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Specifications in this manual are tentative and subject to change
Clock-Synchronous Serial I/O
Mitsubishi microcomputers
M30240 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Figure 2.46: Set-up procedure of transmission in clock-synchronous serial I/O mode (1)
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Internal/external clock select bit
0 : Internal clock
Setting UARTi transmit/receive mode register (i=0 to 2)
UART0 transmit/receive mode register
U0MR
[Address 03A016]
UART1 transmit/receive mode register
U1MR
[Address 03A816]
Invalid in clock synchronous I/O mode
Must be fixed to “001”
b7
b0
01
00
0
Invalid in clock synchronous I/O mode
Sleep select bit
Must be “0” in clock synchronous I/O mode
Internal/external clock select bit
0 : Internal clock
UART2 transmit/receive mode register
U2MR
[Address 037816]
Invalid in clock synchronous I/O mode
Must be fixed to “001”
b7
b0
01
00
0
Invalid in clock synchronous I/O mode
TXD, R XD I/O polarity reverse bit
Usually set to “0”
Setting UARTi transmit/receive control register 0 (i=0 to 2)
UART0 transmit/receive control register 0
U0C0 [Address 03A4 16]
UART1 transmit/receive control register 0
U1C0 [Address 03AC 16]
CLK polarity select bit
0 : Transmission data is output at falling
edge of transfer clock and reception data is
input at rising edge
BRG count source select bit
0 0 : f 1 is selected
0 1 : f 8 is selected
1 0 : f 32 is selected
1 1 : Inhibited
b1 b0
CTS/RTS function select bit
(Valid when bit 4 = “0”)
0 : CTS function is selected (Note)
CTS/RTS disable bit
0 : CTS/RTS function enabled
Transmit register empty flag
0 : Data present in transmit register
(during transmission)
1 : No data present in transmit register
(transmission completed)
Transfer format select bit
0 : LSB first
Note: Set the corresponding port direction register to “0” .
b7
b0
00
0 0
UART2 transmit/receive control register 0
U2C0 [Address 037C16]
CLK polarity select bit
0 : Transmission data is output at falling
edge of transfer clock and reception data
is input at rising edge
b7
b0
00
CTS/RTS disable bit
0 : CTS/RTS function enabled
Transfer format select bit
0 : LSB first
BRG count source select bit
0 0 : f 1 is selected
0 1 : f 8 is selected
1 0 : f 32 is selected
1 1 : Inhibited
b1 b0
CTS/RTS function select bit
(Valid when bit 4 = “0”)
0 : CTS function is selected (Note)
Transmit register empty flag
0 : Data present in transmit register
(during transmission)
1 : No data present in transmit register
(transmission completed)
UART transmit/receive control register 2
UCON [Address 03B0 16]
UART0 transmit interrupt cause select bit
0 : Transmit buffer empty (Tl = 1)
CLK/CLKS select bit 1
0 : Normal mode (CLK output is CLK1 only)
UART1 transmit interrupt cause select bit
0 : Transmit buffer empty (Tl = 1)
Valid when bit 5 = “1”
Setting UART transmit/receive control register 2 and UART2 transmit/receive control register 1
UART2 transmit/receive control register 1
U2C1 [Address 037D 16]
UART2 transmit interrupt cause select bit
0 : Transmit buffer empty (Tl = 1)
Error signal output enable bit
Must be “0” in clock synchronous I/O
mode
Data logic select bit
0 : No reverse
b7
b0
00
b7
b0
00
Reserved
Must always be "0"
0