U0C1 and U1C1 register bit 4 and bit 5 to “0”. The U0IRS, U1IRS, U0RRM and U1RRM bits
are in the UCON register.
Note 2: TxD2 pin is N channel open-drain output. Set the U2C0 register's NCH bit to “0”.
Note 3: Not all register bits are described above. Set those bits to “0” when writing to the registers in clock
synchronous serial I/O mode.
i=0 to 2
Function