Go to advanced search

by mosespi
Mon Mar 12, 2018 2:14 am
Forum: General discussion
Topic: UPS solutions?
Replies: 21
Views: 2866

Re: UPS solutions?

I have a (primarily) NiMH battery based UPS specifically designed for the Pi: http://www.allspectrum.com/mopower/ I don't really understand your discharge/recharge/deterioration question. Most all batteries deteriorate over time, and have limited cycle and shelf life. Standard lead, lithium and nick...
by mosespi
Sun Jul 23, 2017 5:21 am
Forum: Automation, sensing and robotics
Topic: Can't Recharge While RPi Is On
Replies: 8
Views: 1386

Re: Can't Recharge While RPi Is On

MoPower UPS I needed to study this puppy a bit. It looks good as a UPS, but 50ma charge rate won't get me 4000ma over night. Oh well, was hoping. You can change the charge current resistor within certain power dissipation and other limits. The default 52ma was selected as a slow trickle charge that...
by mosespi
Fri Jul 21, 2017 11:13 pm
Forum: Automation, sensing and robotics
Topic: Can't Recharge While RPi Is On
Replies: 8
Views: 1386

Re: Can't Recharge While RPi Is On

You have a 7.2v input, so I'm assuming you have a DC-DC converter. If that is the case, with the addition of a diode you can isolate the battery using another power source. In between your battery and DC-DC converter add a diode, and before hooking up your charger connect a 12v+ source (assuming you...
by mosespi
Fri Jul 21, 2017 7:43 am
Forum: General discussion
Topic: [Ask] Wiring Amplifier into UPS Hat Board?
Replies: 6
Views: 1070

Re: [Ask] Wiring Amplifier into UPS Hat Board?

I make a competing UPS.. so take this as you will.. but I don't think that UPS is complete. Some have reported issues with battery charging and there is a general lack of information on the board. See this forum topic: https://www.raspberrypi.org/forums/viewtopic.php?f=45&t=174392 Not a problem on y...
by mosespi
Fri Jul 21, 2017 7:22 am
Forum: Other projects
Topic: arduino nano as smart power controller for pi zero
Replies: 5
Views: 2234

Re: arduino nano as smart power controller for pi zero

Yes, you describe the basic building blocks of my UPS. See here: http://www.allspectrum.com/mopower/ There is a schematic towards the end of the PDF user manual you can take a look at. It uses a low power microcontroller from Atmel, similar to the Arduino, which acts as a power supervisor for the Pi...
by mosespi
Wed Jul 19, 2017 7:57 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: How to test if UART works ?
Replies: 1
Views: 1292

Re: How to test if UART works ?

Is there a way to check if Pis UART pins are still alive ? For example hooking pin 8(TX) to pin 10(RX) and using something like minicom to send and receive ? Yes, that is exactly what you do. Short the pins together and anything you send out should come back. If the pins are dead is there a way to ...
by mosespi
Wed Jul 19, 2017 7:47 pm
Forum: General discussion
Topic: Powering exteranl 3.3V device
Replies: 5
Views: 2136

Re: Powering exteranl 3.3V device

Julyjim, The schematic of the Pi 3 lists a PAM2306AYPKE as the regulator for the 3.3v and 1.8v rail. If designed to spec.. the datasheet for the device lists a max output of 1A per rail. Although there are other variables to consider as well, the information so far tells me that pulling 30ma or so f...
by mosespi
Wed Jul 12, 2017 8:06 am
Forum: Beginners
Topic: Can I connect the battery to the Raspberry Pi?
Replies: 10
Views: 1586

Re: Can I connect the battery to the Raspberry Pi?

No , the battery monitor applet does not work on any real , fresh from the factory Raspberry Pi. I know of one (1) third-party UPS add-on which actually works with that applet. ghans Mopower, at a guess? This on the grounds that if anyone has managed to implement the feature, I'd be inclined to thi...
by mosespi
Tue Jul 11, 2017 7:26 am
Forum: General discussion
Topic: Unpleasant new board smell ?
Replies: 68
Views: 10468

Re: Unpleasant new board smell ?

Did the Raspberry-pi police change my topic title? I asked for it to be changed because no-one has died or even been slightly harmed (so far) Even myself, quite known for biting at the hand that feeds us, thought it was a bit much :) I say we change it to "pleasant new board smell ?" because I sort...
by mosespi
Tue Jul 11, 2017 5:41 am
Forum: Troubleshooting
Topic: Ultimate GPS - Need Help With NTP
Replies: 2
Views: 862

Re: Ultimate GPS - Need Help With NTP

Hi Jim, Did you hook up the PPS output of the GPS to the Pi? The PPS output gives the receiving computer (NTP) a more accurate indication of exactly what time it is. When using just plain old UART/SPI without PPS output there is jitter introduced. Basically the time data send by the GPS doesn't alwa...
by mosespi
Mon Jul 10, 2017 8:11 pm
Forum: General discussion
Topic: Raspberry Pi power cut torture test using a MoPower UPS
Replies: 30
Views: 5988

Re: Raspberry Pi power cut torture test using a MoPower UPS

Has anyone seen anything official on any modifications made to the Pi for SD card reliability.. firmware, hardware, software, anything? Maybe in some release notes or any postings? My vague recollection is that diminishing reports of SD card corruption coincided somewhat with changes to Raspbian or...
by mosespi
Wed Jun 28, 2017 7:32 pm
Forum: General discussion
Topic: Raspberry Pi power cut torture test using a MoPower UPS
Replies: 30
Views: 5988

Re: Raspberry Pi power cut torture test using a MoPower UPS

I found an old Model B Pi and restarted the test. Using the same software that was on the SD card already from the prior test. This is a non-brownout setup without extra capacitors but with the heavy write test. Boot count was 5,803 when I stopped the test! System is normal. I'm looking at possibly...
by mosespi
Sat Jun 24, 2017 5:58 am
Forum: Networking and servers
Topic: Running multiple pi's on a tractor
Replies: 26
Views: 4956

Re: Running multiple pi's on a tractor

Octradox, Yes, a DC-DC converter is what is needed here. Some numbers for you.. - A Pi 3 with camera recording and all CPU cores going full bore will take about 1.0 amp or so, say 1.2 amp to be safe. I am assuming you don't have any other large power draws on the Pi, high draw USB devices for exampl...
by mosespi
Fri Jun 23, 2017 7:00 pm
Forum: General discussion
Topic: Raspberry Pi power cut torture test using a MoPower UPS
Replies: 30
Views: 5988

Re: Raspberry Pi power cut torture test using a MoPower UPS

Hello Everyone! I found an old Model B Pi and restarted the test. Using the same software that was on the SD card already from the prior test. This is a non-brownout setup without extra capacitors but with the heavy write test. Has anyone seen anything official on any modifications made to the Pi fo...
by mosespi
Fri Jun 23, 2017 1:08 am
Forum: General discussion
Topic: DHT22 PI3 intermittent bad data
Replies: 16
Views: 2783

Re: DHT22 PI3 intermittent bad data

I don't believe you can read values from a DTH22 very quickly. Put a few seconds of delay between each read. Search online, you will see others usually do the same as well. You might have been introducing a delay without knowing it prior.. or the specific sensor you have was reacting quicker.. or te...
by mosespi
Thu Jun 22, 2017 9:12 pm
Forum: General discussion
Topic: Raspberry Pi power cut torture test using a MoPower UPS
Replies: 30
Views: 5988

Re: Raspberry Pi power cut torture test using a MoPower UPS

I stopped the latest test. This test was a brownout with heavy SD card writing. No problems. Final boot count was 5,012!!!

The system works normally and the SD card did not go read only as the boot logs are complete.

Time to dig out some older Pi models and retest!

Regards,
-Moses
by mosespi
Thu Jun 22, 2017 6:45 am
Forum: Other projects
Topic: Measuring (Low) Power Usage Over Time
Replies: 15
Views: 2407

Re: Measuring (Low) Power Usage Over Time

These INA219 modules work pretty well for me. http://www.allspectrum.com/store/ina219-i2c-bi-directional-current-power-monitor-sensor-module-p-9161.html You will need to splice your input power, but that is not difficult. I've used them hooked directly to the Pi with good results. Good accuracy too ...
by mosespi
Fri Jun 16, 2017 7:23 am
Forum: General discussion
Topic: Raspberry Pi power cut torture test using a MoPower UPS
Replies: 30
Views: 5988

Re: Raspberry Pi power cut torture test using a MoPower UPS

Ok, but before starting the copy, could you update a file with a sequence number and include that in the request to the webserver? Then you could check the webserver logs for myrequest&seq=.... and make sure that the sequence number updates. Otherwise you could be booting on a useless read-only car...
by mosespi
Fri Jun 16, 2017 7:01 am
Forum: General discussion
Topic: Raspberry Pi power cut torture test using a MoPower UPS
Replies: 30
Views: 5988

Re: Raspberry Pi power cut torture test using a MoPower UPS

It might be interesting to try this test with different models/makes of SD card to see which can handle the repeated power failure scenario best. Also, did you check on each reboot that the files written on the previous one were maintained? SD cards do have a failure mode where things appear to be ...
by mosespi
Fri Jun 16, 2017 6:36 am
Forum: General discussion
Topic: Raspberry Pi power cut torture test using a MoPower UPS
Replies: 30
Views: 5988

Re: Raspberry Pi power cut torture test using a MoPower UPS

An update: I stopped the slow brownout test at 4,464 startups. It occasionally failed to boot, getting stuck on the large rainbow square (note this is not the small rainbow square error). The failed boot ups became more frequent until they got troublesome and I elected to end the test. This was not ...
by mosespi
Thu Jun 15, 2017 6:23 pm
Forum: Beginners
Topic: auto bootdown when gpio 5v gets 0v
Replies: 5
Views: 961

Re: auto bootdown when gpio 5v gets 0v

exacyl what i should need, but for me its quite a hassle to order from a out of europe far away land.. i live in the netherlands. so price wise its quite expensive i gues... are there any alternatives on ebay/ ali express maybe? (i know its your own chip and i understand you dont want to support ot...
by mosespi
Sat Jun 10, 2017 6:51 pm
Forum: Beginners
Topic: auto bootdown when gpio 5v gets 0v
Replies: 5
Views: 961

Re: auto bootdown when gpio 5v gets 0v

You can use my UPS in a car PC: http://www.allspectrum.com/mopower/ 12-20v input, TVS for voltage spikes and can detect when the car (a regular alternator) is on without a switched ignition input. I have a Pi in the car as well and I like to power them with constant power using my UPS. I normally do...
by mosespi
Sun Jun 04, 2017 10:26 pm
Forum: General discussion
Topic: Raspberry Pi power cut torture test using a MoPower UPS
Replies: 30
Views: 5988

Re: Raspberry Pi power cut torture test using a MoPower UPS

I attached a 1.5F supercapacitor (two 3F in series actually) Umm. Assuming an adequate voltage rating, then to add the capacitance the supercaps should be in parallel. :o The effective value of caps in series follows the same formula as resistors in parallel. But the overall voltage rating is the s...
by mosespi
Sat Jun 03, 2017 8:37 pm
Forum: General discussion
Topic: Raspberry Pi power cut torture test using a MoPower UPS
Replies: 30
Views: 5988

Re: Raspberry Pi power cut torture test using a MoPower UPS

I finally decided to end the "write while power cut" test.. final successful boot count is 27,327!!! The system was working normally when I stopped the test! For the next round of testing I attached a 1.5F supercapacitor (two 3F in series actually) on the 5v lines, which gives a gradual voltage drop...
by mosespi
Wed May 31, 2017 7:53 am
Forum: General discussion
Topic: Setting up a Pi 3 for the long haul?
Replies: 44
Views: 7321

Re: Setting up a Pi 3 for the long haul?

3. I have a question about the MoPower UPS, and perhaps there is a better place than here to ask it? Anyway, this may already be on the MoPower web page but it's not clear to me: In order to give the flash drive (SD or USB) sufficient time to perform shutdown procedures, can (or is) the MoPower be ...

Go to advanced search