M30218 Datasheet, PDF (94/179 Pages) Mitsubishi Electric Semiconductor – M30218 Group

Clock synchronous serial I/O mode
Mitsubishi microcomputers
M30218 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
UARTi transmit/receive mode register
b7 b6 b5 b4 b3 b2 b1 b0
0
001
Symbol
UiMR(i=0,1)
Address
When reset
03A016, 03A816
0016
Bit symbol
SMD0
SMD1
SMD2
CKDIR
STPS
PRY
PRYE
SLEP
Bit name
Serial I/O mode select bit
Function
b2 b1 b0
0 0 1 : Clock synchronous serial
I/O mode
Internal/external clock
select bit
0 : Internal clock
1 : External clock
Invalid in clock synchronous serial I/O mode
0 (Must always be "0" in clock synchronous serial I/O mode)
RW
Figure GA-6. UARTi transmit/receive mode register in clock synchronous serial I/O mode (i=0,1)
Table GA-2 lists the functions of the input/output pins during clock synchronous serial I/O mode. Note that
for a period from when the UARTi operation mode is selected to when transfer starts, the TxDi pin outputs
a “H”. (If the N-channel open-drain is selected, this pin is in floating state.)
Table GA-2. Input/output pin functions in clock synchronous serial I/O mode (i=0,1)
Pin name
Function
Method of selection
TxDi
(P44, P74)
RxDi
(P45, P75)
Serial data output
Serial data input
(Outputs dummy data when performing reception only)
Port P45, P75 direction register (bits 5 at address 03EA16 and 03EF16)= “0”
(Can be used as an input port when performing transmission only)
CLKi
(P46, P76)
Transfer clock output
Transfer clock input
Internal/external clock select bit (bit 3 at address 03A016, 03A816) = “0”
Internal/external clock select bit (bit 3 at address 03A016, 03A816) = “1”
Port P46, P76 direction register (bits 6 at address 03EA16 and 03EF16) = “0”
CTSi/RTSi
(P47, P77)
CTS input
CTS/RTS disable bit (bit 4 at address 03A416, 03AC16) =“0”
CTS/RTS function select bit (bit 2 at address 03A416, 03AC16) = “0”
Port P47, P77 direction register (bits 7 address 03EA16 and 03EF16) = “0”
RTS output
CTS/RTS disable bit (bit 4 at address 03A416, 03AC16) = “0”
CTS/RTS function select bit (bit 2 at address 03A416, 03AC16) = “1”
Programmable I/O port CTS/RTS disable bit (bit 4 at address 03A416, 03AC16) = “1”
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