SN32F760 Series
32-Bit Cortex-M0 Micro-Controller
SONiX TECHNOLOGY CO., LTD
Page 78
Version 2.0
5.3.12 GPIO Port n Open-Drain Control register (GPIOn_ODCTRL) (n=0,1,2,3)
Address offset: 0x2C
Several I/Os have built-in open-drain function and must be set as output mode when enable open-drain function.
Open-drain external circuit is as following.
U
MCU2
U
VCC
Open-drain pin
Open-drain pin
MCU1
Pull-up Resistor
The external pull-up resistor is necessary. The digital output function of I/O only supports sink current capability, so the
open-drain output high is driven by pull-
up resistor, and output low is sunken by MCU’s pin.
Note:
1. VCC shall be less than or equal to VDD of MCU1 and MCU2.
2. Only P0, P1, and P3 support Open-drain.
Bit
Name
Description
Attribute
Reset
31:16
Reserved
R
0
15:0
OC[15:0]
Open-drain control bit (x = 0 to 15)
0: Disable.
1: Enable open-drain function of Pn.x. HW also set Pn.x as output mode
automatically.
W/R
0
