M16C62_M Datasheet, PDF (386/615 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/60 SERIES

Clock-Synchronous Serial I/O
Example of wiring
Microcomputer
CLKi
RXDi
RTSi
Mitsubishi microcomputers
M16C / 62A Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Transmitter side IC
CLK
TXD
Port
Example of operation
Receive enable ^{“1”}
bit (RE)
“0”
(1) Reception enabled
(2) Start reception
(3) Reception is complete
(4) Read of reception data
Transmit enable ^{“1”}
bit (TE)
“0”
Transmit buffer ^{“1”}
empty flag (Tl) _{“0”}
“H”
RTSi
“L”
CLKi
RxDi
Receive complete ^{“1”}
flag (Rl)
“0”
Dummy data is set in UARTi transmit buffer register
Transferred from UARTi transmit buffer register to UARTi transmit register
1 / fEXT
Reception data is taken in
D0 D1 D2 D3 D4 D5 D6 D7
D0 D1 D2 D3 D4 D5
Transferred from UARTi receive register
to UARTi receive buffer register
Read out from UARTi receive buffer register
Receive interrupt ^{“1”}
request bit (IR) _{“0”}
Cleared to “0” when interrupt request is accepted, or cleared by software
Shown in ( ) are bit symbols.
The above timing applies to the following settings:
• External clock is selected.
• RTS function is selected.
• CLK polarity select bit = “0”.
fEXT: frequency of external clock
Make sure that the following conditions are met when
the CLKi pin input =“H” before data reception
• Transmit enable bit → “1”
• Receive enable bit → “1”
• Dummy data write to UARTi transmit buffer register
Figure 2.4.13. Operation timing of reception in clock-synchronous serial I/O mode
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