m37905 Renesas Electronics Corporation., m37905 Datasheet - Page 302

• Manufacturer Part Number: m37905
• Description: Mitsubishi 16-bit Single-chip Microcomputer 7700 Family / 7900 Series
• Manufacturer: Renesas Electronics Corporation.

Fig. 11.4.9 Example of transmit timing when transfer data length = 9 bits (when parity disabled,
interrupt request bit
Transmit enable bit
Transmit register
Transmit buffer
UARTi transmit
Transfer clock
empty flag
empty flag
T
TxD
ENDi
2 stop bits selected, CTS function not selected)
The above timing diagram applies when
the following conditions are satisfied:
i
Parity disabled
2 stop bits
CTS function not selected
Cleared to “0” when interrupt request is accepted or cleared to “0” by software.
ST
Data is set in UARTi transmit buffer register.
D
0
D
1
D
2
D
3
Tc
D
7905 Group User’s Manual Rev.1.0
4
T
D
ENDi
5
11.4 Clock asynchronous serial I/O (UART) mode
D
: Next transmit conditions are examined when this signal level
f
EXT
6
becomes “H.”
(T
Tc = 16 (n + 1)/f
the external.)
f
n: Value set in BRGi
ENDi
i
D
: BRGi count source frequency (internal clock)
: BRGi count source frequency (external clock)
7
UARTi transmit register
is an internal signal. Accordingly, it cannot be read from
D
8
SP
SP
i
or 16 (n + 1)/f
ST
D
0
D
EXT
1
D
UARTi transmit buffer register
2
Stopped because transmit enable bit = “0”
D
3
D
4
D
5
D
6
D
7
D
8
SP SP
SERIAL I/O
D
0
to D
ST: Start bit
ST: Stop bit
P: Parity bit
7
: Transfer data
ST
D
0
D
1
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