Pi install - Teh Forum

<body> <div id="header"> <span class="left"> <span class="back"><a href="lthread_list.php?webtag=DEFAULT"><span class="image mobile_back" title="Back"></span></a></span> <span class="image mobile_logo" title="Beehive Forum Logo"></span> </span> <ul> <li> <a class="reply_all" href="lpost.php?webtag=DEFAULT&reply_to=42216.0&return_msg=42216.8"> <span class="image mobile_reply_all"></span><span class="text">Reply to All</span> </a> </li> <li> <a class="navigation" href="#"> <span class="image mobile_navigation"></span><span class="text">Show messages</span> </a> </li> <li> <a class="main" href="#"><span class="image mobile_menu" title="Menu"></span> </a> </li> </ul> </div> <div class="menu main"> <ul> <li><a href="lthread_list.php?webtag=DEFAULT">Messages</a></li> <li><a href="lpm.php?webtag=DEFAULT">Inbox</a></li> <li><a href="lsearch.php?webtag=DEFAULT">Search</a></li> <li><a href="llogon.php?webtag=DEFAULT">Login</a></li> </ul> </div> <div class="menu navigation"><a href="lmessages.php?webtag=DEFAULT&msg=42216.1">1–10</a><a href="lmessages.php?webtag=DEFAULT&msg=42216.11">11–20</a>…<a href="lmessages.php?webtag=DEFAULT&msg=42216.91">91–92</a></div> <div id="page_content"> <h3 class="thread_title"><a href="index.php?webtag=DEFAULT&amp;msg=42216.8">Pi install</a> </h3> <div id="messages" data-navigation="42216_8_92_10"> <a name="a42216_8"></a><div class="message" id="message_42216_8"> <div class="message_header"> <div class="message_from"> From: Peter (BOUGHTONP)<span class="message_time">19 Aug 2018 21:56</span> <div class="clearer"></div> </div><div class="message_to">To: graphitone <span><span class="image post_read" title="Read: 19 Aug 2018 21:57"></span></span> <span class="message_count">8 of 92</span><div class="clearer"></div> </div> </div> <div class="message_links"> <a href="lmessages.php?webtag=DEFAULT&msg=42216.8">42216.8</a> In reply to <a href="lmessages.php?webtag=DEFAULT&msg=42216.7">42216.7</a></div> <div class="message_body"> Your final two commands are regular shell (e.g. Bash) whereas your main script is Python (as per the #! line at the start). <p>What "echo A > B" is does is write content A to file B - the closest equivalent in Python seems to be print: </p><pre> print('0',file='/sys/class/backlight/rpi_backlight/bl_power')</pre> <p>But the recommended way appears to be this convoluted thing: </p><pre> with open('/sys/class/backlight/rpi_backlight/bl_power','w') as f: f.write('0')</pre> <p>Possibly using <var>buttonState1</var> instead of 0 and 1 ...and actually looking at the code, I just noticed you've got subprocess.call calling what looks like a shutdown shell command, so you can simply use that for shell commands without needing to translate - possibly changing the shutdown one to: </p><pre>"echo 1 > /sys/class/backlight/rpi_backlight/bl_power && shutdown -h now"</pre> and adding the inverse for starting up - it seems weird to have this in an endless polling loop (the while true + sleep combo), but maybe that's the only way this stuff works? <span class="emoticon e_unsure" title=":/"><span class="e__">:/</span></span></div> <div class="message_footer"> <div class="message_footer_links"><a href="lpost.php?webtag=DEFAULT&reply_to=42216.8&return_msg=42216.8" class="reply"><span class="image post"></span>Reply</a></div> <div class="message_vote_form" data-msg="42216.8"> <span class="rating">0/0</span> <span class="image vote vote_down vote_down_off" title="Vote Down"></span> <span class="image vote vote_up vote_up_off" title="Vote Up"></span> </div> </div> </div><a name="a42216_9"></a><div class="message" id="message_42216_9"> <div class="message_header"> <div class="message_from"> From: Peter (BOUGHTONP)<span class="message_time">19 Aug 2018 22:29</span> <div class="clearer"></div> </div><div class="message_to">To: graphitone <span><span class="image post_read" title="Read: 20 Aug 2018 06:01"></span></span> <span class="message_count">9 of 92</span><div class="clearer"></div> </div> </div> <div class="message_links"> <a href="lmessages.php?webtag=DEFAULT&msg=42216.9">42216.9</a> In reply to <a href="lmessages.php?webtag=DEFAULT&msg=42216.7">42216.7</a></div> <div class="message_body"> So I checked and you don't need to (and shouldn't) do the polling method - i.e. constantly checking the status every 0.1 seconds - you can instead simply listens for when changes occur. <p>See Threaded callbacks in this page: <a href="https://sourceforge.net/p/raspberry-gpio-python/wiki/Inputs/">https://sourceforge.net/p/raspberry-gpio-python/wiki/Inputs/</a> </p><p>Basically you might be able to swap the while loop for something like this: </p><pre>def onButtonPress(channel): if GPIO.input(channel) shell_command = "echo 0 > /sys/class/backlight/rpi_backlight/bl_power && shutdown -h now"; else shell_command = "echo 1 > /sys/class/backlight/rpi_backlight/bl_power"; subprocess.call(shell_command, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE) GPIO.add_event_detect(5, GPIO.BOTH, callback=onButtonPress)</pre> <p>That still isn't the greatest code, but it's (possibly) good enough, assuming it works; I don't know Python or understand what I've read of the GPIO stuff, so... *shrug* <span class="emoticon e_smile" title=":)"><span class="e__">:)</span></span></p></div> <div class="message_footer"> <div class="message_footer_links"><a href="lpost.php?webtag=DEFAULT&reply_to=42216.9&return_msg=42216.8" class="reply"><span class="image post"></span>Reply</a></div> <div class="message_vote_form" data-msg="42216.9"> <span class="rating">0/0</span> <span class="image vote vote_down vote_down_off" title="Vote Down"></span> <span class="image vote vote_up vote_up_off" title="Vote Up"></span> </div> </div> </div><a name="a42216_10"></a><div class="message" id="message_42216_10"> <div class="message_header"> <div class="message_from"> From: ANT_THOMAS<span class="message_time">20 Aug 2018 11:46</span> <div class="clearer"></div> </div><div class="message_to">To: graphitone <span><span class="image post_read" title="Read: 20 Aug 2018 14:17"></span></span> <span class="message_count">10 of 92</span><div class="clearer"></div> </div> </div> <div class="message_links"> <a href="lmessages.php?webtag=DEFAULT&msg=42216.10">42216.10</a> In reply to <a href="lmessages.php?webtag=DEFAULT&msg=42216.7">42216.7</a></div> <div class="message_body"> Definitely interested to see how it all turns out.<br /> I've played with Pis for audio stuff and bought a few DACs and even started making a breakout board for some switches, IR etc.<br /> But had a few too many issues with volumio (I was going headless). <br /> <br /> Eventually scraped the idea and went to Chromecast Audios where I want streamed audio. <br /> Stuck them in the bathroom, kitchen, living room, bedroom. <br /> <br /> Main use is in the kitchen and occasionally bathroom. </div> <div class="message_footer"> <div class="message_footer_links"><a href="lpost.php?webtag=DEFAULT&reply_to=42216.10&return_msg=42216.8" class="reply"><span class="image post"></span>Reply</a></div> <div class="message_vote_form" data-msg="42216.10"> <span class="rating">0/0</span> <span class="image vote vote_down vote_down_off" title="Vote Down"></span> <span class="image vote vote_up vote_up_off" title="Vote Up"></span> </div> </div> </div><a name="a42216_11"></a><div class="message" id="message_42216_11"> <div class="message_header"> <div class="message_from"> From: graphitone<span class="message_time">20 Aug 2018 14:29</span> <div class="clearer"></div> </div><div class="message_to">To: ANT_THOMAS <span><span class="image post_read" title="Read: 20 Aug 2018 15:01"></span></span> <span class="message_count">11 of 92</span><div class="clearer"></div> </div> </div> <div class="message_links"> <a href="lmessages.php?webtag=DEFAULT&msg=42216.11">42216.11</a> In reply to <a href="lmessages.php?webtag=DEFAULT&msg=42216.8#a42216_10" target="_self">42216.10</a></div> <div class="message_body"> I'll keep the thread updated.<br /><br /> I'll have a go with PB suggestions tonight for the backlight on the screen.<br /><br /> I'm trying to make it as easy to use as possible, so the rest of the family only have to press a power button and then they've got control over the whole thing. To that end, I'll need a volume control as well, so I've been reading <a href="https://volumio.org/forum/gpio-pins-control-volume-t2219.html">this </a>about putting a potentiometer in as a volume knob. It's written for Volumio, but providing I can get the stuff they suggest into Libreelec it should be ok.<br /><br /> In my mind the screen'll be mounted flush (or as flush as can be) in the wall, all wiring hidden away but the power taken to a switched mains socket in a cupboard underneath the worktop. I'll have to find a way to make it easily removable, for upgrades and what not.</div> <div class="message_footer"> <div class="message_footer_links"><a href="lpost.php?webtag=DEFAULT&reply_to=42216.11&return_msg=42216.8" class="reply"><span class="image post"></span>Reply</a></div> <div class="message_vote_form" data-msg="42216.11"> <span class="rating">0/0</span> <span class="image vote vote_down vote_down_off" title="Vote Down"></span> <span class="image vote vote_up vote_up_off" title="Vote Up"></span> </div> </div> </div><a name="a42216_12"></a><div class="message" id="message_42216_12"> <div class="message_header"> <div class="message_from"> From: graphitone<span class="message_time">22 Aug 2018 06:45</span> <div class="clearer"></div> </div><div class="message_to">To: ALL<span class="message_count">12 of 92</span><div class="clearer"></div> </div> </div> <div class="message_links"> <a href="lmessages.php?webtag=DEFAULT&msg=42216.12">42216.12</a></div> <div class="message_body"> I did a wrong. <span class="emoticon e_csad" title=":C"><span class="e__">:C</span></span><br /><br /> Somehow I've lost all sound. Instead of arseing about trying to put the config right, I'm going to wipe the SD card and start again and put what I know works in, make a backup (!) and then troubleshoot it.</div> <div class="message_footer"> <div class="message_footer_links"><a href="lpost.php?webtag=DEFAULT&reply_to=42216.12&return_msg=42216.8" class="reply"><span class="image post"></span>Reply</a></div> <div class="message_vote_form" data-msg="42216.12"> <span class="rating">0/0</span> <span class="image vote vote_down vote_down_off" title="Vote Down"></span> <span class="image vote vote_up vote_up_off" title="Vote Up"></span> </div> </div> </div><a name="a42216_13"></a><div class="message" id="message_42216_13"> <div class="message_header"> <div class="message_from"> From: ANT_THOMAS<span class="message_time">22 Aug 2018 07:39</span> <div class="clearer"></div> </div><div class="message_to">To: graphitone <span><span class="image post_read" title="Read: 22 Aug 2018 12:20"></span></span> <span class="message_count">13 of 92</span><div class="clearer"></div> </div> </div> <div class="message_links"> <a href="lmessages.php?webtag=DEFAULT&msg=42216.13">42216.13</a> In reply to <a href="lmessages.php?webtag=DEFAULT&msg=42216.8#a42216_12" target="_self">42216.12</a></div> <div class="message_body"> Do you know how to make a backup image of an SD?<br /> <br /> Very useful to have at least a basic configured image to go back to if you do a wrong. </div> <div class="message_footer"> <div class="message_footer_links"><a href="lpost.php?webtag=DEFAULT&reply_to=42216.13&return_msg=42216.8" class="reply"><span class="image post"></span>Reply</a></div> <div class="message_vote_form" data-msg="42216.13"> <span class="rating">0/0</span> <span class="image vote vote_down vote_down_off" title="Vote Down"></span> <span class="image vote vote_up vote_up_off" title="Vote Up"></span> </div> </div> </div><a name="a42216_14"></a><div class="message" id="message_42216_14"> <div class="message_header"> <div class="message_from"> From: CHYRON (DSMITHHFX)<span class="message_time">22 Aug 2018 12:18</span> <div class="clearer"></div> </div><div class="message_to">To: ANT_THOMAS <span><span class="image post_read" title="Read: 22 Aug 2018 13:02"></span></span> <span class="message_count">14 of 92</span><div class="clearer"></div> </div> </div> <div class="message_links"> <a href="lmessages.php?webtag=DEFAULT&msg=42216.14">42216.14</a> In reply to <a href="lmessages.php?webtag=DEFAULT&msg=42216.8#a42216_13" target="_self">42216.13</a></div> <div class="message_body"> I did exactly that to quickly recover from a botched xfce install using fsarchiver. Dunno if that works on an sd card, I've never backed one up.</div> <div class="message_footer"> <div class="message_footer_links"><a href="lpost.php?webtag=DEFAULT&reply_to=42216.14&return_msg=42216.8" class="reply"><span class="image post"></span>Reply</a></div> <div class="message_vote_form" data-msg="42216.14"> <span class="rating">0/0</span> <span class="image vote vote_down vote_down_off" title="Vote Down"></span> <span class="image vote vote_up vote_up_off" title="Vote Up"></span> </div> </div> </div><a name="a42216_15"></a><div class="message" id="message_42216_15"> <div class="message_header"> <div class="message_from"> From: graphitone<span class="message_time">22 Aug 2018 12:21</span> <div class="clearer"></div> </div><div class="message_to">To: ANT_THOMAS <span><span class="image post_read" title="Read: 22 Aug 2018 13:02"></span></span> <span class="message_count">15 of 92</span><div class="clearer"></div> </div> </div> <div class="message_links"> <a href="lmessages.php?webtag=DEFAULT&msg=42216.15">42216.15</a> In reply to <a href="lmessages.php?webtag=DEFAULT&msg=42216.8#a42216_13" target="_self">42216.13</a></div> <div class="message_body"> Aye, I'm gonna get a base setup and make an image - don't really know why I didn't do it the first time round. <span class="emoticon e_csad" title=":C"><span class="e__">:C</span></span></div> <div class="message_footer"> <div class="message_footer_links"><a href="lpost.php?webtag=DEFAULT&reply_to=42216.15&return_msg=42216.8" class="reply"><span class="image post"></span>Reply</a></div> <div class="message_vote_form" data-msg="42216.15"> <span class="rating">0/0</span> <span class="image vote vote_down vote_down_off" title="Vote Down"></span> <span class="image vote vote_up vote_up_off" title="Vote Up"></span> </div> </div> </div><a name="a42216_16"></a><div class="message" id="message_42216_16"> <div class="message_header"> <div class="message_from"> From: ANT_THOMAS<span class="message_time">22 Aug 2018 13:07</span> <div class="clearer"></div> </div><div class="message_to">To: CHYRON (DSMITHHFX) <span><span class="image post_read" title="Read: 22 Aug 2018 13:28"></span></span> <span class="message_count">16 of 92</span><div class="clearer"></div> </div> </div> <div class="message_links"> <a href="lmessages.php?webtag=DEFAULT&msg=42216.16">42216.16</a> In reply to <a href="lmessages.php?webtag=DEFAULT&msg=42216.8#a42216_14" target="_self">42216.14</a></div> <div class="message_body"> The method I use is a bit crude but works surprisingly well.<br /> I use "dd" to clone the SD card location (something like /dev/mmblock0) to a network location.<br /> <br /> Works on a running system which is nice. You can even run the command through gzip to compress the free space and shrink the storage required for the image. Slows the process down though. Requires a same or larger size SD to restore. </div> <div class="message_footer"> <div class="message_footer_links"><a href="lpost.php?webtag=DEFAULT&reply_to=42216.16&return_msg=42216.8" class="reply"><span class="image post"></span>Reply</a></div> <div class="message_vote_form" data-msg="42216.16"> <span class="rating">0/0</span> <span class="image vote vote_down vote_down_off" title="Vote Down"></span> <span class="image vote vote_up vote_up_off" title="Vote Up"></span> </div> </div> </div><a name="a42216_17"></a><div class="message" id="message_42216_17"> <div class="message_header"> <div class="message_from"> From: CHYRON (DSMITHHFX)<span class="message_time">22 Aug 2018 13:28</span> <div class="clearer"></div> </div><div class="message_to">To: ANT_THOMAS <span><span class="image post_read" title="Read: 22 Aug 2018 13:35"></span></span> <span class="message_count">17 of 92</span><div class="clearer"></div> </div> </div> <div class="message_links"> <a href="lmessages.php?webtag=DEFAULT&msg=42216.17">42216.17</a> In reply to <a href="lmessages.php?webtag=DEFAULT&msg=42216.8#a42216_16" target="_self">42216.16</a></div> <div class="message_body"> Ah. I was going to suggest the "dd" method but didn't know if it worked on sd cards.</div> <div class="message_footer"> <div class="message_footer_links"><a href="lpost.php?webtag=DEFAULT&reply_to=42216.17&return_msg=42216.8" class="reply"><span class="image post"></span>Reply</a></div> <div class="message_vote_form" data-msg="42216.17"> <span class="rating">0/0</span> <span class="image vote vote_down vote_down_off" title="Vote Down"></span> <span class="image vote vote_up vote_up_off" title="Vote Up"></span> </div> </div> </div></div> <div class="message_page_footer"> <ul> <li class="right_col"><form accept-charset="utf-8" method="get" action="lmessages.php" target="_self"><input type="hidden" name="webtag" id="webtag" class="bhinputtext" value="DEFAULT" dir="ltr" /><input type="hidden" name="msg" id="msg" class="bhinputtext" value="42216.18" dir="ltr" /><input type="submit" name="submit" id="keep_reading" value="Keep reading…" class="button" /></form></li> </ul> </div> </div> </body>