I belong to a small hobby organization, and assist with simple techy things that can help the group in various ways, like helping maintain the website.
A while back, the group was looking for a simpler way to be sure that they could communicate effectively and easily among the groups executive, using email. This sounds easy, but in a group of 10, someone always seems to get left out of group emails sent from personal email accounts, or the wrong email gets included in a list, or emails get left in someone's personal list, that are no longer needed.
The group experimented with setting up a shared gmail account for this purpose, but gmail account security makes it very hard to share a single account, accessed from multiple locations. Next up was a google discussion group, but that had it's own list of complexities.
So I suggested we just set up an Old School email list service. You know, the ones were you define an email account, give a list of other emails to forward to, and just send anythng you want to share to it, for automatic forwarding to everyone. The list gets maintained in one place, and we are done.
Well, they still exist, but most are commercial Marketing remailers, with tons of bells and whistles, and probably lots of other strings attached. Some are free for entry level use, but I didn't spend too much time on them after looking into FreeLists.org .
FreeLists.org has been around for quite a while. They are truly free, although they do not accept just anyone. However our group met their criteria, so we set up our first list, and populated it with some emails and started testing. Everything went fairly well, and we were happy, until one of our members sent out a test, and we discovered that his Reply To: email had been Redacted, and replaced with "dmarc-noreply@freelists.org" . An interesting problem! Since I already had one request for advice in the hands of the FreeLists Staff, I decided to nibble at this one for a while myself.
DMARC and Spam:
In my research, I learned there is an anti-spam toolset used by
major email providers world-wide, known as DMARC. One of the things
DMARC does is allow email providers to identify the domain names they
use to send email from (like gmail.com, cogeco.com, rogers.com, etc),
and to embed that knowledge in several secure ways in emails and in
Domain Name Servers (the "address book" of the internet), to allow
receiving email services to securely determine if a given email has
actually come from the email service it says it originated from (the
"domain name" test).
Reject or Ignore:
Email sending services can also optionally tell a receiving email
service what to do with email that fails this "domain name" test: either
reject the email, or ignore it (allowing the receiving email service to
decide what to do about it instead). When DMARC was first rolled out in
2012 - 2013, this failure action was defaulted to ignore, by virtually
everyone who implemented DMARC.
Yahoo got Spammed:
In early April, 2014, Yahoo.com was hit by major email spammers, who
were spoofing the yahoo.com domain name, and creating havoc among
yahoo email users and others. Yahoo made a quick decision one weekend
to change the DMARC failure action for their domain name from ignore to
reject. In doing so, all mail list and other remailing applications
that included any yahoo email users, broke instantly (their email
spoofing problem was solved, though). Not only did they fail, but the
resulting error messages began bouncing back, and some of the bounces
resulted in further rejects and bounces... See
https://www.pcworld.com/article/2141120/yahoo-email-antispoofing-policy-breaks-mailing-lists.html
for further information.
Fixing Mail Lists:
Mail List and other remailing service providers needed to deal with
this, including our Mail List provider Freelists.org. DMARC also
provided some work-arounds. See for example
https://www.spamresource.com/2014/04/run-email-discussion-list-heres-how-to.html
. At the time, FreeLists.org Facebook page reported:
" Freelists - Freelists.org April 19, 2014 ·
A solution to DMARC-related issues has been developed and is being
tested on a handful of lists that reported deliverability problems to
us. Should feedback be positive, we'll continue rolling this out to the
entire site in the coming days.
Let us (staff@freelists.org) know if you'd like advance access to
the fix, which replaces the subscriber's From: address with an "address
redacted" sort of message when posting IF his mail provider publishes
DMARC records."
Another common fix was to ask Yahoo email users to switch to another
major email provider, like Gmail or Outlook...
So why did our Rogers.com Member get Redacted?
Examining the email header of messages from our Rogers User showed references to Yahoo! Now that is very interesting! No other user of our list had such references in their email headers. But further research quickly uncovered the fact that Rogers has outsourced it's email to Yahoo.ca!!
I then discovered the toolset at the website dmarcian.com: https://dmarcian.com/dmarc-inspector/yahoo.ca
I ran this for the Rogers.Yahoo.ca email service, and determined that "p=reject", which is why our member's email is getting redacted. His email provider prevents him from full use of a mail list.
In conclusion, our member gets to decide if a redacted reply address is okay when he uses our list, or if he will set up a different email account, to gain full use of the list.
We can also move forward to add a list that allows us to email amongst our total membership efficiently.
Saturday, 3 February 2018
Saturday, 20 January 2018
My NAS Experiences...
About a year ago, I embarked on the learning curve needed to implement a NAS (Network Accessable Storage) Server on my home Network. A good opportunity to put one more of those old cast-off PCs to work, and find a home for those digital photos accumulating in various places.
System 1: NAS4Free and PIII
After reading up on the several freeware type NAS implementations available, I decided an old PIII system with 500MB RAM would be good enough. The box was small, did not use as much power as some of the other boxes I had sitting in the corner. I stuck an old Maxtor 40GB PATA hard drive in it for the OS and NAS software, scrounged around until I found a PCI bus SATA card to use, and installed a 1TB SATA drive for Data. INstalled Ubuntu Server OSA, which I had some experience with, then installed my first choice, NAS4Free. Although I got it installed okay, I seemed to have a lot of trouble setting up appropriate security to be able to see it from other Windows and Linux boxes on my Network. Maybe it was me; others have used it successfully, but I was having lots of frustration...
Version 2: Switch to OpenMediaVault (OMV), & Pictures!
So I started over, with OMV V2.1 OMV's install ISO does a very nice job of installing Debian and OMV on the Maxtor drive, and finding and setting up the Data drive on the 1TB SATA drive I had installed. I was able to easily setup a number of data shares, and several classes of users, and see everything easily across my network. The web admin panel works very well.
I started to load pictures, from my Win10 PC, and had some more learning to do. Fortunately others have been there before, and I can refer you to Awasu Consulting's very good articles on Open Media Vault, esp. the one entitled "Configuring Open Media Vault", and the section "Uploading Files to the NAS".
- https://awasu.com/weblog/omv-bpi/configuring-omv/
Other backgrounders I found helpful include:
- https://www.howtogeek.com/176471/how-to-share-files-between-windows-and-linux/
- https://www.howtogeek.com/howto/16196/how-to-disconnect-non-mapped-unc-path-drives-in-windows/
Soon I had uploaded many thousands of pics and videos from several vacations of the past several years, and made them available across our home network, and accessible from several different kinds of devices. I have found Kodi to be an excellent Media Server, running on inexpensive Android based OTT boxes (about $30 each), feeding from the NAS box, and connected to TVs and a stereo in several rooms of the house. Kodi is also easily controlled either locally on the TV, with the included IR remote control, or over WiFi, from our Android or iOS phones and tablets. A very nice arrangement!
More Data: Movies and Music
Of course, there is lots more to do after these initial successes! I added another 0.7TB SATA drive I had on hand, configured and shared it, and started to add Movies from our in-house collection, accumulated over a number of years. Soon there were 200 Movies online and easily accessible, complete with supporting information courtesy of the Kodi installed movie information scraper apps.
And all those music CDs! Some had already been ripped, but we had lots more to do... Soon there were 1000 or so music CDs online, although since some had been ripped by different people, using different tools and formats, there was a lot of cleanup of existing digital files, so all the music was presented in a common way... The Windows Media tools, and others, help a lot in setting this up, and Kodi is very happy using the repository so produced.
Setback 1: SATA Card Failure & System 2
And then the plug in PCI bus SATA card I was using failed.... I didn't have another, but I did have lots of other PCs in the corner. This time I picked a slightly newer, more powerful Acer box, with all the right interfaces, 1GB of RAM, and an AMD Athlon 64b cpu, running at 2.7GHz. A bit more power hungry, but we were happy with the results of having a NAS server online. The hard drives installed easily, and the system booted up. Back in business! (I ordered another PCI SATA card, just to have around for future use).
Setback 2: Power Supply Failure, and System 3
A week ago, the power went out in our neighbourhood for a few hours. A rare occurrence, but no big deal, except the NAS server did not restart. Upon investigation, discovered that it's power supply, a Liteon branded 250W ATX12V supply, had failed. Some research showed that this was a not uncommon problem in Acer PCs with this supply, once you add additional SATA drives to them!!
A search through my collection of surplus PCs showed a few had ATX12V supplies, but not with the same motherboard connections (20pin vs 24pin power connectors). There was also the question of just how much power the mb needed, and if the extra 4 pins were needed. Unfortunately, Acer refuses to make any tech information on their motherboards public, so there is no way to answer these questions! A new replacement supply was going to be about $40, but I did have a surplus PC, with the appropriate hard drive interfaces, and a better power supply reputation (an IBM / Lenovo PC). It also had an even faster cpu, and 1.5GB of RAM.
So I moved the hard drive collection over, leaving the existing CD-ROM drive in place on the IDE0 cable, adding the Maxtor 40GB OS/NAS drive to the same cable, and plugging the 2 SATA Data drives to the 2 available SATA connectors, after removing the SATA hard drive that was originally in this machine. I was expecting an easy reboot, and back in business. Not so easy....
GRUB RESCUE>
Well, I had never run into this problem before. It was accompanied with the error: "hd0 read error"
The BIOS sees the hard drives okay, although it is enumerating them in a different order than the previous PC did. Did this matter? No idea...
The system boots ok from the Super Grub Rescue CD Recovery disk, and sees the hard drives okay. I try several Grub recovery methods, but no luck. But sometimes the CD doesn't boot... and I realize the BIOS doesn't see the CD drive...
After more googling, I finally realize I should check the jumper settings on the PATA devices, since they are both on the same cable... Yup, two Masters. (Shows how long it has been since I had to configure IDE drives!)
After fixing that problem, I have reliable CD booting, but still no success with Grub repairs.
On to a more general purpose System Rescue Bootable CD, and it's also time to disconnect the SATA drives, just in case...
Gparted is happy with the partitions it is finding on the 40GB drive, as described in the OMV information. However, other tools are not happy with the ext4 file system, complaining of a invalid superblock.
I switched to using Testdisk, after finding several good references online describing how to use it effectively (it is a complex tool). By this time, I am in uncharted territory wrt my knowledge of Linux and it's file system details, so this is both fascinating and frustrating territory. I am learning a lot. I am using my "Practical Guide to Ubuntu Linux" (4th Edition, by Mark Sobell) a lot, too.
I was able to obtain the list of backup superblocks on the disk, tried fsck repairs with most of them, but no success.
Reinstall OMV, V3.0.94
I was wary of a re-install, since I did not want to have to rebuild the contents of the data disks, if they had to be re-initialized. However, after more research, it looked like OMV could mount and share existing populated data disks, and that turned out to be the case. I downloaded the latest stable release of OMV, rebuilt the 40GB OS disk with no problems, added the 2 data disks to the system, and began reconfiguring the system on my network. Although my previous NAS configuration notes were not quite complete, I had no difficulty mounting and sharing the drives and their data folders, adding the users I had previously setup, configuring services and access rights, and getting everything back to normal. And my configuration notes are in great shape now!!
So overall a success, although it took several days to work through the details.
Next time, I will go to a full rebuild of the OS drive much quicker...
Thursday, 23 November 2017
New Life for Old Tablets
As a techie, I have collected a number of tablets over the years. There's a couple of very senior Pandigital Novels (Android 1.5), a middle-aged Kobo monochrome e-reader with wi-fi (non-functional due to an auto update from Kobo that was buggy, but apparently recoverable, when I have time...), a 7 inch Chinese tablet ("Diverseway MID7007" )running Android V4.2.2, and my main tablet, a 2012-era Samsung Galaxy Tab 10.1 . (not counting the cast off older smartphones I have accumulated, a few of which run early Android versions, and some early iPhones...)
Google Crashes Tablets...
However, earlier this year, the Galaxy started to show frequent crash error messages from various Google Play apps, and the Google Browser would crash often on websites with complex page components (CBC.CA was a big problem, but far from the only one). The Firefox Browser also had a lot of trouble with complex pages. This was making the tablet unpleasant to use for news feeds, and other uses.
So began my search for a fix. The tablet has reasonable hardware (ArmV7 dual core 32b cpu, 1Ghz, 722MB reported RAM (likely an actual 1GB..?) , 32GB internal storage), good display, wifi, bluetooth, various sensors, GPS and excellent battery life. The OS was at Android V4.0.4 (ICS), Samsung's last official update for this tablet model.
Emphasis on Due Diligence Research...
Some online reading identified:
1- a lot of activity noted on multiple websites, regarding Android updates for this model. Much discussion around updates from V3 and V4.0 to: V4.1, 4.2, 4.4, 5.0, 5.1, and even a bit of work on V6 and V7! Multiple sources / groups identified as involved, but most common references are to: the Android Open Source Project (AOSP), a fork called AOKP, and the CyanogenMod CM series of Android updates. The CyanogenMod CM series became LineAge OS series last year. The LineAge OS series officially doesn't list any updates going back more than a few years.
2- The likely cause of Google Apps failures (google's upgrades to NEON instruction set, with no support for older cpu sets), and some likely strategies to overcome this (rollback to earlier Google apps versions, ways to prevent auto-updates, and apparently kernel? updates to simulate the NEON instruction set components otherwise missing.)
3- safe and effective procedures to perform the OS update, using tools like TWRP, CWM, Odin3...
The Direction Forward...
So the direction forward seemed clear. I elected to update to an Unofficial AOSP-based Android 5.1.1 Lollipop, using TWRP and Odin3. There is a huge amount of discussion available about this update, esp. on the xda-developers website. This work was done / led by senior developer "decatf", for whom I have incredible respect, given not only the excellence of his work, but his extensive involvement and support of those who asked for help along the way to using his work. Many thanks!
The First Success...
Although I have extensive background in small computing hardware and software, this class of update flashing for Android devices was new to me. I elected to start with one of the Pandigital Novels, since no big deal if I bricked it! There is also extensive discussion of updates for this device, including Pandigital's interesting use of variations in Models to identify regional sales areas of the same device. It's important to know what exact model you are going to update, and most of the discussion evolved around US model #s, rather than the Canadian model # on the device I have. But this soon got clarified, and I was able to identify a likely update candidate, and successfully update one of my Black PDNs from V1.5 to V2.1 !. There are a few glitches, as yet unresolved, that prevent reliable operation of the Google Browser, but the likely cause is too little space in the OS partitions. It's a known problem, with some documented fixes, so when there is time, I may look into this further, but not a priority now. Otherwise, a very useful update, using xda-developer "terminander" 's V2.1 update, as documented on the thread "Android 2.1 on the original BPDN --- coming to a channel near you". Again, many thanks!
Onward...
So, on to the real goal, that of updating my Galaxy Tab. Gathering the selected components was straightforward. It is important to use a correct Samsung USB Driver to communicate between Odin3 on my W10 PC, and the tablet, in it's Download mode. I had installed an old version of Samsung Kies some years ago in support of an early cell phone, and forgot about it. Installing the latest Samsung USB driver package seemed to cause some problems with Odin, but the underlying cause was never clear. After multiple uninstalls, and re-installs of a couple of versions of the Driver, and lots of Reboots, and some analysis of my USB subsytem with the marvelous USB TreeView utility (part of the MS Driver Dev Kit, and supported and improved by Uwe Sieber), I was able to see the tablet's download connection in Odin!
The Samsung standard Download / Recovery Tool is useful and deceptively simple. So simple, in fact, that no-one really bothers to clearly and correctly describe how to invoke it, and cause it to actually begin a USB download!! After some twiddling and references to the many partial notes online about how to get the actual download to begin, wondering all the time if this was a USB driver issue, things finally came together, and the TWRP Recovery Utility (twrp2870-20150814-p4wifi.zip) began to download and install, with no further issues.
Everything else was easy from this point on! Be sure to use decatf's update to the AOSP 5.1.1 ROM file, from 20171009 . It worked great for me. I also installed the Google Play program set in p75xx-gapps-L-7-17-15.zip, with no problems.
I now have an updated Galaxy Tab 10.1, running well, without the problems I had before, and with some additional capabilities, such as overclocking, I have yet to explore.
The updated Android has a different look to it, wrt V4.0.4 . It is very familiar, since it tends to match the appearance of my Nexus 5 smartphone, which runs Android V6.0.1 !
 |
| Fig 1- About Page of my Samsung Galaxy Tab 10.1, Pre Update |
Google Crashes Tablets...
However, earlier this year, the Galaxy started to show frequent crash error messages from various Google Play apps, and the Google Browser would crash often on websites with complex page components (CBC.CA was a big problem, but far from the only one). The Firefox Browser also had a lot of trouble with complex pages. This was making the tablet unpleasant to use for news feeds, and other uses.
So began my search for a fix. The tablet has reasonable hardware (ArmV7 dual core 32b cpu, 1Ghz, 722MB reported RAM (likely an actual 1GB..?) , 32GB internal storage), good display, wifi, bluetooth, various sensors, GPS and excellent battery life. The OS was at Android V4.0.4 (ICS), Samsung's last official update for this tablet model.
Emphasis on Due Diligence Research...
Some online reading identified:
1- a lot of activity noted on multiple websites, regarding Android updates for this model. Much discussion around updates from V3 and V4.0 to: V4.1, 4.2, 4.4, 5.0, 5.1, and even a bit of work on V6 and V7! Multiple sources / groups identified as involved, but most common references are to: the Android Open Source Project (AOSP), a fork called AOKP, and the CyanogenMod CM series of Android updates. The CyanogenMod CM series became LineAge OS series last year. The LineAge OS series officially doesn't list any updates going back more than a few years.
2- The likely cause of Google Apps failures (google's upgrades to NEON instruction set, with no support for older cpu sets), and some likely strategies to overcome this (rollback to earlier Google apps versions, ways to prevent auto-updates, and apparently kernel? updates to simulate the NEON instruction set components otherwise missing.)
3- safe and effective procedures to perform the OS update, using tools like TWRP, CWM, Odin3...
 |
| Fig 2- AOSP Android 5.1.1 Lollipop Update Thread |
So the direction forward seemed clear. I elected to update to an Unofficial AOSP-based Android 5.1.1 Lollipop, using TWRP and Odin3. There is a huge amount of discussion available about this update, esp. on the xda-developers website. This work was done / led by senior developer "decatf", for whom I have incredible respect, given not only the excellence of his work, but his extensive involvement and support of those who asked for help along the way to using his work. Many thanks!
The First Success...
Although I have extensive background in small computing hardware and software, this class of update flashing for Android devices was new to me. I elected to start with one of the Pandigital Novels, since no big deal if I bricked it! There is also extensive discussion of updates for this device, including Pandigital's interesting use of variations in Models to identify regional sales areas of the same device. It's important to know what exact model you are going to update, and most of the discussion evolved around US model #s, rather than the Canadian model # on the device I have. But this soon got clarified, and I was able to identify a likely update candidate, and successfully update one of my Black PDNs from V1.5 to V2.1 !. There are a few glitches, as yet unresolved, that prevent reliable operation of the Google Browser, but the likely cause is too little space in the OS partitions. It's a known problem, with some documented fixes, so when there is time, I may look into this further, but not a priority now. Otherwise, a very useful update, using xda-developer "terminander" 's V2.1 update, as documented on the thread "Android 2.1 on the original BPDN --- coming to a channel near you". Again, many thanks!
Onward...
So, on to the real goal, that of updating my Galaxy Tab. Gathering the selected components was straightforward. It is important to use a correct Samsung USB Driver to communicate between Odin3 on my W10 PC, and the tablet, in it's Download mode. I had installed an old version of Samsung Kies some years ago in support of an early cell phone, and forgot about it. Installing the latest Samsung USB driver package seemed to cause some problems with Odin, but the underlying cause was never clear. After multiple uninstalls, and re-installs of a couple of versions of the Driver, and lots of Reboots, and some analysis of my USB subsytem with the marvelous USB TreeView utility (part of the MS Driver Dev Kit, and supported and improved by Uwe Sieber), I was able to see the tablet's download connection in Odin!
The Samsung standard Download / Recovery Tool is useful and deceptively simple. So simple, in fact, that no-one really bothers to clearly and correctly describe how to invoke it, and cause it to actually begin a USB download!! After some twiddling and references to the many partial notes online about how to get the actual download to begin, wondering all the time if this was a USB driver issue, things finally came together, and the TWRP Recovery Utility (twrp2870-20150814-p4wifi.zip) began to download and install, with no further issues.
 |
| Fig 3- TWRP Running on my Galaxy Tab, Prior to Backup, and Updates. |
Everything else was easy from this point on! Be sure to use decatf's update to the AOSP 5.1.1 ROM file, from 20171009 . It worked great for me. I also installed the Google Play program set in p75xx-gapps-L-7-17-15.zip, with no problems.
I now have an updated Galaxy Tab 10.1, running well, without the problems I had before, and with some additional capabilities, such as overclocking, I have yet to explore.
The updated Android has a different look to it, wrt V4.0.4 . It is very familiar, since it tends to match the appearance of my Nexus 5 smartphone, which runs Android V6.0.1 !
 |
| Fig 4- Galaxy Running 5.1.1 - Home Screen, Post Update |
 |
| Fig 5- Galaxy About Page, Post Update. |
Saturday, 25 March 2017
3D Printing Example...
I acquired a Prusa i3 type 3D Printer kit late last year from ElectronicGeek.com (EG) (Montreal; great printer, good price compared to eBay import for same printer, and great customer service from EG, btw!) The printer works reasonably well as built; the learning curve for solving the problems that occasionally appear is not trivial, but I am making progress.
We decided to use PLA only until we have a very good reason to use something else. Although I have a heated aluminum bed that works well, it is not needed for PLA work so far. I use blue painters tape (from Home Depot) to cover the bed, and get mostly good adhesion, as long as I change the tape frequently (no more than half a dozen prints in the same place, otherwise adhesion starts to become unacceptable).
A recent print that turned out well, was a case for my recently acquired Electronic Device Tester. This device, the LCR-T3-H, is a very versatile Arduino-based tester that handles many different types of 2 and 3 terminal, active and passive components. I've included some photos of several types of components being tested. The particular device I bought is based on a public domain design that is very well documented here: https://www.mikrocontroller.net/articles/AVR_Transistortester .
This design was straightforward to print in PLA (despite a small amount of warping from insufficient bed sticking). The pcb is a tight fit, and the display panel backlight connections stick out a small amount past the edge of the pcb, requiring that a small section of the side wall of the case be cut out to allow the pcb to fit in the case. Still works very well.
 |
| Top view of case, shows startup info. |
 |
| Back view, base removed. ATMEGA386 smt chip, 8MHz crystal, not much else! |
 |
| Back of case is a tight fit, screws not really needed. Print looks good... |
 |
| Testing a Cap. One button operation, auto power off, tests battery on power up. |
 |
| Inductor test. But very small inductance looks like a Resister... |
 |
| PNP xistor. also does FETs, SCRs, Diodes, etc. SMT parts too. |
Monday, 15 August 2016
3D Printing: First Object Success!!
As much as I would like to build one of these printers, just because it's neat, we thought we should learn more about process and uses first. A couple of visits to the HPL MakerSpace convinced us to start there. So I decided to print a solar panel holder for Roz' Little Library (to charge the batteries that run it's computer, of course!). Several days of learning and working with TinkerCAD design tool produced a very nice design, so I registered with the Library, and scheduled a couple of hours last night on one of their MakerBot Replicator 3D Printers. We are very pleased with the outcome, and will certainly try more. Total print time: 1 hour 45 minutes. Total cost: $1.90 .
 |
| The TinkerCad Design image |
 |
| Printed frame with solar panel and wiring installed. |
 |
| Printing underway, on the MakerBot Replicator+ at the HPL MakerSpace. Frame is printed upside down. |
Sunday, 14 August 2016
Arduino on Battery...
I've thoroughly enjoyed learning about, and using, small Arduino microcomputers.
My collection includes Nano's (5V, 16MHz, USB, Volt Reg, 328P, china clones) and Micro Pro's (both 3.3V and 5V versions, china clones).
But it is important to find applications for them. A Little Library became an interest in our family when the grandkids discovered one in their neighbourhood, so we are soon to have one on our lawn. It seemed reasonable to add a little light to the library to make it easier to use in the evenings, so a small battery powered, solar panel charged light was obtained for this purpose. Seemed an excellent device; the lamp looks good, offers the equivalent of a 15W bulb at about 150mA, and has an 800mAh LiIon cell to run it. The included little solar panel (3 x 5 inch) was naked, but a simple 3D printed holder took care of that (another story...)
But the light needed to come on only when the little doors to the library are open, and it is probably a good idea to add a little timer to check if the doors are left open, and turn off the the light to save the battery. And we don't need to turn on the light if it is daylight outside, right? And, since we added those little door switches, we should probably keep track of how busy our Little Library is... And maybe we should report some this data, along with monitoring the battery charging and voltage, somewhere more convenient, perhaps with a radio data link.... So now we have progressed a long way from the little power switch that comes with the original light system...
Wow!! An excellent application for a little Arduino and a few other goodies!!
The interesting catch here is that the Little Library sits at the edge of the street, far away from the usual power sources. But an Arduino doesn't use much power, and the solar panel should keep that little battery charged; it says so right in the marketing literature. So we proceeded to build a little interface, to hold a Nano, and some interface circuitry to read switches and voltages, and control the light, and connect to a nice little data radio system running at 2.4GHz. We also added a couple of voltage regulators; a 5V Booster to ensure 5V to the Nano, and a 3.3V regulator to ensure good voltage to the radio. We got most everything working, then thought it might be useful to take some measurements. It's not wise to run a LiIon cell down too low, after all...
Well, the electronics I added, minus the radio, draws about 40mA, and if the sun isn't out, the solar panel only supplies about 5mA charge current!! And the lamp isn't even on yet!! More work needs to be done!
There is a lot of information available online concerning the use of the Atmel 328P low power, or Sleep modes, and a number of very good Arduino IDE Libraries exist to make it easy to use them. One confusing aspect of some of the Sleep modes seems to be how long it takes for the 328P uC to Wake Up after being in Sleep mode. Not a lot of info available, and what there is seems unclear. Suggestions range from a uS to 65mS+!!!. Since I am running some contact debounce and voltage filtering logic on a time base presently set to 5mS, It is important to know what is really happening. So I did a little testing, to determine this, and also to see what power savings were possible with my Nano, even though the USB and V Regulator chips have no sleep mode.
The test routine I used is very simple:
#include <Sleep_n0m1.h>
// Test startup delay for various sleep modes.
// Use Sleep_n0m1 to provide 15mS sleep periods, set, then reset an output bit, then loop.
// measure sleep interval with scope...
Sleep sleep;
unsigned long sleepTime; //how long you want the arduino to sleep
void setup() {
sleepTime = 15; //set sleep time in ms, max sleep time is 49.7 days
pinMode(6, OUTPUT); // pulse to monitor sleep time.
digitalWrite(6, 0); // ensure bit is off to start
}
void loop() {
/* modes of sleep
SLEEP_MODE_IDLE
SLEEP_MODE_ADC
SLEEP_MODE_PWR_SAVE
SLEEP_MODE_EXT_STANDBY
SLEEP_MODE_STANDBY
SLEEP_MODE_PWR_DOWN
*/
sleep.pwrDownMode(); //set sleep mode
sleep.sleepDelay(sleepTime); //sleep for: sleepTime (use delay(15) instead when not sleeping)
// sleep ends here. Pulse output bit quickly (about 4uS)
digitalWrite(6, 1);
digitalWrite(6, 0);
}
With this and my scope (Hantek 6022BE DSO), and a meter to measure current draw to the Nano, I got some very interesting results, which might be of use to others:
Sleep Mode: Loop Time: mA @ 5V: mA @ 4.2V
None [use Delay(19)] 19.0mS 21.6 13.5
Idle 19.0mS 13.7 8.4
Standby 18.9mS 7.0 5.4
Power Down 19.9mS 6.6 5.1
Notes:
- Loop time differences of 18.9 vs 19.0 prob. due to accuracy of cursor readings on my DSO
- Power Down mode saves a bit more power, but adds 1.0mS to wake up times
- supply V = 4.2V was also tested, to estimate savings on direct LiIon cell voltage
- Loop time was unchanged when supply V changed.
- using a nominal sleep duration of 15mS on this particular Nano results in almost 19mS of actual sleep time. Since my reading suggests that other sleep mode wake up times, due to hardware, are very very small, this must be due to a substantially different WDT oscillator frequency, which was not affected by supply V.
- the data above suggests that the 328P in the Nano is configured for a "Full Swing Crystal Oscillator Clock", which prevents the CPU from running for 16K clock cycles after startup of the oscillator. At 16MHz, this will be about 1mS, the added amount in the Power Down sleep mode.
- the no sleep mode case used a Delay function, set to match the sleep loop times, instead of a Sleep function.
A Mini Pro, running at 3.3V would allow additional savings, prob. under 1mA average consumption. However, since my Library electronics includes a socket for a Nano, and the Mini Pro pinout is substantially different from a Nano, I will operate with the Nano, at 4.2V for a while. If an additional power savings is needed, I can rewire the electronics to accept a Mini Pro. I can also remove the 5V Booster (uses about 3mA idling, not included in these measurements ), and look at shutting off the 3.3V Regulator (another 3mA idling), if needed.
Hopefully real world edge of road install tests will show much higher solar panel charge currents on average, and worst case, sufficient to provide enough charge during the day to run the electronics for a 24 hr period...
Now back to my code rewrites, since the millisecond function, and the Bounce2 and SimpleTimer Libraries that depend on it, will no longer work in the Low Power Sleep World...
My collection includes Nano's (5V, 16MHz, USB, Volt Reg, 328P, china clones) and Micro Pro's (both 3.3V and 5V versions, china clones).
But it is important to find applications for them. A Little Library became an interest in our family when the grandkids discovered one in their neighbourhood, so we are soon to have one on our lawn. It seemed reasonable to add a little light to the library to make it easier to use in the evenings, so a small battery powered, solar panel charged light was obtained for this purpose. Seemed an excellent device; the lamp looks good, offers the equivalent of a 15W bulb at about 150mA, and has an 800mAh LiIon cell to run it. The included little solar panel (3 x 5 inch) was naked, but a simple 3D printed holder took care of that (another story...)
But the light needed to come on only when the little doors to the library are open, and it is probably a good idea to add a little timer to check if the doors are left open, and turn off the the light to save the battery. And we don't need to turn on the light if it is daylight outside, right? And, since we added those little door switches, we should probably keep track of how busy our Little Library is... And maybe we should report some this data, along with monitoring the battery charging and voltage, somewhere more convenient, perhaps with a radio data link.... So now we have progressed a long way from the little power switch that comes with the original light system...
Wow!! An excellent application for a little Arduino and a few other goodies!!
The interesting catch here is that the Little Library sits at the edge of the street, far away from the usual power sources. But an Arduino doesn't use much power, and the solar panel should keep that little battery charged; it says so right in the marketing literature. So we proceeded to build a little interface, to hold a Nano, and some interface circuitry to read switches and voltages, and control the light, and connect to a nice little data radio system running at 2.4GHz. We also added a couple of voltage regulators; a 5V Booster to ensure 5V to the Nano, and a 3.3V regulator to ensure good voltage to the radio. We got most everything working, then thought it might be useful to take some measurements. It's not wise to run a LiIon cell down too low, after all...
Well, the electronics I added, minus the radio, draws about 40mA, and if the sun isn't out, the solar panel only supplies about 5mA charge current!! And the lamp isn't even on yet!! More work needs to be done!
There is a lot of information available online concerning the use of the Atmel 328P low power, or Sleep modes, and a number of very good Arduino IDE Libraries exist to make it easy to use them. One confusing aspect of some of the Sleep modes seems to be how long it takes for the 328P uC to Wake Up after being in Sleep mode. Not a lot of info available, and what there is seems unclear. Suggestions range from a uS to 65mS+!!!. Since I am running some contact debounce and voltage filtering logic on a time base presently set to 5mS, It is important to know what is really happening. So I did a little testing, to determine this, and also to see what power savings were possible with my Nano, even though the USB and V Regulator chips have no sleep mode.
The test routine I used is very simple:
#include <Sleep_n0m1.h>
// Test startup delay for various sleep modes.
// Use Sleep_n0m1 to provide 15mS sleep periods, set, then reset an output bit, then loop.
// measure sleep interval with scope...
Sleep sleep;
unsigned long sleepTime; //how long you want the arduino to sleep
void setup() {
sleepTime = 15; //set sleep time in ms, max sleep time is 49.7 days
pinMode(6, OUTPUT); // pulse to monitor sleep time.
digitalWrite(6, 0); // ensure bit is off to start
}
void loop() {
/* modes of sleep
SLEEP_MODE_IDLE
SLEEP_MODE_ADC
SLEEP_MODE_PWR_SAVE
SLEEP_MODE_EXT_STANDBY
SLEEP_MODE_STANDBY
SLEEP_MODE_PWR_DOWN
*/
sleep.pwrDownMode(); //set sleep mode
sleep.sleepDelay(sleepTime); //sleep for: sleepTime (use delay(15) instead when not sleeping)
// sleep ends here. Pulse output bit quickly (about 4uS)
digitalWrite(6, 1);
digitalWrite(6, 0);
}
With this and my scope (Hantek 6022BE DSO), and a meter to measure current draw to the Nano, I got some very interesting results, which might be of use to others:
Sleep Mode: Loop Time: mA @ 5V: mA @ 4.2V
None [use Delay(19)] 19.0mS 21.6 13.5
Idle 19.0mS 13.7 8.4
Standby 18.9mS 7.0 5.4
Power Down 19.9mS 6.6 5.1
Notes:
- Loop time differences of 18.9 vs 19.0 prob. due to accuracy of cursor readings on my DSO
- Power Down mode saves a bit more power, but adds 1.0mS to wake up times
- supply V = 4.2V was also tested, to estimate savings on direct LiIon cell voltage
- Loop time was unchanged when supply V changed.
- using a nominal sleep duration of 15mS on this particular Nano results in almost 19mS of actual sleep time. Since my reading suggests that other sleep mode wake up times, due to hardware, are very very small, this must be due to a substantially different WDT oscillator frequency, which was not affected by supply V.
- the data above suggests that the 328P in the Nano is configured for a "Full Swing Crystal Oscillator Clock", which prevents the CPU from running for 16K clock cycles after startup of the oscillator. At 16MHz, this will be about 1mS, the added amount in the Power Down sleep mode.
- the no sleep mode case used a Delay function, set to match the sleep loop times, instead of a Sleep function.
A Mini Pro, running at 3.3V would allow additional savings, prob. under 1mA average consumption. However, since my Library electronics includes a socket for a Nano, and the Mini Pro pinout is substantially different from a Nano, I will operate with the Nano, at 4.2V for a while. If an additional power savings is needed, I can rewire the electronics to accept a Mini Pro. I can also remove the 5V Booster (uses about 3mA idling, not included in these measurements ), and look at shutting off the 3.3V Regulator (another 3mA idling), if needed.
Hopefully real world edge of road install tests will show much higher solar panel charge currents on average, and worst case, sufficient to provide enough charge during the day to run the electronics for a 24 hr period...
Now back to my code rewrites, since the millisecond function, and the Bounce2 and SimpleTimer Libraries that depend on it, will no longer work in the Low Power Sleep World...
Saturday, 13 August 2016
MS Mail confusion...
Email is an important part of our ability to communicate, stay in touch, do business, and more. So it would seem that MS would provide stable, functional email clients for it's Windows OS, no? Although I am comfortable with Linux and Android variants (among others), my everyday desktop PC is Windows based. I am a fan of client email apps, partly to allow me some control over storage and back-up of enduring email threads. Maybe it's my IT background, but I don't have complete confidence in "the cloud" to look after the security and privacy of everything.
In the beginning of my GUI-based email experience, there was Outlook Express. A reasonable email client, and worked in a similar manner to the work-based full Outlook. It ran for a long time, but then there was warnings of EOL, and occasional problems, and new problems, and many encouragements from MS to switch. The client du jour was Windows Live Mail. After some checking and testing, I switched. Eventually, it worked in an acceptable manner, although not without lots of issues along the way. But it had been stable for several years, and we had learned to get along.
Wash rinse, repeat... Troubles started to appear with Live email. Lost emails, synch problems, strange freezes, the need to restart the app, or the OS... The warnings about EOL started to appear. The switch to WIN10 didn't help. The many encouragements from MS to switch again began, this time to Windows Mail, included with WIN10. I resisted the approach for a while, but finally decided anything would be better than the Live Email problems. So after doing some due diligence on this new Mail program, I switched....
Initially, it looked like just another learning curve. What was wrong with the last mail user interface, that MS decided I had to experience a completely different one, not intuitive at all? And, btw, what happened to that local storage method I liked so much? Seems the only easy solution (??) was to move all those local nicely categorized emails back out to an email server!!
So I gradually got used to doing things the 'new' way, and we developed a moderately comfortable existence.
Then I discovered "Auto Capitalization"!!! (something sent as all lower case, that needed to be used that way, got Capitalized!) wtf? I didn't ask for this, no other email client ever did this, and, afaik, there is no way to turn it off!! (the suggestions in various blogs don't work, and a LOT of people are asking how....)
MS, you need to step up your act a bit here...
In the beginning of my GUI-based email experience, there was Outlook Express. A reasonable email client, and worked in a similar manner to the work-based full Outlook. It ran for a long time, but then there was warnings of EOL, and occasional problems, and new problems, and many encouragements from MS to switch. The client du jour was Windows Live Mail. After some checking and testing, I switched. Eventually, it worked in an acceptable manner, although not without lots of issues along the way. But it had been stable for several years, and we had learned to get along.
Wash rinse, repeat... Troubles started to appear with Live email. Lost emails, synch problems, strange freezes, the need to restart the app, or the OS... The warnings about EOL started to appear. The switch to WIN10 didn't help. The many encouragements from MS to switch again began, this time to Windows Mail, included with WIN10. I resisted the approach for a while, but finally decided anything would be better than the Live Email problems. So after doing some due diligence on this new Mail program, I switched....
Initially, it looked like just another learning curve. What was wrong with the last mail user interface, that MS decided I had to experience a completely different one, not intuitive at all? And, btw, what happened to that local storage method I liked so much? Seems the only easy solution (??) was to move all those local nicely categorized emails back out to an email server!!
So I gradually got used to doing things the 'new' way, and we developed a moderately comfortable existence.
Then I discovered "Auto Capitalization"!!! (something sent as all lower case, that needed to be used that way, got Capitalized!) wtf? I didn't ask for this, no other email client ever did this, and, afaik, there is no way to turn it off!! (the suggestions in various blogs don't work, and a LOT of people are asking how....)
MS, you need to step up your act a bit here...
Subscribe to:
Posts (Atom)