h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 265

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

8.4.3
Modes 1, 2, and 3 (EXPE = 1): In modes 1, 2, and 3 (when EXPE = 1), port 3 pins automatically
function as data I/O pins. The port 3 pin functions are shown in figure 8.10.
Modes 2 and 3 (EXPE = 0): In modes 2 and 3 (when EXPE = 0), port 3 functions as host
interface data bus I/O pins (HDB7 to HDB0) or as I/O ports. When the HI12E bit is set to 1 in
SYSCR2 and a transition is made to slave mode, port 3 functions as the host interface data bus. In
slave mode, P3DR and P3DDR should be cleared to H'00. When the HI12E bit is cleared to 0, port
3 functions as an I/O port, and input or output can be specified on a bit-by-bit basis. When a bit in
P3DDR is set to 1, the corresponding pin functions as an output port, and when cleared to 0, as an
input port.
The port 3 pin functions are shown in figure 8.11.
Pin Functions in Each Mode
Figure 8.10 Port 3 Pin Functions (Modes 1, 2, and 3 (EXPE = 1))
Figure 8.11 Port 3 Pin Functions (Modes 2 and 3 (EXPE = 0))
Port 3
Port 3
P37 (I/O)/HDB7 (I/O)
P36 (I/O)/HDB6 (I/O)
P35 (I/O)/HDB5 (I/O)
P34 (I/O)/HDB4 (I/O)
P33 (I/O)/HDB3 (I/O)
P32 (I/O)/HDB2 (I/O)
P31 (I/O)/HDB1 (I/O)
P30 (I/O)/HDB0 (I/O)
D7 (I/O)
D6 (I/O)
D5 (I/O)
D4 (I/O)
D3 (I/O)
D2 (I/O)
D1 (I/O)
D0 (I/O)
Rev. 4.00 Jun 06, 2006 page 211 of 1004
Section 8 I/O Ports
REJ09B0301-0400