RIOT/examples/leds_shell

LEDs and basic GPIO example application

Description

The application leds_shell is a basic example, which allows easy, interactive control of internal board LEDs, and basic GPIO for externally connected simple devices (for e.g. additional LEDs, relay, motors - via dedicated drivers, etc.).

In particular, this example shows:

• on/off and toggle internal board LEDs.
• initialize GPIO port in output mode.
• set GPIO port state to HIGH or LOW.

Shell command

The following commands are available:

• led0, led1 ... led7: allows switching on/off or toggle internal board LEDs. Number of commands depends on internal LEDs number.
• init: call before interact with GPIO port to initialize chosen port in output mode, which allows setting it to HIGH or LOW state.
• set: sets GPIO port state to HIGH.
• clear: sets GPIO port stet to LOW.
• help: default RIOT command, which shows available commands.

Example on native

• Build and run LEDs example application on the native target, as Linux application:

$ make term
[...]
RIOT native interrupts/signals initialized.
RIOT native board initialized.
RIOT native hardware initialization complete.

main(): This is RIOT! (Version: 2021.07-devel-10893-gb2e97-example-leds_shell)
leds_shell, version 1.0.0
>

Or run it directly without terminal. Go to RIOT/examples/leds_shell and run commands:

$ make
[...]
$ ./bin/native/leds_shell.elf
RIOT native interrupts/signals initialized.
RIOT native board initialized.
RIOT native hardware initialization complete.

main(): This is RIOT! (Version: 2021.07-devel-10893-gb2e97-example-leds_shell)
leds_shell, version 1.0.0
>

• List the available commands:

> help
help
Command              Description
---------------------------------------
init                 GPIO pin initialization
set                  Set GPIO pin to HIGH
clear                Set GPIO pin to LOW
led0                 Switch on/off on-board LED0
led1                 Switch on/off on-board LED1

• Enable internal LED0 and LED1 (the native target has two virtual LEDs):

> led0 on
led0 on
LED_RED_ON

> led1 on
led1 on
LED_GREEN_ON

Example on sample board - stm32f469i-disco

• Build and flash leds_shell example application on sample board, for example stm32f469i-disco target, which has 4 internal LEDs:

$ make BOARD=stm32f469i-disco flash term
[...]
main(): This is RIOT! (Version: 2021.07-devel-10894-g2ad22b9-example-leds_shell)
leds_shell, version 1.0.0
> help
help
Command              Description
---------------------------------------
init                 GPIO pin initialization
set                  Set GPIO pin to HIGH
clear                Set GPIO pin to LOW
led0                 Switch on/off on-board LED0
led1                 Switch on/off on-board LED1
led2                 Switch on/off on-board LED2
led3                 Switch on/off on-board LED3

• Switch on/off internal LEDs using commands led0, led1, led2 or led3.