
S1C88409 TECHNICAL MANUAL
EPSON
81
CHAPTER 5: PERIPHERAL CIRCUITS AND OPERATION (I/O Ports)
5.8.5 I/O memory of I/O ports
Table 5.8.5.1 shows the I/O port control bits.
Table 5.8.5.1(a) I/O port control bits
Address
Function
R/W
Init
0
1
Comment
Name
Bit
00FFE0
P07 I/O control register
P06 I/O control register
P05 I/O control register
P04 I/O control register
P03 I/O control register
P02 I/O control register
P01 I/O control register
P00 I/O control register
R/W
0
Input
Output
IOC07
IOC06
IOC05
IOC04
IOC03
IOC02
IOC01
IOC00
D7
D6
D5
D4
D3
D2
D1
D0
00FFE1
P17 I/O control register
P16 I/O control register
P15 I/O control register
P14 I/O control register
P13 I/O control register
P12 I/O control register
P11 I/O control register
P10 I/O control register
R/W
0
Input
Output
IOC17
IOC16
IOC15
IOC14
IOC13
IOC12
IOC11
IOC10
D7
D6
D5
D4
D3
D2
D1
D0
00FFE2
–
P23 I/O control register
P22 I/O control register
P21 I/O control register
P20 I/O control register
–
R/W
–
0
–
Input
–
Output
"0" when being read
–
IOC23
IOC22
IOC21
IOC20
D7
D6
D5
D4
D3
D2
D1
D0
00FFE3
P37 I/O control register
P36 I/O control register
P35 I/O control register
P34 I/O control register
P33 I/O control register
P32 I/O control register
P31 I/O control register
P30 I/O control register
R/W
0
Input
Output
IOC37
IOC36
IOC35
IOC34
IOC33
IOC32
IOC31
IOC30
D7
D6
D5
D4
D3
D2
D1
D0
00FFE4
P07 I/O port data register
P06 I/O port data register
P05 I/O port data register
P04 I/O port data register
P03 I/O port data register
P02 I/O port data register
P01 I/O port data register
P00 I/O port data register
R/W
1
Low
High
P07D
P06D
P05D
P04D
P03D
P02D
P01D
P00D
D7
D6
D5
D4
D3
D2
D1
D0
00FFE5
P17 I/O port data register
P16 I/O port data register
P15 I/O port data register
P14 I/O port data register
P13 I/O port data register
P12 I/O port data register
P11 I/O port data register
P10 I/O port data register
R/W
1
Low
High
P17D
P16D
P15D
P14D
P13D
P12D
P11D
P10D
D7
D6
D5
D4
D3
D2
D1
D0