HD64F3670 Datasheet, PDF (118/305 Pages) Renesas Technology Corp – Hitachi Single-Chip Microcomputer

9.2 Port 2
Port 2 is a general I/O port also functioning as a SCI3 I/O pin. Each pin of the port 2 is shown in
figure 9-2. The register settings of PMR1 and SCI3 have priority for functions of the pins for both
uses.
Port 2
P22/TXD
P21/RXD
P20/SCK3
Figure 9-2 Port 2 Pin Configuration
Port 2 has the following registers. For details on register addresses and register states during each
process, refer to appendix B, Internal I/O Registers.
• Port control register 2(PCR2)
• Port data register 2(PDR2)
9.2.1 Port Control Register 2(PCR2)
PCR2 selects inputs/outputs in bit units for pins to be used as general I/O ports of port 2.
Bit Bit Name Initial Value R/W
7−
−
−
6−
−
−
5−
−
−
4−
−
−
3−
−
−
2 PCR22 0
W
1 PCR21 0
W
0 PCR20 0
W
Description
Reserved
When each of the port 2 pins P22 to P20 functions as an
general I/O port, setting a PCR2 bit to 1 makes the
corresponding pin an output port, while clearing the bit to 0
makes the pin an input port.
Rev. 1.0, 03/01, page 94 of 280