69
CHAPTER 5 PERIPHERAL HARDWARE FUNCTIONS
Figure 5-2. Configurations of Ports 0 and 1
Internal bus
8 CSIM
Selector Selector
P01 
output 
latch
Internal 
SCK
SI SCK SOINT4
V
DD
Pull-up 
resistor
P-ch
P00/INT4
P01/SCK
P02/SO/SB0
P03/SI/SB1
Bit 0 of 
POGA
Input buffer Output buffer which can 
be switched to either 
push-pull output or N-ch 
open-drain output
Pull-up 
resistor
V
DD
P-ch
P10/INT0
P11/INT1
P12/INT2
P13/TI0
Bit 1 of 
POGA
Input buffer Φ or f
X
/64
Input buffer with hysteresis
TI0 INT2 INT1 INT0
Noise 
eliminator
Selector
N-ch
open drain