From 61ef52f967365b229efeca1b4524627001981635 Mon Sep 17 00:00:00 2001
From: "Mark A. Yoder" <Mark.A.Yoder@Rose-Hulman.edu>
Date: Fri, 20 Sep 2024 09:18:31 -0400
Subject: [PATCH] Cleaned up beagle101 button events
---
intro/beagle101/blinkLED.rst | 263 ++++++++++++++--------
intro/beagle101/code/blinkInternalLED.sh | 10 +
intro/beagle101/{ => code}/buttonEvent.sh | 0
intro/beagle101/{ => code}/buttonLED.sh | 0
intro/beagle101/code/seqLEDs.py | 21 ++
5 files changed, 195 insertions(+), 99 deletions(-)
create mode 100755 intro/beagle101/code/blinkInternalLED.sh
rename intro/beagle101/{ => code}/buttonEvent.sh (100%)
rename intro/beagle101/{ => code}/buttonLED.sh (100%)
create mode 100755 intro/beagle101/code/seqLEDs.py
diff --git a/intro/beagle101/blinkLED.rst b/intro/beagle101/blinkLED.rst
index eb0f0b97..be04d6f3 100644
--- a/intro/beagle101/blinkLED.rst
+++ b/intro/beagle101/blinkLED.rst
@@ -16,91 +16,93 @@ Here we'll show you how to do just that in three simple steps.
These steps will work for any of the Beagles.
Plug in the Beagle
-*******************
+------------------
For this step you need to get a USB cable and attach your Beagle
to your host computer with it. Where you attached the cable
depends on which Beagle you have. Click on the tab for your board.
-.. tab-set::
+.. tabs::
- .. tab-item:: Black
+ .. group-tab:: Black
.. figure:: figures/image8.jpg
:width: 632px
+ :height: 166px
:align: center
:alt: Tethered Configuration
- Tethered Configuration
+ Tethered Configuration
.. figure:: figures/image9.jpg
:width: 451px
+ :height: 206px
:align: center
:alt: USB Connection to the Board
- Mini USB Connection to the Board as seen from the bottom.
+ Mini USB Connection to the Board as seen from the bottom.
For more details see: :ref:`beagleboneblack-connectivity`
- .. tab-item:: Blue
+ .. group-tab:: Blue
.. figure:: figures/blueconnect.jpg
:width: 451px
:align: center
:alt: USB Connection to the Blue
- Micro USB Connection to the Blue
+ Micro USB Connection to the Blue
- .. tab-item:: AI-64
+ .. group-tab:: AI-64
.. figure:: figures/usb-tethering.jpg
:width: 400px
:align: center
:alt: Tethered Configuration
- Tethered Configuration
+ Tethered Configuration
.. figure:: figures/usb-c-connection.jpg
:width: 400px
:align: center
:alt: USB Connection to the Board
- USB-c Connection to the Board
+ USB-c Connection to the Board
.. figure:: figures/usb-a-connection.jpg
:width: 400px
:align: center
:alt: USB Connection to the PC/Laptop
- USB Connection to the PC/Laptop
+ USB Connection to the PC/Laptop
.. figure:: figures/power-led.jpg
:width: 400px
:align: center
:alt: Board Power LED
- Board Power LED
+ Board Power LED
- For more details see: :ref:`bbai64-quick-start`
+ For more details see: :ref:`connecting-up-your-beaglebone-ai-64`
- .. tab-item:: Play
+ .. group-tab:: Play
.. figure:: figures/tethered-connection.jpg
:width: 1400
:align: center
:alt: Tethering BeaglePlay to PC
- Tethering BeaglePlay to PC
+ Tethering BeaglePlay to PC
For more details see: :ref:`beagleplay-quick-start`
- .. tab-item:: Pocket
+ .. group-tab:: Pocket
.. figure:: figures/11fig-PB-microUSBattach1.jpg
:align: center
:alt: Tethered Configuration
- Micro USB Connection
+ Micro USB Connection
For more details see: :REF:`connecting_up_pocketbeagle`
@@ -110,75 +112,81 @@ heart beat.
The Beagle is now up and running, but you didn't have to
load up Linux. This is because all Beagles
-(except PocketBeagle, see :ref:`flash-latest-image`
-to install an image on the Pocket) have built-in flash memory
+have built-in flash memory
that has the Debian distribution of Linux preinstalled.
-.. _intro-using-vs-code:
-
-Using VS Code
-**************
-
-.. important:: If VS code is not installed on your board please skip this section and refer
- to next section on how to login and run the code via command line.
+.. note::
+ The one exception is the PocketBeagle which has no built-in
+ flash memory. See :ref:`flash-latest-image`
+ to install an image on the Pocket
+
+Login
+-----
+
+Next you login to the Beagle from your host computer.
+Here you have a choice. If you want a graphical approach,
+choose the ``VS Code`` tab. If you want a command line
+and your host is a Mac, take the ``ssh (Mac)`` tab. If you
+are running Linux on your host,
+take the ``ssh (Linux)`` tab. Finally take the
+``putty (Windows)`` tab for command line from Windows.
-Recent Beagles come with the IDE Visual Studio Code (https://code.visualstudio.com/) installed and
-running. To access it, open a web browser on your host computer and browse to: ``192.168.7.2:3000``
-(use ``192.168.6.2:3000`` for the Mac) and you will see something like:
+.. tabs::
-.. figure:: figures/vscode1.png
- :width: 740
- :align: center
+ .. group-tab:: VS Code
-At this point you can either run the scripts via a command line within VS Code, or
-run them by clicking the ``RUN Code`` button.
+ Recent Beagles come with the IDE Visual Studio Code
+ (https://code.visualstudio.com/) installed and
+ running. To access it, open a web browser on
+ your host computer and browse to: ``192.168.7.2:3000``
+ (use ``192.168.6.2:3000`` for the Mac)
+ and you will see something like:
+ .. figure:: figures/vscode1.png
-Running via the command line
-============================
+ At this point you can either run the scripts via a command
+ line within VS Code, or run them by clicking the
+ ``RUN Code`` button.
-Open a terminal window in VS Code by dropping down the ``Terminal`` menu and selecting ``New Terminal``
-(or entering ``Ctrl+```). The terminal window appears at the bottom of the screen as shown below.
-.. figure:: figures/vscode3.png
- :width: 740
- :align: center
+ Running via the command line
-You can now enter commands and see them run as shown below.
+ Open a terminal window in VS Code by dropping down the
+ ``Terminal`` menu and selecting ``New Terminal`` (or entering
+ ``Ctrl+Shift+```). The terminal window appears at the
+ bottom of the screen as shown below.
-.. figure:: figures/vscode4.png
- :width: 740
- :align: center
-
-Running via the ``RUN`` button
-===============================
+ .. figure:: figures/vscode3.png
-Use the file navigator on the left to navigate to ``examples/BeagleBone/Black/blinkInternalLED.sh`` and you will see:
+ You can now enter commands and see them run as shown below.
-.. figure:: figures/vscode2.png
- :width: 740
- :align: center
+ .. figure:: figures/vscode4.png
-This code blinks one of the USR LEDs built into the board. Click on the ``RUN Code`` triangle on the upper right of the
-screen (see red arrow) to run the code. (You could also enter ``Ctrl+Alt+N``) The USR3 LED should now be blinking.
+ Running via the ``RUN`` button
-Click on the ``Stop Code Run`` (``Ctrl+Alt+M``) square to the right of the ``Run Code`` button.
+ Use the file navigator on the left to navigate to
+ ``examples/BeagleBone/Black/blinkInternalLED.sh``
+ and you will see:
-Time to play! Try changing the LED number (on line 10) from 3 to something else. Click the ``Run Code``
-button (no need to save the file, autosave is on by default).
+ .. figure:: figures/vscode2.png
-Try running ``seqLEDs.py``.
+ This code blinks one of the USR LEDs built into the board.
+ Click on the ``RUN Code`` triangle on the upper right of
+ the screen (see red arrow) to run the code. (You could also enter ``Ctrl+Alt+N``)
+ The USR3 LED should now be blinking.
-Using command line
-******************
+ Click on the ``Stop Code Run`` (``Ctrl+Alt+M``) square to the right of the
+ ``Run Code`` button.
-To access the command line and your host is a Mac, take the ``ssh (Mac)`` tab. If you
-are running Linux on your host, take the ``ssh (Linux)`` tab. Finally take the
-``putty (Windows)`` tab for command line from Windows.
+
+
+ Time to play! Try changing the LED number (on line 10) from
+ 3 to something else. Click the ``Run Code`` button (no
+ need to save the file, autosave is on by default).
-.. tab-set::
+ Try running ``seqLEDs.py``.
- .. tab-item:: ssh (Mac)
+ .. group-tab:: ssh (Mac)
If you are running a Mac host, open a terminal widow and run
@@ -188,7 +196,7 @@ are running Linux on your host, take the ``ssh (Linux)`` tab. Finally take the
Use the password ``temppwd``.
- .. tab-item:: ssh (Linux)
+ .. group-tab:: ssh (Linux)
If you are running a Linux host, open a terminal widow and run
@@ -198,7 +206,7 @@ are running Linux on your host, take the ``ssh (Linux)`` tab. Finally take the
Use the password ``temppwd``.
- .. tab-item:: putty (Windows)
+ .. group-tab:: putty (Windows)
If you are running Window you need to run an ``ssh`` client
to connect to the Beagle. I suggest you use ``putty``.
@@ -212,7 +220,7 @@ are running Linux on your host, take the ``ssh (Linux)`` tab. Finally take the
and password ``temppwd``.
Blink an LED
-============
+------------
Once logged in the rest is easy. First:
@@ -233,7 +241,7 @@ internal LEDs.
.. code-block:: shell-session
- bone:~$ cat blinkInternalLED.py
+ bone:~$ cat blinkInternalLED.sh
LED="3"
LEDPATH='/sys/class/leds/beaglebone:green:usr'
@@ -244,14 +252,25 @@ internal LEDs.
echo "0" > ${LEDPATH}${LED}/brightness
sleep 0.5
done
- bone:~$ ./blinkInternalLED.py
+ bone:~$ ./blinkInternalLED.sh
^c
+:download:`blinkInternalLED.sh<code/blinkInternalLED.sh>`
+
Here you see a simple bash script that turns an LED
on and off. Enter Ctrl+c to stop the script.
+Congratulations, you've blinked an LED.
+
+Your turn
+^^^^^^^^^
+
+Now that you have an LED blinking, try blinking a different LED.
+Or, blink more than one LED at a time. Try slowing down, or speeding up
+the blink rate.
+
Blinking via Python
-====================
+-------------------
Here's a script that sequences the LEDs on and off.
@@ -273,19 +292,35 @@ Here's a script that sequences the LEDs on and off.
while True:
for i in range(LEDs):
f[i].seek(0)
- f[i].write("1")
+ f[i].write("1") # 1 turns the LED on
time.sleep(0.25)
for i in range(LEDs):
f[i].seek(0)
- f[i].write("0")
+ f[i].write("0") # 0 turns the LED off
time.sleep(0.25)
bone:~$ ./seqLEDs.py
^c
-
+
+:download:`seqLEDs.py<code/seqLEDs.py>`
+
Again, hit Ctrl+c to stop the script.
+This python script is a bit more complicated that the previous bash
+script. Note that *LEDPATH* is the same in both scripts. They use the
+same interface to control the built-in LEDs. The python script opens a
+file for each of the LEDs and then writes a **1** to the file to turn on
+the LED. A **0** is writen to turn it off. The *for* loop allows it to turn
+on (or off) all four LEDs in sequence.
+
+Your turn
+^^^^^^^^^
+
+Try speeding up, or slowing down the sequencing by changing the *sleep* times.
+If you have programming experience, make a single LED sequence back and forth.
+
+
Blinking from Command Line
-==========================
+--------------------------
You can control the LEDs from the command line.
@@ -308,18 +343,18 @@ You can blink any of them. Let's try ``usr1``.
bone:~$ echo 1 > brightness
bone:~$ echo 0 > brightness
-When you echo 1 into ``brightness`` the LED turns on.
-Echoing a 0 turns it off.
+When you echo **1** into ``brightness`` the LED turns on.
+Echoing a **0** turns it off.
Blinking other LEDs
-===================
+-------------------
You can blink the other LEDs by changing in to thier
directories and doing the same. Let's blink the USR0 LED.
.. code-block:: shell-session
- bone:~$ cd ../beaglebone\:green\:usr0/
+ bone:~$ cd /sys/class/leds/beaglebone\:green\:usr0/
bone:~$ echo 1 > brightness
bone:~$ echo 0 > brightness
@@ -343,13 +378,20 @@ what triggers you can set:
bone:~$ echo none > trigger
Notice ``[heartbeat]`` is in brackets. This shows it's the
-current trigger. The echo changes the trigger to ``none``.
+current trigger. The ``echo`` changes the trigger to ``none``.
+Your turn
+^^^^^^^^^
Try experimenting with some of the other triggers and see if you
-can figure them out.
+can figure them out. Try changing the trigger on the other LEDs.
+
+.. note::
+
+ The following may not work on all Beagles since it depends on which
+ version of Debian you are running.
Another way to Blink an LED
-===========================
+---------------------------
An interesting thing about Linux is there are often many ways
to do the same thing. For example, I can think of at least five ways to blink
@@ -384,21 +426,26 @@ the ``gpioset`` command.
The first command sets chip 1, line 22 (the usr1 LED) to 1 (on) for
2 seconds. The second command turns it off for 2 seconds.
-Try it for the other LEDs.
+Your turn
+^^^^^^^^^
+
+Try turning on and off the other LEDs. If you have programming experience,
+try modifying the earler *bash* script to use `gpiod` instead of `echo`.
.. note::
- This may not work on all Beagles since it depends on which
+ The following may not work on all Beagles since it depends on which
version of Debian you are running.
-Blinking in response to a button
-=================================
+Blinking in response to a button event
+--------------------------------------
-Some Beagles have a USR button that can be used to control the LEDs.
-You can test the USR button with ``evtest``
+Some Beagles have a **USR** button that can be used to control the LEDs.
+You can test the **USR** button with ``evtest``
.. code-block:: shell-session
+ bone:~$ sudo apt install evtest
bone:~$ evtest
No device specified, trying to scan all of /dev/input/event*
Not running as root, no devices may be available.
@@ -410,7 +457,7 @@ You can test the USR button with ``evtest``
We want to use ``gpio-keys``, so enter ``1``. Press and release
the USR button and you'll see:
-.. code-block:: shell-session
+ .. code-block:: shell-session
Input driver version is 1.0.1
Input device ID: bus 0x19 vendor 0x1 product 0x1 version 0x100
@@ -439,23 +486,41 @@ the USR button and you'll see:
Event: time 1692994988.641754, -------------- SYN_REPORT ------------
Ctrl+c
-The following script uses evtest to wait for the USR button to be pressed and
-then turns on the LED.
+The value **1** means the **USR** button was pressed, the **0** means it
+was released. The value **2** means the button is being held.
-.. literalinclude:: buttonEvent.sh
- :language: Shell
+The following script uses ``evtest`` to wait for the **USR** button to be
+pressed and then turns on the LED.
+
+.. literalinclude:: code/buttonEvent.sh
:caption: buttonEvent.sh
:linenos:
-:download:`buttonEvent.sh<buttonEvent.sh>`
+:download:`buttonEvent.sh<code/buttonEvent.sh>`
+
+Try running it and pressing the **USR** button.
+
+.. code-block:: shell-session
+
+ bone:~$ ./buttonEvent.sh
+ ^c
+
+The **USR3** LED should turn on when the **USR** button is pressed.
+
+Your turn
+^^^^^^^^^
+Try modifying the code to turn on a different LED. Try blinking 2 or 3
+LEDs when the button is pressed. Can you toggle an LED each time the
+button is pressed?
-Try running it and pressing the USR button.
+Blinking in response to a button poll
+-------------------------------------
-The next script polls the USR button and toggles the LED.
+The next script polls the USR button and toggles the LED rather that waiting
+for an event.
-.. literalinclude:: buttonLED.sh
- :language: shell
+.. literalinclude:: code/buttonLED.sh
:caption: buttonLED.sh
:linenos:
-:download:`buttonLED.sh<buttonLED.sh>`
+:download:`buttonLED.sh<code/buttonLED.sh>`
diff --git a/intro/beagle101/code/blinkInternalLED.sh b/intro/beagle101/code/blinkInternalLED.sh
new file mode 100755
index 00000000..485c563d
--- /dev/null
+++ b/intro/beagle101/code/blinkInternalLED.sh
@@ -0,0 +1,10 @@
+LED="3"
+
+LEDPATH='/sys/class/leds/beaglebone:green:usr'
+
+while true ; do
+ echo "1" > ${LEDPATH}${LED}/brightness
+ sleep 0.5
+ echo "0" > ${LEDPATH}${LED}/brightness
+ sleep 0.5
+done
diff --git a/intro/beagle101/buttonEvent.sh b/intro/beagle101/code/buttonEvent.sh
similarity index 100%
rename from intro/beagle101/buttonEvent.sh
rename to intro/beagle101/code/buttonEvent.sh
diff --git a/intro/beagle101/buttonLED.sh b/intro/beagle101/code/buttonLED.sh
similarity index 100%
rename from intro/beagle101/buttonLED.sh
rename to intro/beagle101/code/buttonLED.sh
diff --git a/intro/beagle101/code/seqLEDs.py b/intro/beagle101/code/seqLEDs.py
new file mode 100755
index 00000000..40f684a9
--- /dev/null
+++ b/intro/beagle101/code/seqLEDs.py
@@ -0,0 +1,21 @@
+import time
+import os
+
+LEDs=4
+LEDPATH='/sys/class/leds/beaglebone:green:usr'
+
+Open a file for each LED
+f = []
+for i in range(LEDs):
+ f.append(open(LEDPATH+str(i)+"/brightness", "w"))
+
+Sequence
+while True:
+ for i in range(LEDs):
+ f[i].seek(0)
+ f[i].write("1") # 1 turns the LED on
+ time.sleep(0.25)
+ for i in range(LEDs):
+ f[i].seek(0)
+ f[i].write("0") # 0 turns the LED off
+ time.sleep(0.25)
--
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