Changes between Version 28 and Version 29 of gpio

Timestamp:

12/15/2021 10:37:04 PM (3 years ago)

Author:

Tim Harvey

Comment:

clarify the behavior of gpioset

gpio

@@ -314 +314 @@
  - **gpiomon** - wait for events on GPIO lines, specify which events to watch, how many events to process before exiting or if the events should be reported to the console
 
-On Ubuntu {{{libgpiod}}} and its apps can be isntalled via the {{{gpiod}}} package:
+On Ubuntu {{{libgpiod}}} and its apps can be installed via the {{{gpiod}}} package:
 {{{#!bash
 apt install gpiod
 }}}
+
+Note that {{{gpioset}}} (and all libgpiod apps) will revert the state of a GPIO line back to its original value when it exits. For this reason if you want the state to persist you need to instruct {{{gpioset}}} to wait for a signal and optionally detach and run in the background.
 
 Examples:
@@ -326 +328 @@
 # gpioget gpiochip3 7
 1
-# gpioset gpiochip 3 7=0
-# gpioget gpiochip3 7
-0
-}}}
+# gpioset --mode=signal --background gpiochip 3 7=0
+}}}
+  - Note that once gpioset exits its process the GPIO's it changed will revert back to their prior state (by design) therefor we run it above with {{{--mode=signal}}} telling it to continue to run into it receives a signal and (optinally) {{{--background}}} telling it to detach from the controlling terminal to give our shell back.
  - Newport
 {{{#!bash