Rev. 1.2
147
C8051T620/1/6/7 & C8051T320/1/2/3
SFR Address = 0xE1
SFR Definition 22.1. XBR0: Port I/O Crossbar Register 0
Bit
7
6
5
4
3
2
1
0
Name
CP1AE
CP1E
CP0AE
CP0E
SYSCKE
SMB0E
SPI0E
URT0E
Type
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset
0
0
0
0
0
0
0
0
Bit
Name
Function
7
CP1AE
Comparator1 Asynchronous Output Enable.
0: Asynchronous CP1 unavailable at Port pin.
1: Asynchronous CP1 routed to Port pin.
6
CP1E
Comparator1 Output Enable.
0: CP1 unavailable at Port pin.
1: CP1 routed to Port pin.
5
CP0AE
Comparator0 Asynchronous Output Enable.
0: Asynchronous CP0 unavailable at Port pin.
1: Asynchronous CP0 routed to Port pin.
4
CP0E
Comparator0 Output Enable.
0: CP0 unavailable at Port pin.
1: CP0 routed to Port pin.
3
SYSCKE
/SYSCLK Output Enable.
The source of this signal is determined by the OUTCLK bit (see SFR Definition 21.1).
0: /SYSCLK unavailable at Port pin.
1: /SYSCLK output routed to Port pin.
2
SMB0E
SMBus I/O Enable.
0: SMBus I/O unavailable at Port pins.
1: SMBus I/O routed to Port pins.
1
SPI0E
SPI I/O Enable.
0: SPI I/O unavailable at Port pins.
1: SPI I/O routed to Port pins. Note that the SPI can be assigned either 3 or 4 GPIO
pins.
0
URT0E
UART I/O Output Enable.
0: UART I/O unavailable at Port pin.
1: UART TX0, RX0 routed to Port pins P0.4 and P0.5.