150
Table 8-9 Port 4 Pin Functions
Pin
Pin Functions and Selection Method
P4
0
/SCK
32
The pin function depends on bit CKE1 and CKE0 in SCR3-2, bit COM32 in
SMR32, and bit PCR4
0
in PCR4.
CKE1
0
1
CKE0
0
1
*
COM32
0
1
*
*
PCR4
0
0
1
*
*
Pin function
P4
0
input pin
P4
0
output pin
SCK
32
SCK
32
output pin
input pin
8.4.4
Pin States
Table 8-10 shows the port 4 pin states in each operating mode.
Table 8-10 Port 4 Pin States
Pins
Reset
Sleep
Subsleep
Standby
Watch
Subactive
Active
P4
3
/
IRQ
0
High-
Retains
Retains
High-
Retains
Functional
Functional
P4
2
/TXD
32
impedance
previous previous impedance
previous
P4
1
/RXD
32
state
state
state
P4
0
/SCK
32