Rev. 1.0, 02/00, page 198 of 1141
10.4
Port 2
10.4.1
Overview
Port 2 is an 8-bit I/O port. Table 10.8 shows the port 2 configuration.
Port 2 consists of pins that are used both as standard I/O ports (P27 to P20) and SCI clock I/O
(SCK1), receive data input (SI1), send data output (SO1), I
2
C bus interface clock I/O (SCL0,
SCL1), or data I/O (SDA0, SDA1). It is switched by serial mode register (SMR), serial control
register (SCR), and port control register 2 (PCR2).
Port 2 can select the MOS pull-up function.
Table 10.8
Port 2 Configuration
Port
Function
Alternative Function
P27 (standard I/O port)
SYNCI (Formatless serial clock input)
P26 (standard I/O port)
SCL0 (I
2
C bus interface clock I/O)
P25 (standard I/O port)
SDA0 (I
2
C bus interface data I/O)
P24 (standard I/O port)
SCL1 (I
2
C bus interface clock I/O)
P23 (standard I/O port)
SDA1 (I
2
C bus interface data I/O)
P22 (standard I/O port)
SCK1 (SCI1 clock I/O)
P21 (standard I/O port)
SO1 (SCI1 transmit data output)
Port 2
P20 (standard I/O port)
SI1 (SCI1 receive data input)
10.4.2
Register Configuration
Table 10.9 shows the port 2 register configuration.
Table 10.9
Port 2 Register Configuration
Name
Abbrev.
R/W
Size
Initial Value
Address
*
Port control register 2
PCR2
W
Byte
H'00
H'FFD2
Port data register 2
PDR2
R/W
Byte
H'00
H'FFC2
MOS pull-up select
register 2
PUR2
R/W
Byte
H'00
H'FFE2
Note:
*
Lower 16 bits of the address.