HD64F2168 Datasheet, PDF (231/874 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer

8.3 Port 3
Port 3 is an 8-bit I/O port. Port 3 pins also function as a bidirectional data bus, wake-up event
input pins. Port 3 functions change according to the operating mode. Port 3 has the following
registers.
• Port 3 data direction register (P3DDR)
• Port 3 data register (P3DR)
• Port 3 pull-up MOS control register (P3PCR)
8.3.1 Port 3 Data Direction Register (P3DDR)
The individual bits of P3DDR specify input or output for the pins of port 3.
Bit Bit Name Initial Value R/W Description
7
P37DDR 0
W In normal extended mode:
6
P36DDR 0
W Bidirectional data bus
5
P35DDR 0
4
P34DDR 0
3
P33DDR 0
2
P32DDR 0
W In other mode:
W ^{The corresponding port 3 pins are output ports when}
W
the P3DDR bits are set to 1, and input ports when
cleared to 0.
W
1
P31DDR 0
W
0
P30DDR 0
W
8.3.2 Port 3 Data Register (P3DR)
P3DR stores output data for the port 3 pins.
Bit Bit Name Initial Value R/W Description
7
P37DR
0
R/W In normal extended mode (ADMXE = 0):
6
P36DR
0
5
P35DR
0
4
P34DR
0
3
P33DR
0
2
P32DR
0
1
P31DR
0
0
P30DR
0
R/W If a port 3 read is performed while the P3DDR bits are
R/W
set to 1, the P3DR values are read. When the P3DDR
bits are cleared to 0, 1 is read.
R/W _{In other mode:}
R/W _{If a port 3 read is performed while the P3DDR bits are}
R/W set to 1, the P3DR values are read. If a port 3 read is
R/W ^{performed while the P3DDR bits are cleared to 0, the}
pin states are read.
R/W
Rev. 3.00, 03/04, page 191 of 830