h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 289

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

8.10.2
Table 8.19 summarizes the port 9 registers.
Table 8.19 Port 9 Registers
Notes: 1. Lower 16 bits of the address.
Port 9 Data Direction Register (P9DDR)
P9DDR is an 8-bit write-only register, the individual bits of which specify input or output for the
pins of port 9. P9DDR cannot be read; if it is, an undefined value will be returned.
P9DDR is initialized to H'40 (mode 1) or H'00 (modes 2 and 3) by a reset and in hardware standby
mode. It retains its prior state in software standby mode.
Name
Port 9 data direction register
Port 9 data register
Mode 1
Modes 2 and 3
Bit
Initial value
Read/Write
Initial value
Read/Write
Modes 1, 2, and 3 (EXPE = 1)
Pin P97 functions as a bus control input (WAIT), the IIC0 I/O pin (SDA0), or an I/O port,
according to the wait mode setting. When P97 functions as an I/O port, it becomes an output
port when P97DDR is set to 1, and an input port when P97DDR is cleared to 0.
Pin P96 functions as the output pin when P96DDR is set to 1, and as the subclock input
(EXCL) or an input port when P96DDR is cleared to 0.
Pins P95 to P93 automatically become bus control outputs (AS/IOS, WR, RD), regardless of
the input/output direction indicated by P95DDR to P93DDR.
Pins P92 and P90 become output ports when P92DDR and P90DDR are set to 1, and input
ports when P92DDR and P91DDR are cleared to 0.
2. Initial value depends on the mode.
Register Configuration
P97DDR P96DDR P95DDR P94DDR P93DDR P92DDR P91DDR P90DDR
W
W
7
0
0
W
W
6
1
0
Abbreviation
P9DDR
P9DR
W
W
5
0
0
W
W
4
0
0
R/W
W
R/W
Rev. 4.00 Jun 06, 2006 page 235 of 1004
W
W
3
0
0
Initial Value
H'40/H'00 *
H'00
W
W
2
0
0
2
Section 8 I/O Ports
REJ09B0301-0400
Address *
H'FFC0
H'FFC1
W
W
1
0
0
1
W
W
0
0
0