Renesas M16C Series User Manual

UART0 to UART2
M30240 Group
Rev.1.00 Sep 24, 2003 Page 88 of 360
Figure 1.82: Typical transmit/receive timings in clock synchronous serial I/O mode Polarity select function
Stopped pulsing because transfer enable bit = “0”
1 / f EXT
Dummy data is set in UARTi transmit buffer register
Transmit enable
bit (TE)
Transmit buffer
empty flag (Tl)
CLKi
RxDi
Receive complete
flag (Rl)
RTSi
“H”
“L”
“0”
“1”
“0”
“1”
“0”
“1”
Receive enable
bit (RE)
“0”
“1”
Receive data is taken in
Transferred from UARTi transmit buffer register to UARTi transmit register
Read out from UARTi receive buffer register
The above timing applies to the following settings:
• External clock is selected.
• RTS function is selected.
• CLK polarity select bit = “0”.
f EXT : frequency of external clock
Transferred from UARTi receive register
to UARTi receive buffer register
Receive interrupt
request bit (IR)
“0”
“1”
D0 D1 D2
D3
D4
D5 D6
D7
D0 D1 D2
D3
D4 D5
Shown in ( ) are bit symbols.
Meet the following conditions are met when the CLK
input before data reception = “H”
• Transmit enable bit “1”
• Receive enable bit “1”
• Dummy data write to UARTi transmit buffer register
Cleared to “0” when interrupt request is accepted, or cleared by software
D0
D1 D2
D3
D4 D5 D6
D7
D0
D1 D2
D3
D4 D5 D6
D7
D0
D1 D2
D3
D4 D5 D6
D7
Tc
TCLK
Data is set in UARTi transmit buffer register
Tc = TCLK = 2(n + 1) / fi
fi: frequency of BRGi count source (f
1 , f 8 , f 32 )
n: value set to BRGi
Transfer clock
Transmit enable
bit (TE)
Transmit buffer
empty flag (Tl)
CLKi
TxDi
Transmit
register empty
flag (TXEPT)
“H”
“L”
“0”
“1”
“0”
“1”
“0”
“1”
CTSi
The above timing applies to the following settings:
• Internal clock is selected.
• CTS function is selected.
• CLK polarity select bit = “0”.
• Transmit interrupt cause select bit = “0”.
Transmit interrupt
request bit (IR)
“0”
“1”
Stopped pulsing because CTS = “H”
Transferred from UARTi transmit buffer register to UARTi transmit register
Shown in ( ) are bit symbols.
Cleared to “0” when interrupt request is accepted, or cleared by software
Example of transit timing (when internal clock is selected)
Example of receive timing (when external clock is selected)

Renesas M16C Series Specifications

General

Brand	Renesas
Model	M16C Series
Category	Computer Hardware
Language	English