GMS81508A Datasheet, PDF (55/91 Pages) Hynix Semiconductor – USERS MANUAL

HYUNDAI MicroElectronics
PIN
R10/A0
R11/A1
R12/A2
R13/A3
R14/A4
R15/A5
R16/A6
R17/A7
Single Chip Mode
I/O
I/O
I/O Programmable I/O Port
I/O
I/O
I/O
I/O
I/O
Microprocessor Mode
O
O
O low 8bit address of External Memory
O for CPU.
O
O
O
O
3.3. R2 PORT
R2 Port is composed of 8-bit programmable I/O pin.
Register Name
R2 I/O Direction Register
R2 PORT Data Register
Symbol
R2DD
R2
R/W
W
R/W
Address
00C5_H
00C4_H
Initial Value
0000 0000
Not initialized

R2 PORT I/O DIRECTION REGISTER
R2DD
<00C5_H>
W
W
W
W
W
W
W
W
7
6
5
4
3
2
1
0
R2DD7 R2DD6 R2DD5 R2DD4 R2DD3 R2DD2 R2DD1 R2DD0

R2 PORT DATA REGISTER
Determines I/O of R2 port
0 : Input
1 : Output
R2
<00C4_H>
R/W R/W R/W R/W R/W R/W R/W R/W
7
6
5
4
3
2
1
0
R27 R26 R25 R24 R23 R22 R21 R20
Port R2 output data
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