GMS81508A Datasheet, PDF (60/91 Pages) Hynix Semiconductor – USERS MANUAL

R6 PORT I/O DIRECTION REGISTER
R6DD
<00CD_H>
W
W
W
W
7
6
5
4
3
2
1
0
R6DD7 R6DD6 R6DD5 R6DD4 R6DD3 R6DD2 R6DD1 R6DD0
Determines I/O of R6 port
0 : Input
1 : Output

R6 PORT DATA REGISTER
R6
<00CC_H>
R/W R/W R/W R/W
R
R
R
R
7
6
5
4
3
2
1
0
R47 R46 R45 R44 R43 R42 R41 R40
GMS81508/16
Port R6 output data
On the initial RESET, R60 can’t be used digital input port, because this port is
selected as an analog input port by ADCM register. To use this port as a digital I/O
port, change the value of lower 4 bits of ADCM(address 0E8H). On the other
hand,R6 port, all eight pins can not be used as digital I/O port simultaneously. At
least one pin is used as an analog input.

UNUSED PORTS
All unused ports should be set properly that current flow through port doesn't exist.
First consider the setting the port as an input mode. Be sure that there is no
current flow after considering its relationship with external circuit. In input mode,
the pin impedance viewing from external MCU is very high that the current doesn’t
flow.
But input voltage level should be V_SS or V_DD. Be careful that if unspecified voltage,
i.e. if unfirmed level voltage is applied to input pin, there can be little current ( max.
1mA at 2V) flow.
If it is not appropriate to set as an input mode, then set to output mode considering
there is no current flow. Setting to High or Low is decided considering its
relationship with external circuit. For example, if there is external pull-up resistor
then it is set to output mode, i.e. to High, and if there is external pull-down register,
it is set to low.
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