HD64F2149 Datasheet, PDF (253/1035 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

8.6.3 Pin Functions
Port 5 pins also function as SCI0 I/O pins (TxD0, RxD0, SCK0) and the IIC0 I/O pin (SCL0). The
port 5 pin functions are shown in table 8.11.
Table 8.11 Port 5 Pin Functions
Pin
P52/SCK0/SCL0
Selection Method and Pin Functions
The pin function is switched as shown below according to the combination of
bits CKE1 and CKE0 in SCR of SCI0, bit C/A in SMR of SCI0, bit ICE in ICCR
of IIC0, and bit P52DDR.
ICE
0
1
CKE1
0
1
0
C/A
0
1
—
0
CKE0
0
1
—
—
0
P52DDR
0
1
—
—
—
—
Pin function P52
P52
SCK0 SCK0 SCK0 SCL0
input pin output pin output pin output pin input pin I/O pin
When this pin is used as the SCL0 I/O pin, bits CKE1 and CKE0 in SCR of
SCI0 and bit C/A in SMR of SCI0 must all be cleared to 0.
SCL0 is an NMOS open-drain output, and has direct bus drive capability.
When set as the P52 output pin or SCK0 output pin, this pin is an NMOS push-
pull output.
P51/RxD0
The pin function is switched as shown below according to the combination of
bit RE in SCR of SCI0 and bit P51DDR.
RE
0
1
P51DDR
0
1
—
Pin function P51 input pin
P51 output pin
RxD0 input pin
P50/TxD0
The pin function is switched as shown below according to the combination of
bit TE in SCR of SCI0 and bit P50DDR.
TE
0
1
P50DDR
0
1
—
Pin function P50 input pin
P50 output pin
TxD0 output pin
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