
3. Port structures
MC97F6108A User’s manual
20
DATA
REGISTER
SUB-FUNC DATA OUTPUT
SUB-FUNC ENABLE
DIRECTION
REGISTER
SUB-FUNC DIRECTION
SUB-FUNC DATA INPUT
PORTx INPUT
PAD
VDD
VDD
MUX
MUX
0
1
MUX
1
0
0
1
Schmitt Level
Input
VDD
Level Shift (1.8V to ExtVDD)
Level Shift (ExtVDD to 1.8V)
OPEN-DRAIN
REGISTER
PULL-UP
REGISTER
VDD
* If one sub-function is selected, the direction of the sub-function is applied to the port automatically.
example)
EIENAB = 0x01
→
P02 input mode
T3CR1 = 0x02
→
P05 output mode
Figure 5. Secondary Function I/O Port