GMS84512 Datasheet, PDF (26/123 Pages) Hynix Semiconductor – 8-BIT SINGLE CHIP MICROCOMPUTER

GMS 84512 / 84524
3.1 PORT
There are 6-ports in this device.
You can use these ports an digital I/O or 2nd function I/O
3.1.1 R0 PORT
8-bit I/O port including direction register and port data register (IOA Type)
l Register Structure and Description
Register Name
Symbol R/W Address
R0 I/O Direction Register
R0 PORT Data Register
R0DD
R0
W
R/W
00C1_H
00C0_H
Initial Value
0000 0000
Not initialized
R0 PORT I/O DIRECTION REGISTER
R0DD
<00C1_H>
W
W
W
W
W
W
W
W
7
6
5
4
3
2
1
0
R0DD7 R0DD6 R0DD5 R0DD4 R0DD3 R0DD2 R0DD1 R0DD0
Initial Value when RESET
[ 0000 0000 ]
Assign the direction of R0 port
(R0DD0) is assigned to R00 port)
0 : Input
1 : Output
R0 PORT DATA REGISTER
R0
<00C0_H>
R/W
7
R/W
6
R/W
5
R/W
4
R/W
3
R/W
2
R/W
1
R/W
0
R07 R06 R05 R04 R03 R02 R01 R00
Initial Value when RESET
[Not initialized ]
Port R0 output data
If output mode port is read, the read data is R0 register data. And if input mode port is read, the
read data is R0 pin data.
3- 1