SN8P26L38
8-Bit Micro-Controller
SONiX TECHNOLOGY CO., LTD
Page 80
Version 1.5
7.4
I/O OPEN-DRAIN REGISTER
P1.0/P1.1/P3.2/P3.3/P5.0/P5.1/P5.2 built in open-drain function. P1.0/P1.1/P3.2/P3.3/P5.0/P5.1/P5.2 must be set as
output mode when enable open-drain function. Open-drain external circuit is as following.
U
M CU2
U
VCC
Open-drain pin
Open-drain pin
M CU1
Pull -up Resistor
The pull-up resistor is necessary. Open-drain output high is driven by pull-up resistor. Output low is sunken by MCU
’s
pin.
0E9H
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
P1OC
P52OC
P51OC
P50OC
P33OC
P32OC
-
P11OC
P10OC
Read/Write
W
W
W
W
W
-
W
W
After reset
0
0
0
0
0
-
0
0
Bit 0
P10OC:
P1.0 open-drain control bit
0 = Disable open-drain mode
1 = Enable open-drain mode
Bit 1
P11OC:
P1.1 open-drain control bit
0 = Disable open-drain mode
1 = Enable open-drain mode
Bit 3
P32OC:
P3.2 open-drain control bit
0 = Disable open-drain mode
1 = Enable open-drain mode
Bit 4
P33OC:
P3.3 open-drain control bit
0 = Disable open-drain mode
1 = Enable open-drain mode
Bit 5
P50OC:
P5.0 open-drain control bit
0 = Disable open-drain mode
1 = Enable open-drain mode
Bit 6
P51OC:
P5.1 open-drain control bit
0 = Disable open-drain mode
1 = Enable open-drain mode
Bit 7
P52OC:
P5.2 open-drain control bit
0 = Disable open-drain mode
1 = Enable open-drain mode