CHAPTER 12 PORT FUNCTIONS
573
User’s Manual U15195EJ5V0UD
(2) Setting of I/O mode and control mode
The port DH mode register (PMDH) is used to set the I/O mode of port DH and the port DH mode control
register (PMCDH) is used to set the operation in control mode.
(a) Port DH mode register (PMDH)
This register can be read or written in 8-bit or 1-bit units.
7
1
PMDH
6
1
5
PMDH5
4
PMDH4
3
PMDH3
2
PMDH2
1
PMDH1
0
PMDH0
Address
FFFFF026H
After reset
FFH
Bit position
Bit name
Function
5 to 0
PMDHn
(n = 5 to 0)
Specifies input/output mode of PDHn pin.
0: Output mode (output buffer on)
1: Input mode (output buffer off)
(b) Port DH mode control register (PMCDH)
This register can be read or written in 8-bit or 1-bit units.
Caution Set bits 7 and 6 as follows.
Operation Mode
Bit 7
Bit 6
Single-chip mode
0
0
ROMless mode
1
1
7
PMCDH7
PMCDH
6
PMCDH6
5
PMCDH5
4
PMCDH4
3
PMCDH3
2
PMCDH2
1
PMCDH1
0
PMCDH0
Address
FFFFF046H
After reset
Note
00H/FFH
Note
00H: Single-chip mode
FFH: ROMless mode
Bit position
Bit name
Function
5 to 0
PMCDHn
(n = 5 to 0)
Specifies operation mode of PDHn pin
0: I/O port mode
1: A21 to A16 output mode