open-ameba/RTL00_SDKV35a/example_sources/gpio_level_irq/readme.txt

22 lines
823 B
Text
Raw Normal View History

2016-12-14 01:21:37 +00:00
Example Description
This example describes how to implement high/low level trigger on 1 gpio pin.
Pin name PC_4 and PC_5 map to GPIOC_4 and GPIOC_5:
Connect PC_4 and PC_5
- PC_4 as gpio input high/low level trigger.
- PC_5 as gpio output
In this example, PC_5 is signal source that change level to high and low periodically.
PC_4 setup to listen low level events in initial.
When PC_4 catch low level events, it disable the irq to avoid receiving duplicate events.
(NOTE: the level events will keep invoked if level keeps in same level)
Then PC_4 is configured to listen high level events and enable irq.
As PC_4 catches high level events, it changes back to listen low level events.
Thus PC_4 can handle both high/low level events.
In this example, you will see log that prints high/low level event periodically.