m37905 Renesas Electronics Corporation., m37905 Datasheet - Page 292

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

I/O pins in this mode.
11.4 Clock asynchronous serial I/O (UART) mode
Table 11.4.1 lists the performance overview in the UART mode, and Table 11.4.2 lists the functions of
Table 11.4.1 Performance overview in UART mode
Table 11.4.2 Functions of I/O pins in UART mode
Port P1 direction register: address 05
Port P8 direction register: address 14
Internal/External clock select bit: bit 3 at addresses 30
TxD
TxD
TxD
Note: The TxD
TxD
RxD
CLK
CTS
P1
Transfer data
format
Transfer rate
Error detection
4
, P1
0
1
2
i
i
i
i
/P1
/P1
/P8
/
(P1
(P1
(P1
RTS
is selected.
Pin name
5
3
7
3
, P8
3
2
1
switch bit: bit 2 at address AC
switch bit: bit 3 at address AC
switch bit: bit 5 at address AC
, P1
, P1
, P1
i
(P1
0
, P8
7
6
5
, P8
, P8
, P8
i
0
pin outputs “H” level while transmission is not performed after the UARTi’s operating mode
, P1
1
)
Start bit
Character bit (Transfer data)
Parity bit
Stop bit
When selecting internal clock
When selecting external clock
3
2
1
)
)
)
Item
1
,
Serial data output pin
Programmable I/O port pin
Serial data input pin
Programmable I/O
port pin
BRGi’s count source input pin
Programmable I/O port pin
CTS input pin
RTS output pin
Programmable I/O port pin
Functions
16
16
7905 Group User’s Manual Rev.1.0
16
16
16
11.4 Clock asynchronous serial I/O (UART) mode
TxD
TxD
Port P1 or P8 direction register’s corresponding bit = “0”
– (Can be used as a programmable I/O port pin when
performing only transmission.)
Internal/External clock select bit = “1”
Internal/External clock select bit = “0”
See Table 11.2.1.
1 bit
7 bits, 8 bits, or 9 bits
0 bit or 1 bit (Odd or Even can be selected.)
1 bit or 2 bits
BRGi’s output divided by 16
Maximum 312.5 kbps
4 types (overrun, framing, parity, and summing): presence of an
error can be detected only by check of the error sum flag.
0
0
/P1
/P1
16
3
3
, TxD
, TxD
, 38
16
1
1
, and B0
/P1
/P1
7
7
Method of selection
, or TxD
, or TxD
16
Functions
2
2
/P8
/P8
3
3
switch bit = “0.” (Note)
switch bit = “1.”
SERIAL I/O
11-37