LE910Cx HW User Guide
1VV0301298 Rev. 33
Page 85 of 128
2021-06-29
Not Subject to NDA
8.7.1.
Using a GPIO Pad as Input
GPIO pads, when used as inputs, can be connected to a digital output of another device
and report its status, provided that this device has interface levels compatible with the
1.8V CMOS levels of the GPIO.
If the digital output of the device is connected to the GPIO input, the pad has interface
levels other than 1.8V CMOS. It can be buffered with an open collector transistor with a
10 k
Ω
pull-up resistor to 1.8V.
8.7.2.
Using a GPIO Pad as an interrupt / Wakeup source
GPIO pads used as inputs can also be used as an interrupt source for software. In general,
all GPIO pads can also be used as an interrupt. However, not all GPIO’s can be used as a
wakeup source of the module (wakeup from sleep).
Only the following GPIO’s can be used for waking up the system from sleep:
•
GPIO1
•
GPIO4
•
GPIO5
•
GPIO8
8.7.3.
Using a GPIO Pad as Output
The GPIO pads, when used as outputs, can drive 1.8V CMOS digital devices or compatible
hardware. When set as outputs, the pads have a push-pull output, and therefore the pull-
up resistor can be omitted.
Figure 24: GPIO Output Pad Equivalent Circuit