h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 274

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 8 I/O Ports
8.6.3
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 8.12.
Table 8.12 Port 5 Pin Functions
Pin
P52/SCK0/SCL0
P51/RxD0
P50/TxD0
Rev. 4.00 Jun 06, 2006 page 220 of 1004
REJ09B0301-0400
Pin Functions
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.
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.
In the H8S/2138 Group, when set as the P52 output pin or SCK0 output pin,
this pin is an NMOS push-pull output.
The pin function is switched as shown below according to the combination of
bit RE in SCR of SCI0 and bit P51DDR.
The pin function is switched as shown below according to the combination of
bit TE in SCR of SCI0 and bit P50DDR.
ICE
CKE1
C/A
CKE0
P52DDR
Pin function
RE
P51DDR
Pin function
TE
P50DDR
Pin function
input pin
P52
P51 input pin
P50 input pin
0
0
0
0
output pin
P52
0
1
0
0
0
output pin
SCK0
P51 output pin
P50 output pin
—
0
1
1
1
output pin
SCK0
—
—
1
input pin
SCK0
TxD0 output pin
RxD0 input pin
—
—
—
1
—
—
1
1
I/O pin
SCL0
—
1
0
0
0