Datasheet

Table Of Contents
Section 9 I/O Ports
Page 244 of 846 REJ09B0140-0900 Rev. 9.00
Sep 16, 2010
H8S/2215 Group
9.4 Port 7
Port 7 is a 5-bit I/O port also functioning as bus control output, manual reset input, and 8-bit timer
I/O. Port 7 has the following registers.
Port 7 data direction register (P7DDR)
Port 7 data register (P7DR)
Port 7 register (PORT7)
9.4.1 Port 7 Data Direction Register (P7DDR)
P7DDR is an 8-bit write-only register, the individual bits of which specify input or output for the
pins of port 7. P7DDR cannot be read; if it is, an undefined value will be read. Since this is a
write-only register, bit manipulation instructions should not be used to write to it. For details, see
section 2.9.4, Accessing Registers Containing Write-Only Bits.
Bit Bit Name Initial Value R/W Description
7 to
5
— Undefined Reserved
These bits are undefined and cannot be modified.
4 P74DDR 0 W
3 P73DDR 0 W
2 P72DDR 0 W
1 P71DDR 0 W
Setting a P7DDR bit to 1 makes the corresponding port 7
pin an output pin, while clearing the bit to 0 makes the pin
an input pin.
0 P70DDR 0 W